Tortorella C, Schulze-Koops H, Thomas R, Splawski J B, Davis L S, Picker L J, Lipsky P E
Harold C. Simmons Arthritis Research Center, University of Texas Southwestern Medical Center at Dallas 75235, USA.
J Immunol. 1995 Jul 1;155(1):149-62.
The capacity of four subsets of CD4+ memory T cells, defined by expression of CD45RB and CD27, to provide help for B cells was examined. Larger amounts of Ig were induced by CD45RBdimCD27- cells compared with the CD45RBdimCD27+ population, whereas CD45RBbrightCD27+ or CD27- cells were poor inducers of Ig synthesis. Mitomycin C treatment, which prevents suppressive activity, markedly enhanced Ig production supported by each subset except for CD45RBbrightCD27- cells. Mitomycin C-treated CD45RBdim cells remained the most efficient inducers of Ig production, but no difference was detected between CD27+ and CD27- cells. The subsets also differed in their ability to proliferate and secrete cytokines, but these differences did not explain variations in the capacity to provide help for B cells. Both CD27- subsets exhibited decreased proliferation and uniquely secreted IL-4, with the CD45RBdimCD27- subset producing the greatest quantities of IL-4. No differences in IL-2 and IFN-gamma production were found. IL-10 secretion increased with the acquisition of the CD45RBdim phenotype and, within the CD45RBdim cells, with the loss of CD27. Staining for cytoplasmic cytokines indicated that individual populations of CD27-CD4+ helper T cells produced either IL-4 or IFN-gamma, whereas more than half of the IL-4 producers also synthesized IL-2. Finally, the different abilities of CD4+ memory T cell subsets to support B cell differentiation did not relate to variations in the expression of CD40 ligand. These results indicate that within the CD4+ memory T cell population an increase of helper activity associates with the shift from a CD45RBbright to a CD45RBdim phenotype. Within the CD45RBdim subset, the loss of CD27 is associated with a reduction of suppressive activity.
研究了通过CD45RB和CD27表达定义的CD4 +记忆T细胞的四个亚群为B细胞提供辅助的能力。与CD45RBdimCD27 +群体相比，CD45RBdimCD27-细胞诱导产生的Ig量更多，而CD45RBbrightCD27 +或CD27-细胞诱导Ig合成的能力较差。丝裂霉素C处理可防止抑制活性，除CD45RBbrightCD27-细胞外，显著增强了每个亚群支持的Ig产生。经丝裂霉素C处理的CD45RBdim细胞仍然是诱导Ig产生最有效的细胞，但CD27 +和CD27-细胞之间未检测到差异。这些亚群在增殖和分泌细胞因子的能力上也有所不同，但这些差异并不能解释为B细胞提供辅助能力的变化。两个CD27-亚群均表现出增殖减少并独特地分泌IL-4，其中CD45RBdimCD27-亚群产生的IL-4量最大。未发现IL-2和IFN-γ产生的差异。IL-10分泌随着CD45RBdim表型的获得而增加，在CD45RBdim细胞内，随着CD27的丧失而增加。细胞质细胞因子染色表明，CD27-CD4 +辅助性T细胞的各个群体产生IL-4或IFN-γ，而超过一半的IL-4产生者也合成IL-2。最后，CD4 +记忆T细胞亚群支持B细胞分化的不同能力与CD40配体表达的变化无关。这些结果表明，在CD4 +记忆T细胞群体中，辅助活性的增加与从CD45RBbright表型向CD45RBdim表型的转变相关。在CD45RBdim亚群中，CD27的丧失与抑制活性的降低相关。
