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Flashcards in Immunology Deck (37):
1

Immune response against giardia

IgA and Th cells. Eosinophils more responsible for helminths vs the trophozoite giardia

2

Sirolimus MOA

Inhibits mTOR pathway, disupting IL-2 signal transduction, preventing G1 to S progression and lymphcyte proliferation

3

Rituximab MOA

Chimeric antibody that targets CD20, depleting B cells.

4

Function of Th2 cells

Promote humoral immune response by secreting IL-4 and IL-5, which activate B cells.

5

IL-1

produced by macrophages. Activates Th0 cells, promoting them to differentiate into Th1 and Th2. Endogenous pyrogen

6

IL-2

Produced by Th1 cells. Stimulates development of CD4+, CD8+, and B cells.

7

IL-3

Produced by Th cells. Stimulates growth and differentiation of bone marrow stem cells

8

IL-10

Produced by Th2 cells. helps regulate balance between Th1 and Th2 populations. Inhibits synthesis of interferon gamma, leading to decrease in Th1s.

9

IL-12

Synthesized by macrophages. Stimulates Th1 growth and evelopemnt.

10

IL-4

Produced by Th2 cells. Facilitates growth of B cells and Th2 cells. Stimulates antibody isotype switching.

11

Type I interferons

Interferon alpha and beta. Made by most cells when infected by virus. Signal infected and neighboring cells to ahlt protein synthesis if the cell is infected with dsRNA.

12

Type II interferons

Interferon gamma. Produced by T cells and NK cells. Promotes Th1 differentiation, increases MHC class II expression, increases intracellular killing by macrophages.

13

Hyper-IgM syndrome

Inability of B cells to isotype switch. Presents with lymphod hyperplasia and recurrent sinopulmonary infections.

14

Transplant rejection types

Hyperacute: occurs in minutes to hours due to preformed antibodies against graft in patient's blood. Results in gross mottling and cyanosis and thrombotic occlusion

Acute: occurs in first 6 mos due to induction of humoral/cellular activation of naive immune cells against donor antigens. Hmoral rejection results in CD4 deposition, nuetrophils, and neccrotizing vasculitis. Cellular response results in lymphocytic infiltratates and endotheliitis

Chronic: occurs in months to years due to chronic low grade immune response refractory to immunosuppressants; results in vascular wall thickeining/luminal narrowing and interstitial fibrosis and parenchyma atrophy

15

Langhans giant cell

T-cell activated macrophages with multiple nuclei organized peripherally in a horseshoe shape. Nonspecific finding in granulomatous conditions.

16

IL-8

Released by macrophages. Chemotactic for neutrophils. Induces phagocytosis in neutrophils once they have arrived

17

C3a

Anaphylotoxic (triggers histamine release from mast cells). Recruits and activates eosinophils and basophils, not neutrophils.

18

C4a

Anaphylotoxic (tirggers histamine release from mast cells)

19

C5a

Anaphyotoxic (triggers histamine release from mast cells). Recruits and activates neutrophils, monocytes, eosinophils, basophils

20

Natural killer cells

Destroy cells with decreased or absent MHC class I on surface, such as in virus-infected cells and tumor cells.

21

CD14

marker of monocyte-macrophage cell lineage

22

IL-5

Produced by Th2 and mast cells. Stimulates eosinophil prolferation and activation during parasitic infection

23

Immune defense against parasites

-parasite invades mucosa or blood
-IgG and IgE coat parasite and bind eosinophil via Fc receptor
-eosinophil degranulates and releases major basic protein that damages the parasite (antibody-dependent cell-mediated cytotoxicity)

24

T cell maturation

-subcapsular zone: double negative precursor

-cortex: double positive. Undergo positive selection to ensure have affinity for self MHC

-medulla: single positive for either CD4 or CD8. Undergo negative selection to ensure don't have excess affinity for self antigens and MHC

25

Features of sarcoidosis: epi, clinical, imaging, labs, path

Epi: young african americans

Clinical: cough, dysphea, chest pain

Imaging: bilateral hilar adenopathy and pulmonary reticular infiltrates

Labs: high calcium, high ACE

Pathology: noncaseating granulomas

26

HBeAg and anti-HBeAg

HBeAg in serum is a marker of viral replication and high infectivity. Anti-HBeAg in the srum indicates cessation of active viral replication and low infectivity.

27

leukocyte adhesion deficiency

Pathophys: failure to express CD18 integrin, leading to disordered leukocyte migration. Defects in several proteins including LFA-1.

Presentation:: delayed separation of umbilical cord stump. Omphalitis. Recurrent bacterial infections and impaired wound healing. Perirectal abscess a common finding.

Labs: Elevated white count.

28

chronic granulomatous disease

Pathophys: phagocytes can't make ROS

Presentation: opportunistic infections

Labs: Neutropenia

Diagnosis: neg nitroblue tetrazolium dye reduction test

29

Thymoma presentation

Associated with paraneoplastic syndromes: myasthenia gravis, pure RBC aplasia, hypogammaglobulinemia

30

Endotoxin of N meningitidis

Lipooligosaccharide - analagous to LPS found in most gram negs

31

Endogenous pyrogens

IL-1, IL-6, TNF-alpha

32

Treatment of Guillan Barre

plasmapheresis and immunoglobulin

33

hapten

molecule that an't elicit immune response on own because can't activate Th cells, but can elicit response when binds to a protein

34

Henoch-Schonlein purpora

vasculitis. Presents with palpable pruritic lesions of butt and legs, arthralgias, fever, malaise, episodic abdominal pain. Can cause renal failure with mesangial IgA deposition. C3 normal.

35

Complication of juvenile arthritis

Uveitis that can lead to blindness

36

Job syndrome

failure of Th cells to make interferon gamma. Presents with recurrent staph infections, eczema, high IgE.

37

Presentation of Kaposi's sarcoma

Cutaneous lesions. Can also affect lungs, GI tract, biliary tree. If GI involvement, can get hematochezia, hematemesis, melena