Development of monoclonal antibodies for analyzing immune and hematopoietic systems of common marmoset

Objective Common marmosets are considered experimental animals of primates useful for medical research. We developed several monoclonal antibodies (mAbs) directed to CD molecules to gain initial insight into the immune and hematopoietic systems of this organism, and analyzed the basic cellularity and characters of marmoset lymphocytes. Materials and Methods Anti-marmoset CD antigen mAbs were prepared using marmoset antigen-expressing transfectants and used for flow cytometric analyses and cell fractionation. Expression of T-cell−related cytokine gene transcripts was examined in response to T-cell receptor stimulation by reverse transcription polymerase chain reaction analyses. Hematopoietic progenitor activities of marmoset bone marrow cells were examined in fractionated cells by mAbs against CD117 (c-kit) and CD34. Results CD4 and CD8 expression profiles in T-cell subsets of marmoset were essentially similar to those in mouse and human. CD4+ and CD8+ subsets were isolated from marmoset spleens. Detected transcripts after stimulation of T cells included Th1-, Th2-, and Th17-related cytokines in CD4+ cells and cytotoxic proteases in CD8+ cells, respectively. Colony-forming abilities were detected mainly in CD117 (c-kit)+ cells, irrespective of CD34 expression. Conclusions Marmoset immune system was basically similar to human and mouse systems.