Exam 4: Dr. Thomason Immunosuppressive Therapy Flashcards Preview

Immunology - DVM year 1 > Exam 4: Dr. Thomason Immunosuppressive Therapy > Flashcards

Flashcards in Exam 4: Dr. Thomason Immunosuppressive Therapy Deck (30):
1

What do long term immunosuppressive therapies cause?

Susceptibility to bacterial infections (common)
Overwhelming, unusual infections

2

What are the common infections that can occur with long term therapies?

Cystitis
Pyoderma
Pneumonia

3

What are the overwhelming, unusual infections that can occur with long term therapies?

Fungal (aspergiullus)
Protozoal (toxoplasma)
Parasitic (demodex)

4

What are mechanisms of immunosuppression?

Decrease antibody synthesis by plasma cells
Decrease antibody-cell binding affinity
Impair mononuclear phagocytic system cell destruction of antibody-coated cells

5

What are glucocorticoids?

Prednisone, prednisolone, dexamethasone
Mainstay of immunosuppressive therapy

6

What are the mechanisms of corticosteroids?

Once in the nucleus, it binds to specific DNA sequences
--Enhance/inhibit transcription of genes
--Induce or inhibit protein translation

7

What do glucocorticoids do?

Decrease antibody synthesis (days)
Decrease antibody cells binding affinity
Impair MPS (hours)

8

What do corticosteroids have effects on?

Complement and rapid down -regulation of Fc receptor expression on macrophages leads to the reduction of phagocytosis of opsonised cells

9

What are the additional immunosuppressive effects?q

Decrease egress of cells from the blood
Suppress macrophages and neutrophil bactericidal functions
Inhibit amplification pathways of the complement cascade
Decrease antigen presentation to Th cells
Anti-inflammatory properties

10

What are corticosteroids?

Very effective immunosuppressive agent and the mainstay treatment of most immune-mediated diseases

11

What are the acute side effects of glucocorticoid therapy?

Polyuria/polydipsia
Polyphagia
Panting
+/- GI ulcerations

12

What are the chronic side effects of glucocorticoid therapy?

Alopecia
Thin skin
Pot belly
Hepatomegaly
Muscle weakness

13

How does standard glucocorticoid therapy work?

Wean down dose
Ultimate goal is to remove all medications

14

Describe local-acting steroids

Local effect and fewer systemic side effects
Poor systemic absorption metabolized by the liver right after absorption

15

What is combination immunosuppressive therapy?

Increase immunosuppresion
Dose-sparing effect with side effects

16

What is an example of immunosupressive agent?

Azathioprine

17

What does azathioprine interfere with?

Purine synthesis

18

What does azathioprine lead to?

Production of fraudulent nucleotides

19

What does azathioprine do?

DNA and RNA syntheses are inhibited, and mitosis and cellular metabolism is disrupted
Reduction in lympocyten proliferation

20

What are side effects of azathioprine?

Myelosuppression
Acute pancreatitis
Hepatopathy
Gastrointestinal

21

How can you minimize side effects of prednisone and azathioprine?

Combination therapy of the 2

22

What does cyclosporine do?

Decreases antibody synthesis
--Impairs IL-2 production
--Reduces lymphocyte activation

23

What does suppressed IL-2 production due to cyclosporine reduce?

T cell, then B cell proliferation

24

What does cyclophosphamide do?

Cross-links DNA
Preventing DNA separation
Toxic to resting and dividing cells, particularly proliferating lymphocytes
Suppresses CMI and humoral immunity

25

What are cyclophosphamide side effects?

Myelosuppression
Gastrointestinal disease
Refractory cystitis or bladder neoplasia

26

What does vincristine do?

Binds to tubulin and disrupts assembly of the mitotic spindle in mitosis

27

What does vincristine do for IMTP?

Increases platelet counts

28

What can management of immune-mediated blood disorders?

High dose intravenous immunoglobulins

29

What does human intravenous immunoglobulin do?

Competitively inhibits the binding of canine IgG to monocytes by saturation of Fc receptors
Prevention of phagocytosis of antibody-coated erythrocytes and platelets

30

Describe human intravenous immunoglobulins

Minimal toxicity but very expensive
May increased risk of blood clots
Availability is an issue