Institute of Immunology of Vilnius University, Moletu pl. 29, LT-2021 Vilnius, Lithuania.
Int Immunol. 2010 Jan;22(1):25-34. doi: 10.1093/intimm/dxp109. Epub 2009 Nov 27.
Melatonin is a hormone that has immunomodulatory activity and is believed to influence the production of antibodies in mammals. The aim of the present study was to investigate the effect of suppressed melatonin synthesis on the antibody production. BALB/c mice were immunized with T-cell-dependent (TD) and T-cell-independent (TI) antigens and kept under (i) normal lighting, (ii) constant exposure to light, (iii) exposed to light and treated daily with melatonin. It was revealed that melatonin modulated TD and TI antibody production. Suppressed melatonin synthesis increased the amount of IgM, IgG1, IgG2b and IgG3 antibodies after immunization with TI antigen. The level of TD antibodies IgM, IgG2a, IgG2b and IgG3 also increased, however, the antigen-specific antibodies of IgG1 isotype significantly decreased in mice exposed to light. Daily melatonin treatment brought the antibody level back to normal. The antibody concentration in the sera of mice kept at normal lighting was significantly higher when the immunizations were performed in the evening. The action of melatonin on B cells via MT2 receptor was shown in vitro and in vivo.
褪黑素是一种具有免疫调节活性的激素，被认为会影响哺乳动物抗体的产生。本研究旨在探讨抑制褪黑素合成对抗体产生的影响。BALB/c 小鼠用 T 细胞依赖性（TD）和 T 细胞非依赖性（TI）抗原免疫，并在以下条件下饲养：（i）正常光照，（ii）持续光照，（iii）光照并每天用褪黑素处理。结果表明，褪黑素调节 TD 和 TI 抗体的产生。用 TI 抗原免疫后，抑制褪黑素合成会增加 IgM、IgG1、IgG2b 和 IgG3 抗体的量。TD 抗体 IgM、IgG2a、IgG2b 和 IgG3 的水平也有所增加，但在光照下的小鼠中，抗原特异性 IgG1 同种型抗体显著减少。每天给予褪黑素治疗可使抗体水平恢复正常。在晚上进行免疫时，在正常光照下饲养的小鼠血清中的抗体浓度明显更高。体外和体内实验均表明褪黑素通过 MT2 受体对 B 细胞发挥作用。
