Question

Which of the following statements are correct regarding immature thymocytes in a transgenic mice with TCR recognizing self peptide xcv and immunized with peptide xcv.

a. Immature T cells will mature and leave the thymus and will be activated by APC presenting xcv peptide in the secondary lymph nodes.
b. Immature T cells will mature but will tolerate xcv peptide in the periphery
c. Immature T cells will be killed by negative selection in the thymus.
d. Immature T cells will die from apoptosis due to positive selection.
e. Immature T cells will become anergic and will not be activated when the APC present xcv in the periphery

Answer 1

The correct statement about the fate of immature thymocytes in transgenic mice with TCR specific for a self-peptide XCV is that they will be eliminated by negative selection in the thymus to prevent autoimmune responses.

Step-by-step explanation:

The correct statement regarding immature thymocytes in transgenic mice with TCR recognizing self-peptide XCV and immunized with peptide XCV is that immature T cells will be killed by negative selection in the thymus. The process of thymic selection ensures that self-reactive T cells, which recognize self-antigens such as peptide XCV, are eliminated via apoptosis to prevent autoimmune responses. This is a part of the central tolerance mechanism, which serves to prevent the maturation and activation of T cells that could potentially attack the body's own cells.

During negative selection, immature thymocytes that strongly bind self-antigens presented by antigen-presenting cells (APCs) in the thymus are induced to undergo apoptosis. This is to ensure that T cells that might cause autoimmunity are removed before they can leave the thymus and enter the peripheral tissues. Therefore, option c. "Immature T cells will be killed by negative selection in the thymus" is correct regarding the fate of the thymocytes recognizing self-peptide XCV in this scenario.