Effects of pre-existing antibody on seroconversion rate after influenza vaccination / 中华微生物学和免疫学杂志

Objective:To investigate the effects of pre-existing antibody on seroconversion rate after influenza vaccination.Methods:This study recruited 1 900 healthy volunteers to receive influenza split vaccines in Xinjiang Uygur Autonomous region and Yunnan Province from September 2009 to October 2018. Hemagglutinin agglutination inhibition assay was used to detect the titers of specific antibodies in blood samples collected before vaccination and 28 d after vaccination and the effects of pre-existing antibody on the seroconversion to different influenza vaccine components were analyzed.Results:Trend analysis showed that with the increasing titer of pre-existing antibody, the seroconversion rates to A/H1N1, A/H3N2, B/Victoria and B/Yamagata vaccine components were gradually decreased (χ 2=121.76, P<0.001; χ 2=67.58, P<0.001; χ 2=45.25, P<0.001; χ 2=54.55, P<0.001). After adjusting for factors such as region, gender and age, multivariate logistic regression showed that pre-existing antibody titer equal to or higher than 40 was an independent factor that affected the seroconversion to A/H1N1, A/H3N2 and B/Victoria vaccine components, and the adjusted OR (95%CI) values were 2.50(2.00-3.13)、1.64(1.35-2.00) and 2.50(1.79-3.45), respectively. Conclusions:The seroconversion rate to each vaccine component was negatively correlated with the pre-existing antibody titer. The factor that pre-existing antibody titer equal to or higher than 40 was detrimental to the seroconversion to A/H1N1, A/H3N2 and B/Victoria vaccine components, but had no significant influence on B/Yamagata seroconversion.

Progress in the role of leptin in immune response / 中华微生物学和免疫学杂志

Leptin, a peptide hormone discovered in the 1990s, arouses interest as it can regulate the body′s metabolism. In recent years, many studies have shown that leptin can promote the proliferation, activation and cytokine synthesis of various immune cells, and participate in innate and adaptive immune responses. This article reviewed the role of leptin and involved signaling pathways in immune response and the potential of leptin as a vaccine adjuvant.