Major Histocompatibility Complex
Also written as MHC.
It recognizes antigens presented on major histocompatibility complex (MHC) class II molecules and secretes cytokines (interferon-gamma, interleukin-2) to activate macrophages, cytotoxic CD8+ T-cells, and natural killer (NK) cells.
What our notes say
- It recognizes antigens presented on major histocompatibility complex (MHC) class II molecules and secretes cytokines (interferon-gamma, interleukin-2) to activate macrophages, cytotoxic CD8+ T-cells, and natural killer (NK) cells. (HIV and opportunistic infections)
- The major histocompatibility complex for cell recognition (Cellular Immunology MCQs: Questions and Answers)
- Downregulating MHC I: Many viruses reduce the expression of Major Histocompatibility Complex class I molecules on the surface of infected cells, preventing cytotoxic T lymphocytes (CTLs) from recognizing and killing the infected cells. (Microbial Metabolism, Structure, and Therapeutics — Notes)
- Antigen Presenting Cells (APCs) and Major Histocompatibility Complex (MHC) molecules work together in a sophisticated system to prevent the spread of infections through effective immune surveillance and response coordination. (Cellular Immunology MCQs — MCQ Bank)
Study material on Major Histocompatibility Complex
- Comprehensive Immunology Quiz — Antigen Recognition to MHC — MCQ Bank
- Cellular Immunology MCQs — MCQ Bank
- Comprehensive Immunology Quiz — T Cell Development, Memory & Innate — MCQ Bank
- Cellular Immunology MCQs: Questions and Answers
- Weekly Year 2: Cellular Immunology Exam - March 27, 2026 (Section A: MCQs)
- Weekly Year 2: Cellular Immunology Exam - May 29, 2026 (Sections B & C) — Essay Questions
Practice questions on Major Histocompatibility Complex
The Major Histocompatibility Complex (MHC) genes are highly polymorphic. What does 'polymorphic' mean in this context?
- They are highly conserved among individuals.
- They can switch their gene segments during development.
- They have multiple alleles within the population.
- They encode enzymes involved in antigen processing.
Answer: C. Polymorphism refers to the existence of multiple different alleles (variants) for a gene within a population. The high polymorphism of MHC genes ensures that a wide variety of peptides can be presented, contributing to population-level immunity.