Week 1 - Intro, Cells, and Organs of the Immune System

Which cytokines drive neutrophil production?

G-CSF, GM-CSF, IL-3.

What are mast cells, and where are they located?

Tissue-resident cells that release histamine; key role in allergy and defense against parasites.

What are plasma cells?

Differentiated B cells specialized for antibody secretion.

Function of T helper (CD4+) cells?

Secrete cytokines; help B cells, cytotoxic T cells, and macrophages.

Function of cytotoxic T lymphocytes (CD8+)?

Kill virus-infected or tumor cells.

Function of regulatory T cells (Tregs)?

Suppress immune responses; maintain tolerance.

What receptor do NK cells use to mediate antibody-dependent cell cytotoxicity (ADCC)?

Fc receptor CD16.

What are secondary lymphoid organs?

Sites where lymphocytes encounter antigen and mount responses (lymph nodes, spleen, MALT).

What are the two main compartments of the spleen?

White pulp (lymphoid tissue) and red pulp (filters blood cells).

What is the main function of lymph nodes?

Filter lymph, provide site for antigen presentation and lymphocyte activation.

What are high endothelial venules (HEVs)?

Specialized venules in lymph nodes that allow lymphocytes to enter from the blood.