Thomé Julia, Limmer Julia, Brose Teresa Z, Zeller Johannes, Chevalier Nina, Schäfer Anna-Lena, Schneider Laura, Lind Maike, Christmann Thierry, Dreck Marie, Kreuzaler Sheena, Braig David, Peter Karlheinz, Pankratz Franziska, Eisenhardt Steffen U
Department of Plastic and Hand Surgery, Medical Center and Faculty of Medicine, University of Freiburg, Freiburg, Germany.
Department of Dermatology, Medical Center - University of Freiburg, Freiburg, Germany.
Front Immunol. 2025 Jul 18;16:1622865. doi: 10.3389/fimmu.2025.1622865. eCollection 2025.
T cells are major components of the immune system. Their activation requires interaction between the T cell receptor and co-stimulatory molecules, crucial during infection, inflammation, and allogeneic rejection. Monomeric CRP (mCRP) is a known modulator of inflammation and particularly the innate immune response, however its interaction with T cells as part of the adaptive immune response remains unclear.
Peripheral blood mononuclear cells (PBMC) and T cells were isolated. Flow cytometric analysis was conducted to evaluate Fcγ receptor CD16 expression on T cells, the binding of CRP to T cells, and its impact on proliferation and apoptosis. T cell activation was assessed after 1, 2, 3, 5 and 7 days by assessing CD69 and CD25 expression, and under various conditions including coculture with monocytes and several inhibitory factors.
T cells express CD16 that binds mCRP in a concentration-dependent manner, and particularly on activated T cells. While mCRP reduces apoptosis and accelerates proliferation in T cells, it does not independently activate them. However, activation of monocytes by mCRP leads to T cell activation, indicating a direct cell to cell interaction during CRP-induced activation. This effect could be alleviated by inhibition of the CD80/CD28 pathway.
CRP does not activate T Cells directly but via PI3-kinase-dependent activation of monocytes and subsequent CD80/CD28 cell to cell contact. The findings suggest the effects of CRP on T cells depend on their environment and the presence of other proinflammatory agents.
T细胞是免疫系统的主要组成部分。它们的激活需要T细胞受体与共刺激分子之间的相互作用，这在感染、炎症和同种异体排斥反应中至关重要。单体CRP（mCRP）是一种已知的炎症调节剂，尤其是先天性免疫反应的调节剂，然而，其作为适应性免疫反应一部分与T细胞的相互作用仍不清楚。
分离外周血单核细胞（PBMC）和T细胞。进行流式细胞术分析以评估T细胞上Fcγ受体CD16的表达、CRP与T细胞的结合及其对增殖和凋亡的影响。在1、2、3、5和7天后，通过评估CD69和CD25的表达，并在包括与单核细胞共培养和几种抑制因子在内的各种条件下，评估T细胞的激活情况。
T细胞表达CD16，其以浓度依赖性方式结合mCRP，特别是在活化的T细胞上。虽然mCRP减少T细胞凋亡并加速其增殖，但它不能独立激活它们。然而，mCRP激活单核细胞会导致T细胞激活，表明在CRP诱导的激活过程中存在直接的细胞间相互作用。这种作用可通过抑制CD80/CD28途径来缓解。
CRP不是直接激活T细胞，而是通过PI3激酶依赖性激活单核细胞以及随后的CD80/CD28细胞间接触来激活。这些发现表明CRP对T细胞的影响取决于它们的环境和其他促炎因子的存在。
