adaptive immunity

A collective and coordinated response to the introduction of foreign substances in an individual mediated by the cells and molecules in the immune system.Adaptive immunity response mediated by :

1- antibody to eliminate extra cellular pathogen (humeral immunity).

2- cell-mediated immunity for intracellular pathogen which required T-cell .

Strategic location
Skin (SALT(
Mucous membranes (GALT, NALT, BALT(
Lymphoid organs (Lymph nodes, spleen(
Blood circulation (plasmacytoid and myeloid DC(
Pathogen capture
-Phagocytosis (whole microbe(
-Macropinocytosis (soluble particles(cell drinking
Diversity in pathogen sensors (PRRs(toll like R
Extracellular pathogens (bacteria(
Intracellular pathogens (viruses(
T-cell express either CD4 or CD8 Surface marker which can be used to define the major sub population of T-cell:
1. CD4 characterize the helper T-cell population and produce cytokine and coordinate of immune response.it is called helper because it help B cells and other T cells to multiply & differentiated in to effector cells.

T helper( CD4) recognize Ag associated with MHC II molecules which processed and presented by APC , after Ag recognition CD4 activated
and further subdivided in to TH1,TH2,TH17 and T reg cell based on their cytokines and functional activity.