Core Immunology - Immunodeficiency (12) Flashcards Preview

Clinical Pathology > Core Immunology - Immunodeficiency (12) > Flashcards

Flashcards in Core Immunology - Immunodeficiency (12) Deck (25):
1

B lymphocytes

Develop potential to secrete antibodies (humoral immunity)

2

Killer/cytotoxic T lymphocytes

Able to kill (cellular immunity)

3

Helper T lymphocytes

Secrete growth factors/cytokines which control immune response - help B lymphocytes and T lymphocytes

4

Which cells are the target of HIV?

Helper T lymphocytes

5

Supressor T lymphocytes

Dampen down immune response

6

Binding of antibodies to antigens inactivates antigens by...

- Neutralisation (blocks viral binding sites, coats bacteria) (phagocytosis)
- Agglutination of microbes (phagocytosis)
- Precipitation of dissolved antigens (phagocytosis)
- Activation of complement system (cell lysis)

7

How do cytotoxic T cells work?

- Bind to infected cell
- Perforin makes holes in infected cell's membrane
- Enzymes enters
- Infected cell is destroyed

8

Immunodeficiency

Clinical situations where the immune system is not effective enough to protect the body against infection

9

What age is immunodeficiency most common?

Can occur at any age, children and elderly are much more sensitive to infection

10

Primary immunodeficiency

Caused by genetic defects in individual components of the immune system

11

Secondary immunodeficiency

Effects of external factors

12

Primary immunodeficiency

- Very rare
- Diagnosed in early childhood, can present in adult life
- Recurrent infection

13

Secondary/acquired immunodeficiency

- Stress
- Surgery/burns
- Malnutrition
- Cancer (lymphoproliferative disease)
- Immunosuppressive effect of drugs (cancer therapy - lymphocytes/neutrophils)
- Irradiation
- AIDS
- Other infections e.g. measles, TB

14

Nitroblue tetrazolium test

- Incubate neutrophils with die and creates free oxidative neutrophils, if works blue > dark
- Used for chronic granulomatous disease and other diseases of phagocyte function

15

Chronic granulomatous disease

- Osteomyelitis (bone marrow inflammation)
- Pneumonia
- Swollen lymph nodes
- Gingivitis (inflammation of gum)
- Non-malignant granulomas
- IBD

16

Complement pathway test

- Incubate sheep RBC and patients serum
- Complement system should active > RBC lysis

17

Primary B-cell deficiencies

- Common variable immunodeficiency
- X-linked agammaglobulinaemia
- Autosomal recessive hyper IgM syndrome
- IgA deficiency
- IgG subclass deficiency
- Transient hypogammaglobuinaemia of infancy

18

Primary T-cell deficiencies

- Severe Combined Immunodeficiency syndromes
- Adenosine Deaminase deficiency
- Purine nucleoside phosphorylase deficiency
- MHC class II deficiency
- Wiskott-Aldrich syndrome

19

B cell defect

- Different degrees of loss of antibody secretion
- Recurrent bladder infection with pyogenic organisms
- Diagnosed around 1-2yrs, maternal IgG protection

20

Treatment for B cell defect

Antibiotics, then IV IgG for life

21

How serious is IgA deficiency?

Less serious then IgG, which is very serious

22

SCID

Defects in B and T cells

23

Treatment of SCID

Gene therapy or bone marrow transplantation (curative)

24

T cell defect

More dramatic as B cells need T cell help

25

Symptoms of T cell defect

Recurrent infection with opportunist infections, bacteria and viruses e.g. Fungi (candida), protozoa (pneumocystis)

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