Immunopathology

Question 1

What are the surface markers of T, B and NK cells

Answer 1

T cells- CD4/CD8
B cells- CD 19
NK cells-CD 16

Question 2

what are the most numerous lymphocytes

Answer 2

T-cells (cd4 more) 70% followed by b cells and NK cells

Question 3

Macrophages cytokines

Answer 3

IL-1 and TNF a

Question 4

cytokines that inactivate macrophages

Answer 4

IL-10, TGF-B

Question 5

What activates the classic complement system pathway

Answer 5

antigen antibody complexes

Question 6

What activates the alternative complement system pathway

Answer 6

non immunologic stimuli ie by the invading microorganism directly

Question 7

whats the use of HLA typing and matching

Answer 7

predict tissue compatibility before organ transplantation

Question 8

Class 1 HLA antigens (MHC-1)

Answer 8

• found on all human cells
  -involved in tissue graft rejection
  -include: HLA-A, B,C
  -targeted by CD-8+ T cells

Question 9

Class 2 HLA antigens (MHC-2)

Answer 9

-found on immunocompetent cells: APCS; dendritic cells, macrophages b cells, Langerhans cells and some t cells
-include HLA-D
-targeted by CD4+ tcells

Question 10

HLA-B27 antigens

Answer 10

ankylosing spondylitis

Question 11

HSR-1

Answer 11

-Antibody mediated (IgE)
-immediate HSR
-exposure to ag 1st time upregulates igE on the surface of mast cells and basophils, 2nd exposure cross links 2 adjacent igEs causing degranulation and histamine release
EXAMPLES: Hay fever, Anaphylactic shock, allergic asthma, AngioedemA

Question 12

HSR-2

Answer 12

-ag-ab mediated: igG/igM
-ag is intrinsic component of the cell membrane or receptor attacked by antibodies activating ADCC, phagocytosis
-EXAMPLES: Acute transfusion rx, Haemolytic disease of the newborn, Grave’s disease

Question 13

HSR-3

Answer 13

-ag-ab complexed deposit in tissues/ Vessel walls where the activate complement and recruit neutrophils that release stuff that cause tissue damage ( PGs, kinins, free radicals, lysozomal enzymes)
EXAMPLES: SLE, serum sickness (immune complex rx to medicines that contain proteins to treat stuff😭), Arthus rx (acute vasculitis at the site of injection or bite) , snake venom

Question 14

HSR-4

Answer 14

delayed HSR
Tcell mediated
activation of antigen specific CD4+ memory Tcells
secrete IL-2, activates macrophages cd8+ tcells w kida
EXAMPLES: contact dermatitis, tubercelin rx

Question 15

what ensures a successful graft

Answer 15

-ABO cross matching
-HLA cross matching for as many HLA ags as possible

Question 16

Types of transplant rejection

Answer 16

-Hyperacute: w/in mins
-Acute: days to weeks post transplat
-Chronic: months to years post transplant

Question 17

Hyperacute graft rejection

Answer 17

Antibody mediated- preexisting AB to donor AGs
Localized arthus rx with acute inflammation an dfibrinoid necrosis of BVs

Question 18

Acute graft rejection

Answer 18

T cell mediated
infilteration f lymphocytes and macrophages

Question 19

Chronic graft rejection

Answer 19

antibody mediated vascular damage

Question 20

Graft VS host disease

Answer 20

-when immunocompetent cells are transplanted (BM transplant or whole blood transfusion in SCID pts) they attack the host cells as foreign and cause damage by:
1. CD8+cells
2. recruitment of macrophages by graft cd4+ tcells
TARGET organs: liver, skin, GI mucosa