The Immune System Organs and Cells Quiz

Immune Response Cells

• Dendritic cells play a central role in the activation of B cells, Tc cells, and other cells that participate in the immune response.

Lymphocytes

• T cells and B cells constitute 5%-10% of peripheral blood lymphocytes and attack pathogens and abnormal cells.
• T cells are involved in cell-mediated immune response, which activates mainly T cytotoxic cells and macrophages.
• B cells are involved in humoral immune response, which activates mainly B cells.

Cell Characteristics

• Natural Killer (NK) cells lack surface markers or membrane-associated proteins from B or T lymphocytes and lack immunologic specificity and memory.
• Monocytes are part of the innate immune system, replenish resident macrophages and dendritic cells, and function in both innate and adaptive immunity.
• Dendritic cells are specialized phagocytic cells that stimulate lymphocytes and other immune cells to respond to pathogens.

Cell Movement and Inflammation

• Eosinophils move by amoeboid movement in the tissues as a hallmark of chronic inflammation.

Cell Populations

• Neutrophils are the predominant cells in pus, accounting for its whitish/yellowish appearance.
• Eosinophils are involved in combating multicellular parasites and certain infections.
• Macrophages and dendritic cells do not have antigen-specific receptors and assist other cells in the immune response.

Cell Locations

• Microglia are named based on their tissue location in the brain.
• Neutrophils constitute 50%-70% of circulating white blood cells.
• Lymphocytes are not involved in phagocytosis.

Leukocytes

• Kupffer cells are found in the liver and are involved in phagocytosis.
• Dendritic cells are classified as antigen-presenting cells.

Lymphoid Organs

• The primary function of the lymphoid organs in the body is to support the immune system by providing a site for lymphocyte development, activation, and proliferation.
• Lymphoid organs provide a site for immune cell activation, proliferation, and differentiation.

Lymphocyte Functions

• There are three populations of lymphocytes based on function and cell-membrane components: B cells, T cells, and NK cells.
• Plasma cells serve as the effector cells for the B cell lineage.
• Some progeny of B and T lymphoblasts differentiate into memory cells.

Immune Response

• Memory cells are responsible for the life-long immunity observed for many pathogens.
• The CD nomenclature was originally developed for leukocyte surface molecules.
• Monoclonal Abs that react with a particular membrane molecule are commonly used to identify and isolate specific cell populations.
• Lymphoid organs provide a site for immune cell activation, proliferation, and differentiation.