人类外周血单核细胞(HPMφ)是重要的抗原提呈细胞(APC)。APC在行使抗原提呈功能时,以其膜Ia抗原的表达为先决条件之一;但最强有力的APC是树突状细胞(DC)。部分HPMφ在一定条件下也可衍变为类似DC样的细胞。只有既是HLA—DR~+又是HLA—DQ~+的HPMφ才具有抗原提呈能力。人类Ia分子在抗原提呈中的作用是保护外来抗原,有利于T细胞的识别和激活,继而发生增殖反应。 Human peripheral blood mononuclear cells (HPMφ) are important antigen presenting cells (APCs). APC is one of the prerequisites for the expression of its membrane Ia antigen in antigen presenting function; however, the strongest APC is dendritic cell (DC). Some HPMφ under certain conditions can also be transformed into DC-like cells. Only HPMφ, which is both HLA-DR + and HLA-DQ +, has antigen-presenting ability. The role of human Ia molecules in antigen presentation is to protect foreign antigens, which is beneficial to the recognition and activation of T cells, followed by proliferative responses.