a 31 year old female contracted HIV human immunodeficiency syndrome) Ordinarily harmless infections are deadly to her. Which answer below best explains how her antibody-response (b cell immunity) became weakened even though HIV primarily infects cells involved in T cell immunity?
A. Hiv destroys cytotoxic T cells and cytotoxic T cells play a central role in stimulating antibody production.
B. Hiv causes malfunction of memory T cells, and memory T cells stimulate B cells to produce autoantibodies.
C. HIV destroys helper T cells and helpers T cells play a central role in stimulating antibody production.
D. HIV causes malfunction of cytotoxic T cells, and cytotoxic T cells suppress B cell immunity.
My answer: B
Your answer is incorrect. The correct answer is C. HIV destroys helper T cells and helper T cells play a central role in stimulating antibody production.
To explain how HIV weakens the antibody response, we need to understand the role of helper T cells in the immune system. Helper T cells, also known as CD4+ T cells, are a type of white blood cell that play a crucial role in coordinating and regulating immune responses. They recognize antigens presented by infected cells and activate other immune cells, including B cells, to produce antibodies.
HIV primarily infects and destroys helper T cells, thereby impairing the immune system's ability to respond effectively to infections. As a result, the production of antibodies by B cells is significantly weakened. This means that infections that are ordinarily harmless can become deadly in individuals with HIV because their weakened antibody response makes it difficult for their immune system to fight off these infections.
Option A is incorrect because cytotoxic T cells are responsible for directly killing infected cells, not stimulating antibody production.
Option B is incorrect because memory T cells do not stimulate B cells to produce autoantibodies. Memory T cells are a subset of T cells that "remember" previous infections and can mount faster and stronger immune responses upon re-exposure to the same pathogen. Autoantibodies are antibodies that mistakenly target the body's own tissues, and their production is not directly related to memory T cells.
Option D is incorrect because cytotoxic T cells do not suppress B cell immunity. Instead, they play a role in cell-mediated immunity by directly killing infected cells.