Investigation of the humoral immune index levels among Tibetans and Hans in Changdu，Tibet

Abstract:

Objective：To investigate the levels of the humoral immune index among Tibetans and Hans in Changdu，Tibet，and com－pare the differences between the two groups，and that between samples in Tibet and Chongqing. Furthermore，to discuss the establish－ment of local reference intervals. Methods：Serum samples were collected from 392 subjects who underwent physical examination in The Changdu People’s Hospital of Tibet from April to September 2018，including 195 Tibetans and 197 Hans. Serum IgA，IgG，IgM，complement C3 and C4 levels were detected by immune scatter turbidity method，which were compared with the humoral immune index levels of 200 subjects who underwent physical examination in The First Affiliated Hospital of Chongqing Medical University，so as to analyze the differences among different regions，nationalities and genders. Results：The levels of complement C3（Z=-11.900，P=0.000） and IgM（Z=-3.063，P=0.002） in Tibet were higher than those in Chongqing while the level of IgA was lower than that in Chongqing（Z=-4.287，P=0.000） and there were not significant differences in the levels of complement C3 and IgG. In Tibet，the C3 level of the Tibetans was higher than that of the Hans（Z=-2.799，P=0.005），and the rest showed no significant difference. The levels of IgG（t=-3.787，P=0.000） and IgM（Z=-6.736，P=0.000） in female Tibetans were significantly higher than those in the males，and the levels of IgG（Z=-3.817，P=0.000） and IgM（Z=-3.356，P=0.001） in female Hans were also higher than those in male Hans. Addi－tionally，the C3 level in male Tibetans was higher than that in male Hans（Z=-3.489，P=0.000） while the IgM level in male Tibetans was lower than that in male Hans（Z=-2.521，P=0.012）. However，there were no significant differences between Tibetan female popu－lation and Han female population in humoral immune index levels. Conclusion：The humoral immune index levels of Tibetan and Han people in Changdu，Tibet are different from those in Chongqing，and differences between different nationalities and genders are also present. Therefore，specific reference intervals should be established according to the healthy population of each group.