Question

An adhesion molecule called _____ is expressed exclusively on activated dendritic cells and binds to _____ on naive T cells in the T-cell areas of secondary lymphoid tissue.

1) DC-SIGN; ICAM-3
2) CD2; LFA-3
3) MHC class II; T-cell receptor
4) L-selectin; GlyCAM-1
5) ICAM-1; LFA-1

Answer 1

The adhesion molecule expressed exclusively on activated dendritic cells is DC-SIGN, which binds to ICAM-3 on naive T cells, making the correct answer '1) DC-SIGN; ICAM-3.'

Step-by-step explanation:

The adhesion molecule expressed exclusively on activated dendritic cells is DC-SIGN, which binds to ICAM-3 on naive T cells in the T-cell areas of secondary lymphoid tissue. Therefore, the correct answer to the question is 1) DC-SIGN; ICAM-3.

Explanation: Dendritic cells (DCs) play a crucial role in the immune system by presenting antigens to naive T cells and initiating an immune response. They express various cell surface receptors, including DC-SIGN, which is crucial for interacting with naive T cells in secondary lymphoid organs where immune responses are often initiated. Naive T cells express ICAM-3, which binds to DC-SIGN on dendritic cells, thus facilitating the interaction between these two cell types. This binding is essential for the activation of naive T cells by the antigen-presenting dendritic cells, which present antigens in the context of MHC molecules.