Principles of Immunology Immunodeficiency 4/20/06 ”Wise people talk because they have something to...

Principles of Immunology

Immunodeficiency4/20/06

”Wise people talk because they have something to say; fools, because they have to say something”

Plato

Word/Terms List

AIDS SCID Primary immunodeficiency Secondary immunodeficiency

Immunodeficiency

Primary-usually genetic, congenital

Secondary-Acquired

Mechanisms of Immunodeficiency

Loss or reduction of: Cell type Cell numbers Cell function

Loss of Cell Function

Receptors Cell signaling Cytokine production Ig production Co stimulation impairment Intracellular killing Extravasation impairment

Primary Immunodeficiency Myeloid lineage

Congenital agranulocytosis Leukocyte-adhesion deficiency

Lymphoid lineage Severe combined immunodeficiency (SCID) B cells

Agammaglobulinemia Hypogammaglobulinemia Specific Ig Deficiencies

T cells DiGeorge Syndrome Wiskott Aldrich Syndrome

Secondary Immunodeficiency

Drug related Disease related

Cancer AIDS

HIV T helper cell as target

SCID

Various genetic defects No TCR or defective TCR Defective cell signaling Defective IL 2

Recurrent infections Death at early age

Wiskott Aldrich Syndrome X linked disorder Affects platelet numbers/function Affects T cell function Cytoskeleton of lymphocytes affected

Lower amounts of IgM Increased susceptibility to certain

bacterial infections

Bruton’s Agammaglobulinemia

Low levels of IgG B cell signal transduction affected Defective BCR

Recurrent bacterial diseases starting at end of first year of life

Short life span

DiGeorge Syndrome

Poorly developed or functioning thymus

Associated with other developmental conditions

Depression of T cell numbers Absence of T cell response Humoral response to T independent

antigens only

Secondary Immunodeficiency

Drugs Irradiation Cancer AIDS

AIDS

HIV as agent T helper as target cell Attacked by own CD8 cells Susceptible to opportunistic infections

Kaposi’s sarcoma CMV Candida Pneumocystis carinii