Characteristics and immune mechanisms of CD71+ CD235a+ nucleated erythroid cells in elderly / 中华老年医学杂志

ABSTRACT

Objective To explore the immune property and possible mechanism of the CD71+ CD235a+ nucleated erythroid cells from peripheral blood in elderly,as compared with those of healthy young.Methods Peripheral blood obtained by venipuncture from healthy young(n=59,mean age=28 years) and elderly(n=78,mean age=68 years)donors were measured by flow cytometry to evaluate the frequency of the CD71+ CD235a+ cells in peripheral blood mononuclear cells (PBMC).In vitro assays,CD71+ CD235a+ cells were sorted by flow cytometry and T cells were sorted using CD4+T cell isolation kit,then the T cell proliferation assays were conducted by following groupsT cell + CFSE group;T cell +CFSE co-cultured with CD71+ CD235a+ cells from the young donors;T cell + CFSE co-cultured with CD71+ CD235a+ cells from the older donors.Real-time PCR were used to identify the expression of the immune cytokine secreted by CD71+ CD235a+ cells.Results (1)the results showed a significant increase in the percentage of CD71+ CD235a+ cells in the elderly compared with the young [(9.93± 2.95)％ vs (1.96 ± 1.16)％,t =3.37,P ＜ 0.001];(2)the CD71+ CD235a+ cells from the older donors could suppress the proliferation of the T cells (t =2.91,P＜ 0.05)while from the young group we could not observe this phenomenon(t =0.387,P＞0.05).(3)The results of Real-time PCR revealed that,compared with CD71+ CD235a+ cells from the young,CD71+ CD235a+ cells from the elderly expressed higher levels of Arg-2 (t =9.04,P＜0.01),IL-1β,IL-6 and TGF-β(t =4.51,5.46,6.92,all P＜0.05).Conclusions There are higher frequencies of CD71+ CD235a+ cells in aged samples than the young.And the CD71+CD235a cells from the elderly could secrete more Arg-2,IL-1β,IL-6 and TGF-β to suppress the T cell proliferation.