Diseases Caused By T Lymphocytes

T lymphocytes injure tissues either by triggering inflammation or by directly killing target cells (Fig. 18-5). Inflammatory reactions are elicited mainly by CD4+ T cells of the TH1 and TH17 subsets, which secrete cytokines that recruit leukocytes. In some T cell-mediated disorders, CD8+ CTLs kill target cells bearing class I major histocompatibility complex (MHC)-associated antigens. The T cells that cause tissue injury may be autoreactive, or they may be specific for foreign protein antigens that are present in or bound to cells or tissues. T lymphocyte-mediated tissue injury may also accompany strong protective immune responses against persistent microbes, especially intracellular microbes that resist eradication by phagocytes and antibodies.

A role for T cells in causing a particular immunologic disease is suspected largely on the basis of the demonstration of T cells in lesions and the isolation of T cells specific for self or microbial antigens from the tissues or blood of patients. Animal models have been very useful for elucidating the pathogenesis of these disorders.

Was this article helpful?

0 0
How To Bolster Your Immune System

How To Bolster Your Immune System

All Natural Immune Boosters Proven To Fight Infection, Disease And More. Discover A Natural, Safe Effective Way To Boost Your Immune System Using Ingredients From Your Kitchen Cupboard. The only common sense, no holds barred guide to hit the market today no gimmicks, no pills, just old fashioned common sense remedies to cure colds, influenza, viral infections and more.

Get My Free Audio Book

Post a comment