Cell Bio Lecture Notes Immunology C23 p. 1195-1206

Nonspecific surface, nonspecific interior, specific interior(immune system).

2 branches of immune response: Humoral (liquid portion of blood;antibodies) Cell-mediated(T)

Hallmarks of immune response: memory and specificity. "Nonspecific immunity is an oxymoron"(self-contradictory). However, specificity not absolute and nonspecifics interact.

Circular definitions: Antigen is foreign molecule that provokes antibody (and immunosompetent cell) production. Antibodies are proteins produced in response to antigenic exposure.

Immunoglobulins: insoluble proteins that precipitate with the globulin fraction. Opsonization: coating in prep. for phagocytosis. Antibodies and complement components opsonize.

Bone marrow: all blood cells created here. Bursa of Fabricius: terminal B cell differentiation (fowl.) Bursal equivalent in humans = bone marrow itself. T cells term. differentiation thymus.

Positive, negative selection in thymus. Must respond to self, not too strongly.

APC +T_H(CD4⁺) + B cell(clonal selected) to get antibody, memory B cells.

T_C (CD8⁺) kill infected cells Recognize foreign antigen cradled by class I molecule (MHC-encoded)

Lymphocyte recirculation necessity. Targeting to high endothelial venules.