A three-year-old male patient has a history of an underdeveloped cell-mediated immune system. Which of the following most likely contribute to this deficiency?
A) Hypoadrenalism
B) HIV infection
C) Type I diabetes mellitus
D) Thymus gland insufficiency and a lack of thymosin secretion

Question

Quizplus · Accepted Answer

The thymus gland plays a critical role in the development and maturation of T lymphocytes (which are important for cell-mediated immunity). Thymosin is a hormone produced by the thymus gland that is essential for T cell development. If the thymus gland is underdeveloped or not secreting enough thymosin, it can lead to a deficiency in cell-mediated immunity. Hypoadrenalism (A) and Type I diabetes mellitus (C) do not directly affect the immune system in this way. HIV infection (B) primarily affects the immune system by attacking and killing CD4+ T cells, which are needed for cell-mediated immunity, but this patient's immune system deficiency is due to underdeveloped thymus gland rather than HIV infection.

A Three-Year-Old Male Patient Has a History of an Underdeveloped