Kinetics of T lymphocyte subsets and B lymphocytes in response to immunostimulants in flounder (Paralichthys olivaceus): implications for CD4+ T lymphocyte differentiation

• Published in: Scientific reports 2020-08, Vol.10 (1), p.13827-13827, Article 13827
• Main Authors: Xing, Jing, Tian, Hong-fei, Tang, Xiao-qian, Sheng, Xiu-zhen, Zhan, Wen-bin
• Format: Article
• Language: English
• Subjects: 631/250; 631/80; Animals; B-Lymphocytes - immunology; beta-Glucans - immunology; CD4 antigen; CD4-Positive T-Lymphocytes - immunology; CD8 antigen; CD8-Positive T-Lymphocytes - immunology; Cytokines; Cytokines - metabolism; Flounder - immunology; Helper cells; Humanities and Social Sciences; Immune system; Immunoglobulin M; Immunoglobulin M - immunology; Immunostimulants; Lymphocytes; Lymphocytes B; Lymphocytes T; Monoclonal antibodies; multidisciplinary; Paralichthys olivaceus; Poly I-C - immunology; Polyinosinic:polycytidylic acid; Science; Science (multidisciplinary); Stimulants; Th1 Cells; Th17 Cells; Th2 Cells; Transcription factors; Transcription Factors - metabolism; β-Glucan
• ISSN: 2045-2322; 2045-2322
• DOI: 10.1038/s41598-020-69542-6

CD4 + T lymphocytes play crucial roles in the adaptive immune system. CD4, as the most effective marker to delineate the T-helper subsets, was identified in many fish species. Two CD4 homologs, CD4-1 and CD4-2, have been reported in flounder ( Paralichthys olivaceus ). In this study, monoclonal antibodies (mAbs) against CD4-1 and CD4-2 of flounder were produced, CD4 + T lymphocytes were isolated and identified, and the variations in CD4 + and CD8 + T lymphocytes and IgM + B lymphocytes after Poly I:C, PMA or β-glucan stimulation were investigated. Then, the expression of transcription factors and cytokines in sorted CD4 + T lymphocytes was analyzed. The results showed that the mAbs were specific to flounder CD4-1 + and CD4-2 + T cells. CD4-1 + and CD4-2 + cells responded to all three stimulants, while CD8 + T lymphocytes only give a strong response to Poly I:C, and the percentages of IgM + B lymphocytes showed a tendency to increase. After stimulation, the expression of transcription factors and cytokines of Th1, Th2 and Th17 cells varied in CD4 + T cells. These results will provide crucial foundations for the differentiation and function of teleost CD4 + T lymphocytes.