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No, NK cells are not CD3 positive. NK cells do not express the CD3 marker, which is typically found on T cells.

1 answer


The CD3 lets you play 2 songs on your stereo: Fur Elise and another song I don't know the name to. Just select the CD3 and select the track you want. it WILL NOT break your stereo!

1 answer


The chemical formula for cadmium phosphate is Cd3(PO4)2.

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CD3 cells are a type of T lymphocyte that play a crucial role in the immune response by recognizing and attacking foreign invaders like viruses and bacteria. These cells express the CD3 receptor on their surface, which helps them recognize antigens presented by other cells in the immune response. CD3 cells also help regulate the immune response and maintain immune tolerance.

2 answers


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Navy rating CD3 was a Seabee designation for

Construction Driver, Petty Officer Third Class

1 answer


A CD3+ ion has 3 electrons. The "3" in CD3 refers to the number of carbon-hydrogen bonds in the group. Since carbon typically forms 4 bonds, one of those bonds is to the ion that carries a positive charge, resulting in a total of 3 electrons.

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Full form of CD is cluster of designation or cluster of differentiation.

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The chemical formula for cadmium arsenate is Cd3(AsO4)2. It is a compound formed by combining cadmium (Cd) and arsenate (AsO4) ions. Cadmium arsenate is a toxic substance that is used in the production of pigments and insecticides.

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Class I MHC molecules present antigens to cytotoxic T-cells (which are CD3+CD8+).

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when erythrocytes bind to CD3 receptors present on the surface of T-cell it will give rose like appearance to T-cell this process is called as T-cell rosetting

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1. Media Max CD3 was put on 50 disc, XCP was put on 52 disc
Mediamax CD-3 and Extended Copy Protection

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CD183 and CD 184 are 2 chemokine receptors and their expression on T cells is normal.

But expressed on tumor cells, they are associated with metastasis.

I hope this helped,

Feanor

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Here are codes for versions 2, 3, 4, 4.5, and, 5

Version 2:

ABBA CBCC = Whole Cake (worth 600p)

BACB CACB = Steak (worth 800p)

BCBA CABA = Love Potion/Honey (worth 3000p)

CBAA CABC = Stuffed Animal = Panda Costume (worth 2500p)

ACBC ABAC = Hair Gel (worth 400p)

Version 3:

CBAC CABC = cuckoo clock (worth 4000p)

AABB CACB = RC Car2 (worth 2800p)

CACA BABC = stuffed animal = Nyatchi costume (worth 2500p)

BCBC CABA = love potion/honey (worth 2000p)

BCAB ACBC = steak (worth 800p)

ABBA ACBA = cake (worth 600p)

ACBB BACC = hair gel (worth 400p)

Here are V3 Passwords too:

32479 91490 - !! clone

63532 86367 - pen

Version 4

BBCA CCCA= Pen= 15,000gp

ACAB ACAC= Steak= 1,400gp

BAAB ACBA= !! (clone)= 14,000gp

CCBA AABB= Honey (love potion)= 7,000gp

CAAA BACB= CD3= 0gp

V4 Passwords too:

40690 89391= Playhouse

52815 99088= Slide

Version 4.5

BCAA CBAB= Pen= 15,000gp

BABC BAAA= Steak= 1,400gp

CAAC BBCB= !! (clone)= 14,000gp

BBAA ABCB= Honey (love potion)= 7,000gp

CCCA CBBC= CD3= 0gp

Passwords:

See version 4

So there you go enjoy!!!

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pen-bbca ccca steak-acab acac !!(clone)-baab acba honey-ccba aabb cd3-caaa bacb playhouse-40690 89391 slide-52815 99088

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The Mazda CX-9 is based on the Ford CD3 platform which is shared with the Ford Edge and Lincoln MKX. It is a modified version of the 1st generation (2003-2008) Mazda6, which was also the basis for the 2006-2012 Ford Fusion, Mercury Milan and Lincoln MKZ.

1 answer


There is no equation that we can see.

Unfortunately, limitations of the browser used by Answers.com means that we cannot see most symbols. It is therefore impossible to give a proper answer to your question. Please resubmit your question spelling out the symbols as "plus", "minus", "equals" etc. And using ^ to indicate powers (eg x-squared = x^2).

1 answer


All of the V4.5 shop codes please note, codes are in the following order; Code=what it gives you=points needed to buy after first time entering in GP ((gp=gotchi points))

1. BCAA CBAB= Pen= 15,000gp

2. BABC BAAA= Steak= 1,400gp

3. CAAC BBCB= !! (clone= 14,000gp

4. BBAA ABCB= Honey (love potion= 7,000gp

5. CCCA CBBC= CD3= 0gp

~If you enter all five shop codes, the last code you enter will not give you what the code is for! Instead, it will give you a RARE CELL PHONE. If you would still like to get the last item from the last code, you will have to enter the code again the code and buy it. I recommend entering the code for "CD3" last because it is free!

2 answers


Depends on your user name but if you want the shop codes:

1. BBCA CCCA= Pen= 15,000gp (found in US V4 instruction sheet)

2. ACAB ACAC= Steak= 1,400gp

3. BAAB ACBA= !! (clone)= 14,000gp

4. CCBA AABB= Honey (love potion)= 7,000gp

5. CAAA BACB= CD3= 0gp

ALL CREDIT GOES TO: tamatalk.com

--mewMew

1 answer


Heres the V4:

1. BBCA CCCA= Pen= 15,000gp (found in US V4 instruction sheet)

2. ACAB ACAC= Steak= 1,400gp

3. BAAB ACBA= !! (clone)= 14,000gp

4. CCBA AABB= Honey (love potion)= 7,000gp

5. CAAA BACB= CD3= 0gp

ALL CREDIT GOES TO tamatalk.com

If you mean something else, comment on my message board and I'll get back to you ASAP.

--MewMew

1 answer


V4 tanagotchi codes: Pen = 15,000 gp:

BBCA CCCA.

Steak = 1,400 gp:

ACAB ACAC.

Clone = 14,000 gp:

BAAB ACBA.

Honey = 7,000 gp:

CCBA AABB.

CD3 = 0 gp:

CAAA BACB.

The last code you enter will not give you what the code is for! Instead, it will give you a RARE CELL PHONE. If you would still like to get the last item from the last code, you will have to re-enter the code and buy it. I recommend entering the code for "CD3" last because it is free!

1 answer


Ba+2 C2H3O2-1 <---- these are the ions and their charges

Ba+2 C2H3O2-1 C2H3O2-1 <---- the charges have to add up to zero, so one +2 barium ion cancels out two -1 acetate ions

Ba(C2H3O2)2<---- simplify

7 answers


Maria Luisa Altieri Biagi has written:

'Didattica dell'italiano' -- subject(s): Study and teaching, Italian language

3 answers


The overall charge of the compound Cd3(PO4)2 is neutral. Since the phosphate ion (PO4) has a charge of -3, we can determine that each cadmium ion (Cd) has a charge of +2 in order to balance the charges and achieve a neutral ionic compound.

7 answers


Chlorella has been shown to reduce the side effects of radiation therapy. Early research suggests chlorella tablets plus chlorella liquid extract might help people with a type of brain cancer called glioma better tolerate chemotherapy and radiation treatments, possibly by boosting the immune system. Unfortunately, chlorella doesn't seem to slow the progression of the cancer or improve survival.

Some people also use chlorella for the prevention of stress-related ulcers; treatment of constipation, bad breath, and hypertension; as an antioxidant; to reducecholesterol; to increase energy; to detoxify the body; and as a source of magnesium to promote mental health, relieve premenstrual syndrome (PMS), and reduce asthma attacks. It is also used for fibromyalgia.

NOTE:

  • Medications that decrease the immune system (Immunosuppressants) interacts with CHLORELLA

    Chlorella might increase the immune system. By increasing the immune system, chlorella might decrease the effectiveness of medications that are used to decrease the immune system.

    Some medications that decrease the immune system include azathioprine (Imuran), basiliximab (Simulect), cyclosporine (Neoral, Sandimmune), daclizumab (Zenapax), muromonab-CD3 (OKT3, Orthoclone OKT3), mycophenolate (CellCept), tacrolimus (FK506, Prograf), sirolimus (Rapamune), prednisone (Deltasone, Orasone), corticosteroids (glucocorticoids), and others.

  • Warfarin (Coumadin) interacts with CHLORELLA

    Chlorella contains large amounts of vitamin K. Vitamin K is used by the body to help blood clot. Warfarin (Coumadin) is used to slow blood clotting. By helping the blood clot, chlorella might decrease the effectiveness of warfarin (Coumadin). Be sure to have your blood checked regularly. The dose of your warfarin (Coumadin) might need to be changed.

1 answer


1st enter BCAA CBAB 2nd enter BBAA ABCB 3rd enter BABC BAAA 4th enter CAAC BAAA

and finally to get the rare cell phone, but you have to put all these codes in first in order to get the rare cell phone, finally type in CCCA CBBC.

9 answers


Many cash registers and POS systems come with removable cash drawers, allowing for easy cash handling and security. Here are some top options:

  1. Traditional Cash Registers with Removable Drawers

✅ Sharp XE-A207 – Popular for small businesses, with a lockable, removable drawer.

✅ Casio SE-S700 – Features a removable 4-bill, 5-coin cash drawer.

✅ Sam4s ER-180U – Compact and affordable, with a secure cash drawer.

  1. POS Cash Drawers (Used with POS Systems & Tablets)

✅ APG Vasario Series – Durable and widely used with POS systems.

✅ Star Micronics CD3-1616 – Heavy-duty metal drawer with multiple compartments.

✅ Epson Cash Drawer (Under-counter model) – Space-saving and secure.

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(please note, codes are in the following order; Code=what it gives you=points needed to buy after first time entering in gp (gp=gotchi points))

1. BCAA CBAB= Pen= 15,000gp

2. BABC BAAA= Steak= 1,400gp

3. CAAC BBCB= !! (clone)= 14,000gp

4. BBAA ABCB= Honey (love potion)= 7,000gp

5. CCCA CBBC= cell phone= 0gp

~If you enter all five shop codes, the last code you enter will not give you what the code is for! Instead, it will give you a RARE CELL PHONE. If you would still like to get the last item from the last code, you will have to re-enter the code and buy it. I recommend entering the code for "CD3" last because it is free!

How to enter shop codes? Quoting from the V4.5 instruction sheet:

Did you find a secret code?

At the shop counter screen, press (A).

Then, press (A) quickly three times. When

the shop owner's face appears surprised, punch in

the secret code to reveal a new item.

[Note: A = left button, B = middle button, C = right button]

5 answers


1. BCAA CBAB= Pen= 15,000gp

2. BABC BAAA= Steak= 1,400gp

3. CAAC BBCB= !! (clone)= 14,000gp

4. BBAA ABCB= Honey (love potion)= 7,000gp

5. CCCA CBBC= cell phone= 0gp

~If you enter all five shop codes, the last code you enter will not give you what the code is for! Instead, it will give you a RARE CELL PHONE. If you would still like to get the last item from the last code, you will have to re-enter the code and buy it. I recommend entering the code for "CD3" last because it is free!


How to enter shop codes? Quoting from the V4.5 instruction sheet:

Did you find a secret code?
At the shop counter screen, press (A).
Then, press (A) quickly three times. When
the shop owner's face appears surprised, punch in
the secret code to reveal a new item.

[Note: A = left button, B = middle button, C = right button]

--mewMew -- hope i helped (im an expert!)

1 answer


To get a clone for a Tamagotchi, you need to connect your Tamagotchi device with another Tamagotchi device that has the clone feature and complete the cloning process. This typically involves selecting the option to clone and waiting for the process to finish. Make sure both devices are compatible for cloning.

2 answers


I think the dr gives you alittle bit of clomid and then they give you the pergonal and its suposes to make you more fertile but once you take the pills and they check your estrogen level and you have more than 1 egg the most drs will ait cause they dont like the fact of a muti births like twins etc....But yes you can take thoses together. Go to google and ask which is better pergonal or clomid?......and you will see a page for this!!! Hope i was some help!....and good luck!!!!

2 answers


Did you find a secret code? At the shop counter screen, press (A). Then, press (A) quickly three times. When the shop owner's face appears surprised, punch in the secret code to reveal a new item. • 1.BBCA CCCA= Pen= 15,000gp • 2. ACAB ACAC= Steak= 1,400gp • 3. BAAB ACBA= !! (clone)= 14,000gp • 4. CCBA AABB= Honey (love potion)= 7,000gp • 5. CAAA BACB= CD3= 0gp x2 Cell phone #'s=Mr. Turtle-ACCBCAAB Parent-AABACCBB –Grandparent-CCACBCBA • Enter these codes under the bat and ball in Passwords • Slide-52815 99088 • Playhouse-40690 89391 I hope these helped.

9 answers


There are many factors that come into play when fishing rapalas for trout. In general it's a match the hatch thing with size , color and depth being the key. Usually dark colors in the early morning with sinking or countdown lures working best. If the weather is cold or if the water is 45F or below use countdowns (CD3, CD5, CD7) in natural bait colors preferably with red or orange bellies. As the sun rises look for rising fish. This can indicate that it is time for using the floating lures. I prefer orange over yellow or perch pattern floating rapalas (F3, F5, F7, F9). If you are trolling, speed is also a factor. Remenber that the faster the boat moves, the deeper your lure presentation will be. Start with a very slow troll and vary your path fishing an area in wide "s" patterns. Larger, more aggressive fish will tend to bite a faster moving lure. Also when trolling, monitor the amount of line you let out. Start with 100 feet and if necessary not more than 200 feet. The more line you let out the closer together your rapalas will ride in the pattern and the greater chance of creating a very special rapala tangle. If casting for trout find and area where the fish are working. Cast beyond the fish and "rip" the lure in several quick jerks while varying the speed of your retrieve.

So the best colors?...... For countdowns: Green over red or orange, perch, sometimes pink or rootbeer. For floaters, orange over yellow, perch, chartruse, or chrome.

3 answers


It is usually OK to get a flu vaccine when using antibiotics; there is no drug interaction problem.

However, if you are taking antibiotics, then you must have a bacterial infection. If your infection is still acute - and you have ongoing symptoms such as a high fever - you may want to consult your health-care professional to be sure that your body will be able to tolerate the immune response needed to create immunity to the virus while you are also fighting an infection by a different type of organism.

Before receiving the injection the person about to give you the vaccine will ask you a series of questions that will include questions about fever or other infection symptoms, ask this clinician if there is any reason you should not have the injection, given your current condition.

It may depend on why you are taking the antibiotics. If you have a current infection, it is usually better to wait until that is cleared up before taking vaccines. But each situation can be different and this is a question that the doctor who prescribed the antibiotics should be asked to know what is right in your case.

10 answers


Texas cast its 38 electoral votes for Donald Trump in the 2016 election. The 2016 presidential electors from Texas pledged to vote for Donald Trump for President and Mike Pence for Vice President were Candace Noble, At Large; Fred Farias, At Large; Marty Rhymes, CD1; Thomas Moon, CD2; Carol Sewell, CD3; John E. Harper, CD4; Sherrill Lenz, CD5; Nicholas Ciggelakis, CD6; Will Hickman, CD7; Landon Estay, CD8; Rex Lamb, CD9; Rosemary Edwards, CD10; Matt Stringer, CD11; Debra Coffey, CD12 (replaced Shellie Surles, ruled ineligible); Benona Love, CD13 (replaced Melissa Kalka, ruled ineligible); Sherry Clark, CD14 (replaced Kenneth Clark, ruled ineligible); Sandra Cararas, CD15; David Thackston, CD16; Robert Bruce, CD17; Margie Forster, CD18; Scott Mann, CD19; Marian K. Stanko, CD20; Curtis Nelson, CD21; Tina Gibson, CD22; Ken Muenzler, CD23; Alexander Kim, CD24; Virginia Abel, CD25; John Dillard, CD26; Tom Knight, CD27; Marian Knowlton, CD28; Rex Teter, CD29; Christopher Suprun, CD30 Jon Jewett, CD31; Susan Fischer, CD32; Lauren Byers, CD33; William "Bill" Greene, CD34; Mary Lou Erben, CD35; and Janis Holt, CD 36.

5 answers


01. Cliff Edwards/Disney Studio Chorus - When You Wish Upon a Star ( Pinocchio) *03:14

02. Carmen Twillie/Lebo M - Circle of Life (The Lion King) *04:01

03. Samuel E. Wright - Kiss the Girl (The Little Mermaid) *02:42

04. Judy Kuhn - Colours of the Wind (Pocahontas) *03:34

05. Phil Harris/Bruce Reiterman - The Bare Necessities (The Jungle Book) *04:55

06. Randy Newman - You've Got a Friend in Me (Toy Story) *02:04

07. Amy Adams - That's How You Know (Enchanted) *03:49

08. Ernie Sabella/Jason Weaver/Joseph Williams/Nathan Lane - Hakuna Matata (The Lion King) *03:13

09. Samuel E. Wright - Under the Sea (The Little Mermaid) *03:13

10. Angela Lansbury - Beauty and the Beast (Beauty and the Beast) *02:45

11. Brad Kane/Lea Salonga - A Whole New World (Aladdin) *02:41

12. Klaus Badelt - He's a Pirate (Pirates of the Caribbean. The Curse of the Black Pearl) *01:30

13. Ilene Woods - A Dream Is a Wish Your Heart Makes (Cinderella) *03:18

14. Robin Williams - Friend Like Me (Aladdin) *02:26

15. Jason Weaver/Laura Williams/Rowan Atkinson - I Just Can't Wait to Be King (The Lion King) *02:50

16. Susan Egan - I Won't Say (I'm In Love) (Hercules) *02:22

17. Bill Shirley/Mary Costa - Once Upon a Dream (Sleeping Beauty) *02:44

18. Jodi Benson - Part of Your World (The Little Mermaid) *03:13

19. Tawatha Agee/Vaneese Thomas/Cheryl Freeman/LaChanze/Lillias White/Roz Ryan - Zero to Hero (Hercules) *02:20

20. Julie Andrews/Dick Van Dyke - Supercalifragilisticexpialidocious (Mary Poppins) *02:03

21. Phil Harris/Thurl Ravenscroft/Scatman Crothers - Ev'rybody Wants to Be a Cat (The Aristocats) *02:06

22. Sally Dworsky/Joseph Williams/Kristle Edwards/Nathan Lane/Ernie Sabella - Can You Feel the Love Tonight (The Lion King) *02:58

CD2

01. Judy Kuhn - Just Around The Riverbend (Pocahontas) *02:28

02. Brad Kane - One Jump Ahead (Alladin) *02:22

03. Amy Adams - Happy Working Song (Enchanted) *02:09

04. Angela Lansbury/Jerry Orbach - Be Our Guest (Beauty And The Beast) *03:44

05. Ed Wynn/Jerry Colonna/Kathryn Beaumont - The Unbirthday Song (Alice In Wonderland) *01:54

06. The Cast Of "High School Musical" - Breaking Free (High School Musical) *03:25

07. James Baskett - Zip-A-Dee-Doo-Dah (Song Of The South) *02:16

08. Mark Keali'i Ho'omalu/North Shore Childrens Choir & Key Cygnetures - Hawaiian Rollercoaster (Lilo & Stitch) *03:28

09. Danny Elfman - What's This? (Nightmare Before Christmas) *03:05

10. Julie Andrews - A Spoonful of Sugar (Mary Poppins) *04:09

11. The Dwarf Chorus - Dig Dig Dig/Heigh-Ho Medley (Snow White) *02:47

12. Disneyland Chorus - It's a Small World *03:02

13. Louis Prima/Phil Harris/Bruce Reitherman - I Wanna Be Like You (The Jungle Book) *04:39

14. Sarah McLachlan - When She Loved Me (Toy Story 2) *03:04

15. Tigger - The Wonderful Thing About Tigger (The Tigger Movie) *00:40

16. Mandy Moore & Zachary Levi - I See the Light (Tangled') *03:44

17. Jonatha Brooke - I'll Try (Return To Neverland) *04:06

18. Peggy Lee/Si & Am - The Siamese Cat Song (Lady And The Tramp) *02:14

19. Disney Chorus - Yo Ho! (A Pirate's Life for Me) *01:17

20. Mandy Moore - When Will My Life Begin (Tangled) *02:32

21. Betty Noyes - Baby Mine (Dumbo *02:07

22. Disney Studio Chorus/Bill Thompson/George Givot - Bella Notte (Lady And The Tramp) *02:36

CD3

01. Adriana Caselotti - Some Day My Prince Will Come (Snow White') *01:54

02. Hannah Montana - The Best Of Both Worlds *02:54

03. Matthew Garber/Dick Van Dyke/Julie Andrews/Karen Dotrice - Chim Chim Cher-ee (Mary Poppins) *02:46

04. Verna Felton - Bibbidy Bobbody Boo (Cinderella) *01:24

05. Liz English/Gary Dubin/Dean Clark - Scales And Arpeggios (The Aristocats) *01:40

06. Disneyland Chorus - Pink Elephants on Parade (Dumbo) *02:29

07. Christine Aguilera - Reflection (Pop Version - Mulan) *03:34

08. Jocelyn Brown - A Star Is Born (Hercules) *02:04

09. Ilene Woods/Mike Douglas - So This Is Love (Cinderella) *01:32

10. Randy Newman - We Belong Together (Toy Story 3) *04:02

11. Adriana Caselotti - Whistle While You Work (Snow White) *03:25

12. Peggy Lee - He's A Tramp (Lady & The Tramp) *02:25

13. Mickey Mouse Club - Mickey Mouse March (Mickey Mouse Club) *02:41

14. Cliff Edwards/Dickie Jones - Give A Little Whistle (Pinocchio) *01:36

15. Bill Lee - Cruella Deville (101 Dalmations) *03:39

16. Anika Noni Rose - Almost There *02:24

17. Kathryn Beaumont/Bobby Driscoll/Paul Collins/Theh Jud Conlon Chorus/Tommy Luske - You Can Fly (Peter Pan) *04:28

18. Disney Studio Chorus - Little April Showers (Bambi) *03:54

19. Samuel E Wright - They Live in You (The Lion King Broadway Show) *03:04

20. Pearl Bailey - Best Of Friends (The Fox And The Hound) *02:14

21. Vinx/Lebo M - Digga Tunnah (Dance) (The Lion King 1.5) *03:53 22. Hayley Mills - Let's Get Together (The Parent Trap) *01:31

23. Mouseketeers - Mickey Mouse Club, Alma Mater (Mickey Mouse Club) *01:47

1 answer


Cytotoxic T cell's primary responsibility is to kill infected cells. I'll start from the beginning.

From a progenitor cell in the bone marrow, the T cell will begin maturation in the thymus. In the thymus it begins in the cortex as a pro T cell. In this stage it is considered a double negative cell (I'll explain more later). Here it has the beta chain (V,D,J's) rearranged. Next it becomes a pre T cell. By now the T cell has finished rearranging its beta chain and now begins rearrangement of its alpha chain.

Both the beta and alpha chain under go allelic exclusion. This prevents one of the alleles from being expressed (this would be mom's or dad's). If the pro T cell made a beta chain from your mothers allele, your father's allele would be suppressed. This is an important feature, otherwise you could accidentally make a stop codon and that would stop your T cell development right there.

So as a pre T cell it continues to proliferate and it upregulates CD3, CD4 and CD8. You have two types of T cells that it can mature to. CD4 and CD8. A CD4 T cell is also known as a helper T cell and a CD8 T cell is also called a cytotoxic T cell. They function very differently but at this point the T cell doesn't know which one it will become. Therefore it is at this juncture a double positive thymocyte.

The next phase is an immature T cell. Here the alpha chains have finished rearrangement (also allelic exclusion applies here). Now the cell will undergo positive and negative selection. The immature T cell is tested by thymic epithelial cells (TEC). TEC's have a unique feature that belongs to professional antigen presenting cells (APC's) and that is expressing both MHC class I and MHC class II on its cell surface. An immature T cell that can bind to a TEC's MHC class I or MHC class II is positively selected to continue maturation. This is an important step because ensures that your T cells are specific for your body's MHCs. However, if the immature sticks too strongly, it will be neglected and eventually die. You don't want a mature T cell that binds way too strongly on your own cells either. Those that don't bind at all will also die by neglect. The strict standards ends up killing about 95% of all maturing T cells. The immature T cell that was capable of binding to MHC class I molecule is signaled to become a CD8 or cytotoxic cell and the immature T cell that was capable of binding to MHC class II molecule is signaled to become a CD4 or helper T cell.

Now that your immature T cells have been primed to your own body, it will undergo negative selection. In this process it is exposed to other types of cells, dendritic cells and macrophages. Dendritic cells and macrophages are part of your APCs. If the T cell binds too strongly it will also die by neglect.

Congratulations! Your immature T cell is now a mature naive T cell. It is now ready to leave your thymus and it will be stored mainly in your lymph nodes to await an infection.

Now that your cytotoxic T (CD8) cell has been made, it waits in your lymph node for an infection. A dendritic cell (remember these guys? they are present all over your body) will come in through an afferent lymphatic vessel from the source of infection. An important feature of cytotoxic T cells is that it targets cytoplasmic infection, or more specifically viruses. Generally viruses proliferate within a cell and antibodies cannot get to them if the virus is residing inside one of your own cells. So the dendritic cell gets infected and travels through the afferent lymphatic vessel into your lymph nodes. Here waits all of your adaptive immunity responses. It's an ambush! Your cytotoxic cells have been waiting for this moment. The cytotoxic cell that is specific for the antigen that is presented on the dendritic cell latches on. There are two signals that activate the cytotoxic (CD8) cell. B7 from the dendritic cell attaches to CD28 on the cytotoxic T cell and CD8 attaches to the dendritic cell. The cytotoxic cell is now activated and it is now on a mission to destroy. It secretes IL-2 which binds to itself. This is an autocrine function that signals the cytotoxic cell to replicate like crazy. Your army travels out through the efferent lymphatic vessel into your blood stream. Eventually it arrives to the cells that are infected. It is capable of binding to the same antigens that it first recognized from the dendritic cell that brought it inside initially. It latches on with CD8 and releases its' weapons. Perforin is released which punches holes into the cell and granzymes are also released which induces apoptosis (cell death). Memory T cells are also made to fight against future infection. These are long lasting cells. Your other T cells (remember them?) the helper T cells come by and deactivate your cytotoxic T cells with FasR and CTLA-4.

Hope that helps.

11 answers


Bronchiolitis Obliterans Organizing Pneumonia

Bronchiolitis obliterans organizing pneumonia (BOOP) was described in 19851 as a distinct entity, with different clinical, radiographic, and prognostic features than the airway disorder obliterative bronchiolitis2 and the interstitial fibrotic lung disorder usual interstitial pneumonia/idiopathic pulmonary fibrosis (UIP/IPF).3 BOOP is characterized by polyploid endobronchial connective tissue masses composed of myxoid fibroblastic tissue resembling granulation tissue filling the lumens of terminal and respiratory bronchioles and extending in a continuous fashion into alveolar ducts and alveoli, representing an organizing pneumonia (Figure 1).1-3 Other histological features include central clusters of mononuclear inflammatory cells possibly found in the intraluminal polyps (the polyps appear to float freely within a bronchiole or are focally attached to the wall), chronic inflammation in the walls of the surrounding alveoli with reactive type II cells, increased foamy macrophages in the alveoli, and preserved lung architecture.2

BOOP continues to be reported throughout the world.4-7 Most patients have idiopathic BOOP, but there are several known causes of BOOP, and several systemic disorders have BOOP as an associated primary pulmonary lesion (Table 1). The BOOP pattern might also occur as a secondary process in several clinical settings, such as the inflammatory-appearing lesion of UIP/IPF, with Wegener granulomatosis, in the walls of lung abscesses, around lymphoma or other neoplasms, and with bronchiectasis. In these patients, the underlying process is the primary cause of symptoms and the subsequent clinical course.

The terms organizing pneumonia and cryptogenic organizing pneumonia are sometimes used for the broad category of patients with organizing pneumonia. There are several reasons that the term BOOP should continue to be used for the clinical disorder and corresponding pathological lesion described in this review. First, investigators and clinicians throughout the world recognize the clinical and pathological features of this disorder, and they commonly use the term BOOP. Second, BOOP is a histological process that involves distal airways and alveoli simultaneously. Although various lung diseases represent a chronic inflammatory process, it is now apparent that the processes differ markedly among various diseases, such as chronic obstructive pulmonary disease, asthma, and BOOP, with different inflammatory cells, mediators, inflammatory effects, and response to treatment.8 Therefore, an inflammatory lesion that involves only airways or only alveoli may have different inflammatory components than the BOOP lesion that involves airway and alveoli simultaneously. Third, investigations of specific treatments for BOOP will be more strongly positive if the specific definition of BOOP is used for inclusion of patients rather than using the broad definition of organizing pneumonia. This is similar to IPF, in which many distinct histological disorders were included in this category in the past, resulting in dilution of the actual mechanism and poor treatment results. Now that IPF is limited to UIP,3 the opportunity to fully characterize the fibrotic pathway is much greater, and antifibrotic treatment tailored to this fibrotic pathway will be tested more efficiently and accurately.

Pathogenesis of BOOP

BOOP is an inflammatory lung disease and thus is related to the inflammatory pathway rather than the fibrosing pathway that occurs with UIP/IPF. The inflammatory response associated with disorders such as asthma, chronic obstructive pulmonary disease, granulomatous diseases, and BOOP have common features of the sequential inflammatory response, yet these disorders seem to have differences that have not yet been fully characterized. These differences are important because treatment directed toward one type of inflammatory response might not be effective against another type.8

There is newly formed fibromyxoid connective tissue in BOOP and UIP/IPF; in BOOP it can be completely reversed by corticosteroid therapy, but in UIP/IPF this tissue participates in the remodeling and destruction of the interstitium.9, 10 Reasons for the response to corticosteroid in BOOP and the destruction in UIP/IPF remain unknown.11 There seems to be abundant capillarization in the intra-airway fibromyxoid lesions in BOOP compared with minimal vascularization in UIP/IPF.9 This might be because of vascular growth factors in BOOP that will result in normal apoptosis (natural-occurring cell death) in BOOP but not in UIP/IPF. Results of an additional study10 showed that the apoptotic activity is higher in the fibromyxoid lesion of BOOP compared with UIP/IPF, suggesting that apoptosis has an important role in the resolution process of the newly formed connective tissue in BOOP.

Diagnosing BOOP

Lung biopsy continues to be the preferred method for establishing a diagnosis. The video-assisted thoracoscopic procedure has become the established technique. In a study12 of 49 patients who underwent the video-assisted thoracoscopic procedure for interstitial lung disease, the mean length of the operation was 45 minutes, the chest tube was inserted for 1.3 days, there were no deaths, there were no reexplorations, and none were converted to an open thoracotomy.

Radiographic findings of BOOP

The typical chest radiograph shows bilateral patchy (alveolar) infiltrates (Figure 2A). Cavities are rare, although 4 of 5 patients with a single pulmonary nodule had cavitation.13 Effusions are rare. Linear opacities occurring at the bases are usually associated with a poorer prognosis; however, a study6 of BOOP in 23 patients in Korea indicated recovery in all patients regardless of their radiographic findings. Generally, the infiltrates gradually enlarge from their original site or new infiltrates appear as the clinical course progresses; however, migratory or "mobile" pulmonary infiltrates have been reported6, 14, 15 in 10% to 25% of patients. Unilateral BOOP also has been reported.16, 17

The chest computed tomographic scan shows findings similar to the chest radiograph, with bilateral areas of consolidation and ground glass opacities, usually with a peripheral location (Figure 2 B). Costabel et al15 reported that sometimes the peripheral opacities are in the form of triangles, with the base of the triangle along the pleural surface and the tip of the triangle toward the mediastinum (Figure 2 C). In a study18 from England, high-resolution chest computed tomographic scans showed 2 types of linear opacities: the first extends in a radial manner along the line of the bronchi toward the pleura and the second occurs in a subpleural location with no relation to the bronchi. Both types usually occur in the lower lobes, frequently associated with multifocal areas of consolidation, and usually completely resolve with treatment.

Treatment of BOOP

Prednisone, with its potent anti-inflammatory property, continues to be recommend as first-line treatment for patients with symptomatic and progressive disease. Patients with asymptomatic mass lesions or nonprogressive disease can be observed and treated at a later time if needed. The dosage is generally 1 mg/kg (60 mg/d) for 1 to 3 months, then 40 mg/d for 3 months, then 10 to 20 mg/d or every other day for a total of 1 year. Every-other-day scheduling can be successfully used for this disorder. A shorter 6-month course may be sufficient in certain situations. Total and permanent recovery is seen in most patients and is somewhat dependent on the cause or associated systemic disorders. Anecdotally, erythromycin, inhaled triamcinolone, and cyclophosphamide have been used to treat BOOP.19-21 Epidemiological studies of these agents have not yet been performed for confirmation of efficacy.

Recurrence of BOOP

In patients treated for less than 1 year, BOOP might recur in one third. It is a lung disorder that can be successfully treated a second and third time with the previously responsive dosage level of prednisone.1 Relapse of BOOP may be related to the severity of the illness. In a group of 7 patients who had a relapse it was found that the level of hypoxemia at the time of diagnosis was the most important determinant of relapse22; however, Cordier11 did not find this relation.
For patients who do not respond to treatment, it is important to determine if the BOOP pattern is primary or secondary. On close evaluation by a lung pathologist, the biopsy specimen that shows the BOOP pattern might also show the typical leading edge of "fibroblastic foci" that indicates UIP/IPF. The BOOP pattern might respond to corticosteroid therapy, yet the fibrotic process of UIP/IPF is the driving force of the progressively deteriorating clinical course.

Types of BOOP

Idiopathic BOOP is the most common type.1 A flulike illness, fever, and an increased erythrocyte sedimentation rate continue to be typical findings of this form of BOOP. Cough and dyspnea are common but generally mild. Hemoptysis is uncommon, although it has been reported in 2 patients as a presenting symptom23 and in some patients with nodules.13, 24 Crackles occur in two thirds of patients. Pneumothorax has occurred as a complication of BOOP in one patient with an effusion,25 one with a solitary nodule,26 and another with respiratory distress.27 Results of pulmonary function studies show mildly to moderately decreased vital capacity. The flow rates are normal except in smokers. The diffusing capacity is decreased in almost all patients, although generally mildly to moderately. The prognosis of idiopathic BOOP remains good, some patients resolve without treatment, and 65% to 80% of patients treated with corticosteroid therapy are cured.

Rapidly Progressive BOOP can occur in a small percentage of patients, but it is a deadly form of the disease.28, 29 In some of these patient reports, there was an underlying fibrotic process as the cause of the ultimate fatal course, with BOOP as a secondary component, yet some patients seemed to have a primary, rapidly developing BOOP, which had a better prognosis. This form of BOOP occurs equally in men and women and at all ages. It can occur in healthy, vigorous individuals or can be associated with other systemic disorders. The course can be rapid, with 1 to 3 days of symptoms and acute respiratory failure. Patients might present with adult respiratory distress syndrome, with pathological findings indicating an organizing adult respiratory distress syndrome pattern with the appearance of BOOP.30 Clinically, rapidly progressive BOOP can be indistinguishable from acute interstitial pneumonia.31, 32 Early histological diagnosis of the primary BOOP lesion and initiation of corticosteroid therapy might improve survival in these patients.29

Focal Nodular BOOP was reported33 in 1989 in 5 of 16 patients with idiopathic BOOP. Since then it has become a clinically important process, especially because it might be indistinguishable from carcinoma of the lung.13, 26, 34-36 Although some focal nodular lesions might progress to the typical bilateral process of idiopathic BOOP, most do not, and resection results in a cure.

Multiple Nodular Lesions can also occur,34, 35 and most regress spontaneously. Of 12 patients with multiple large nodules or masses, all had complete resolution of their symptoms, 10 with no therapy and 2 after corticosteroid therapy.34 In these patients, pleuritic chest pain was the most common presenting symptom, occurring in 50%. The number of masses varied from 2 to 8 (mean, 5). The authors concluded that BOOP should be considered when multiple large nodular lesions have chest computed tomographic findings showing air bronchograms, irregular margins, broad pleural tags, parenchymal bands, or subpleural lines.

Clinician investigators36 in New Orleans suggest that BOOP may have a connection to reports of spontaneous regression of lung metastases. They concluded that a major reason that reports of spontaneous regression of lung metastasis have decreased in recent years is the increasing emphasis on obtaining diagnostic tissue of multiple nodular lesions for lung metastasis, many of which have proven to be BOOP.

Postinfection BOOP can develop after a variety of different types of infectious pneumonias,11 including those caused by bacterial agents such as Chlamydia,37 Legionella, and Mycoplasma pneumoniae38 and viral agents such as parainfluenza virus16 and adenovirus.39 Parasitic infections such as malaria40 and fungal infections, including Cryptococcus neoformans41 and Pneumocystis carinii,42 have also been reported as a cause of the BOOP lesion.

Generally for these patients, there is initial improvement of the infectious pneumonia with use of appropriate antimicrobial agents, but after a few days, it becomes apparent that the symptoms and radiographic findings persist. The pneumonia process has now become organized into the BOOP lesion. Corticosteroid treatment at this point is almost always successful.

Drug-related BOOP has been reported11, 15 from use of several different types of medications, including anti-inflammatory and immunosuppressive agents such as bleomycin sulfate, gold, and methotrexate; antibiotics such as sulfasalazine, sulfamethoxypyridazine, cephalosporins, and amphotericin B; illicit use of cocaine; and a massive dose of L-tryptophan. Minocycline-associated BOOP has been reported43 in a woman who was taking this medication for acne. Descriptions of amiodarone-related BOOP continue to be reported.44 Phenytoin-related BOOP with rapid improvement after corticosteroid therapy has been reported.45 There has been a report46 of a woman who developed carbamazepine-induced lupus erythematosus and associated BOOP, both of which responded to corticosteroid therapy. There has been a report47 of ticlopidine hydrochloride, an inhibitor of platelet aggregation, associated with BOOP that resolved after withdrawal of the agent. BOOP has now been added to the spectrum of pulmonary lesions associated with nitrofurantoin.48

Rheumatologic or connective tissue BOOP is clinically similar to the idiopathic form and has been reported49-57 with all of the connective tissue diseases. BOOP represents the patchy infiltrative lesions seen in patients with lupus erythematosus, rheumatoid arthritis, Sjögren syndrome, and dermatomyositis. The process often responds to corticosteroid therapy, unlike the fibrotic process that may occur in these disorders.

There has been a report of a patient with BOOP associated with dermatomyositis that was resistant to corticosteroid therapy; with initiation of cyclophosphamide therapy, there was improvement of pulmonary and cutaneous findings.52 BOOP can also occur in patients with ankylosing spondylitis,53 polymyalgia rheumatica,54, 55 and Behçet disease56 and might be the first manifestation of a connective disorder.57

Immunologic disease BOOP has been reported with common variable immunodeficiency syndrome58 and essential mixed cryoglobulinemia.59

Bone marrow transplantation BOOP has been described in patients who underwent allogeneic marrow transplantation. There has also been a report of BOOP in a patient who received a syngeneic bone marrow transplant from his twin brother.60 There is an additional report of a patient who developed ulcerative colitis and BOOP 7 months after receiving a bone marrow transplant from his brother.61 It was not clear whether the BOOP was associated with the ulcerative colitis or from another cause, such as a cytomegalovirus infection. Too few reports have been published to determine whether BOOP in these patients is an incidental finding or represents a complication of bone marrow transplantation.

Lung transplantation BOOP has been reported62, 63 in 10% to 28% of lung transplant recipients. The lesion generally occurs 1 to 10 months after transplantation and is usually associated with the acute rejection reaction. The process is reversible for most of these patients, especially if the underlying acute rejection is successfully treated. The BOOP lesion may occur before the onset of obliterative bronchiolitis,62 and whether this is a risk factor for lung transplantation obliterative bronchiolitis has not been established, but it is prudent to treat the BOOP reactions aggressively in these patients. Cytomegalovirus pneumonia-associated BOOP has also been described63 in lung transplant recipients and is generally responsive to corticosteroid therapy.

Renal transplantation BOOP has been described64 in 1 patient 12 weeks after transplantation. A rapid recovery occurred after an increase of the daily dose of methylprednisolone.

Radiotherapy BOOP has become an important clinical disorder in patients receiving radiotherapy to the breast.65-68 Symptoms might occur 1 to 12 months after completion of radiotherapy. Symptoms might be minimal, but most patients have fever, nonproductive cough, and mild shortness of breath. The chest radiograph shows peripheral patchy or alveolar infiltrates, often outside the radiation field.66 One study68 indicated that all 11 patients studied had spontaneous migration of infiltrates from the irradiated lung to the contralateral nonirradiated lung with no nodular or reticular lesions. There can be a dramatic improvement with corticosteroid therapy, but relapses may occur.66, 67 Some investigators66, 68 have suggested that radiotherapy may "prime" the development of BOOP. Bronchoalveolar lavage studies of these patients indicate an increase in lymphocytes, mast cells, CD3 cells, and CD8 cells and a decrease in CD4 cells and the CD4-CD8 ratio68; however, the underlying mechanism remains unknown.

Environment-related BOOP continues to be reported rarely. In 1992, textile printing dye-related BOOP was described in 22 textile airbrush workers.69 Six died initially. Follow-up of some of the workers indicated gradual improvement over time.70 It has been suggested69 that the cause was related to the spraying of a respirable aerosol into the distal airways and alveoli; however, the reactive chemical agent and mechanism remain unclear. It is also not known whether the organizing pneumonia was a de novo process or resulted from the late organization of pulmonary edema.69 Penicillium mold dust-related BOOP has been described71 in a patient who developed BOOP after inhalation of powdery dust of a growth of Penicillium janthinellum mold on the top of a discarded orange juice container. Smoke inhalation BOOP has been reported72 in a patient who was in a house fire and had erythema nodosum.

Miscellaneous BOOP continues to be reported, eg, in association with myelodysplastic syndrome,73 Hunner interstitial cystitis,74 chronic thyroiditis,75 alcoholic cirrhosis,75 and, in England, seasonal syndrome with cholestasis.76 It has been reported in patients with human immunodeficiency virus infection,77 with one report during pregnancy.78 Inflammatory bowel disease-related BOOP has been described79 as an important treatable disorder in these patients. The BOOP lesion might be associated with lymphoma, and an atypical course of what is thought to be idiopathic BOOP may indicate a neoplastic process such as a lymphoma.80 Recurrent BOOP responsive to prednisone treatment has been reported in T-cell leukemia.81, 82 BOOP has also been reported in primary biliary cirrhosis83 and after coronary artery bypass graft surgery.84

Conclusion

The busy clinician will see patients with a febrile illness and patchy infiltrates who have not responded to antibiotic drug therapy. The patient might have BOOP. Sometimes this disorder is treated in the hospital, but it is generally managed on an ambulatory basis. Typical idiopathic BOOP is characterized by a flulike illness, bilateral crackles, and patchy infiltrates and can be cured in 65% to 80% of patients with prednisone therapy. BOOP has become an important consideration in the diagnosis of focal nodular lesions. Postinfectious pneumonia BOOP remains a treatable process. BOOP occurs in virtually all of the connective tissue disorders and generally responds to corticosteroid therapy. It is an important treatable inflammatory lung disease.

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