Question

Which of the following statements regarding T-cell receptors recognition of antigen is correct?

A. T-cell receptors recognize antigen only as a peptide bound to an MHC molecule
B. T-cell receptors recognize antigens in their naive form
C. T-cell receptors, like B cell Ig, can recognize carbohydrate, lipid and protein antigen
D. Antigen processing occurs in extracellular spaces

Answer 1

The correct statement is that T-cell receptors recognize antigens only as a peptide bound to an MHC molecule.

Step-by-step explanation:

The correct statement regarding T-cell receptors recognition of antigen is: A. T-cell receptors recognize antigen only as a peptide bound to an MHC molecule.

T cells do not recognize self-antigens directly, but only processed antigens that are presented on the surface of specialized cells called antigen-presenting cells. These processed antigens are bound to major histocompatibility complex (MHC) molecules. The association of the antigen fragments with an MHC molecule on the surface of a cell is known as antigen presentation, and it allows T-cell receptors to recognize the antigen. T-cell receptors cannot recognize antigens in their naïve form or recognize carbohydrate, lipid, and protein antigens like B-cell immunoglobulins (Ig).