Correlation of Tfh cell content in peripheral blood proportion and intracellular IL-21 with retinal damage caused by blue light / 实用医学杂志

ABSTRACT

Objective To investigate the correlation between the proportion of peripheral blood follicular T helper cells(Tfh cells)and intracellular interleukin-21(IL-21)content with blue light retinal injury.Methods Brown Norway(BN)rats were randomly divided into 4 groups and were exposed to blue light for 3 hours a day to establish retinal light damage model.According to the duration of illumination,the rats was divided into 0 days(control group),3 days(3 d group),7 days(7 d group)and 14 days(14 d group).The proportion of Tfh cells and content of IL-21 in Tfh cells in peripheral blood of each group was detected by flow cytometry and ELISA sepa-rately after illumination.Electroretinogram(ERG)was used to evaluate retinal function.The changes of fundus in rats were observed by fundus photography.The thickness of outer nuclear layer of retina was analyzed by HE staining.Results After retinal blue light injury,with the extension of illumination time,the proportion of Tfh cells in peripheral blood and intracellular IL-21 content both increased(P<0.05).ERG showed that retinal function decreased after light damage and aggravated with the extension of illumination time,the latency and ampli-tudes of A-wave and B-wave increased and decreased respectively(P<0.05).The retinal fundus of rats showed depigmentation in 3 d,and the retinal vessels became thinner and exudate with the extension of illumination time.HE staining showed that the outer nuclear layer of retina(ONL)became thinner(P<0.05).Correlation analy-sis indicated that the proportion of Tfh cells in peripheral blood and the intracellular IL-21 content could jointly reflect the degree of injury(P<0.000 1),and the proportion of Tfh cells in peripheral blood was negatively corre-lated with ONL thickness and the amplitude of a and b waves,positively correlated with the peak time of a and b waves,(P<0.0001).Conclusion The proportion of Tfh cells in peripheral blood and the intracellular IL-21 content were increased after blue light damage to retina,and were significantly increased with the extension of light time with a certain correlation.