Can T cell selection go wrong?

Yes, T cell selection can go wrong, and when it does, it can lead to serious immune-related disorders. T cell selection is a critical process in which immature T cells called thymocytes undergo a series of tests to ensure their functionality and specificity before they are released into the periphery to participate in the immune response.

When positive selection goes wrong, some T cells might not be able to recognize foreign invaders effectively. This can weaken the immune response, making the body more susceptible to infections and diseases.

When negative selection goes wrong, some T cells escape detection, resulting in the development of autoreactive T cells that recognize their own body as foreign. Under the right conditions such as genetic predisposition or environmental factors, these self-reactive T cells could mistakenly target and damage healthy tissues, leading to autoimmune diseases such as rheumatoid arthritis, multiple sclerosis, or Type 1 diabetes.

Both types of selection errors can disrupt the balance of the immune system, either by weakening its ability to fight infections or by causing it to attack its own tissues. Proper T cell selection is crucial for maintaining a healthy and efficient immune system.