Which one of the following types of immunoglobulins is involved in inflammatory and allergic responses?

A. Macrophage: This is the correct answer. An activated monocyte is also known as a macrophage. Monocytes are white blood cells that can mature into macrophages when they move into tissues. Macrophages play a crucial role in the immune system by phagocytosing (engulfing and digesting) pathogens and cellular debris.

B. Lymphocyte: Lymphocytes are another type of white blood cell that plays a central role in the immune system. They include B cells, T cells, and natural killer cells. Lymphocytes are primarily involved in adaptive immune responses, such as antibody production (B cells) and cell-mediated immune responses (T cells).

C. Plasma Cell: Plasma cells are a type of B cell that produces antibodies (immunoglobulins). They are involved in the adaptive immune response, specifically in the production of antibodies that target specific pathogens.

D. Polymorphonuclear Leukocyte: This term typically refers to a group of white blood cells that have a multi-lobed nucleus. Neutrophils, eosinophils, and basophils are examples of polymorphonuclear leukocytes. They are involved in innate immune responses, including the phagocytosis of pathogens.

A. IgD: Immunoglobulin D (IgD) is found on the surface of B cells and serves as a receptor for antigen recognition during the immune response. Its exact function is not fully understood, but it plays a role in the activation of B cells.

B. IgE: Immunoglobulin E (IgE) is primarily associated with allergic responses and defense against parasitic infections. When an allergen enters the body, IgE antibodies trigger the release of histamine and other chemicals, leading to allergy symptoms. IgE is also involved in protecting against certain parasites.

C. IgG: Immunoglobulin G (IgG) is the most abundant immunoglobulin in the bloodstream. It provides long-term immunity by recognizing and neutralizing pathogens such as bacteria and viruses. IgG antibodies are involved in secondary immune responses and are transferred from mother to fetus, providing passive immunity.

D. IgM: Immunoglobulin M (IgM) is the first antibody produced during an initial immune response to an antigen. It is effective at agglutination (clumping) of pathogens. IgM antibodies are generally found in blood and lymph fluid and are the first line of defense during infections.