Montero Ruth, Chan Justin Tze Ho, Müller Claudia, Just Philip Niclas, Ostermann Sven, Øverland Margareth, Maisey Kevin, Korytář Tomáš, Köllner Bernd
Laboratory for Comparative Immunology, Friedrich-Loeffler-Institut, Federal Research Institute for Animal Health, Institute of Immunology, Südufer 10, 17493 Greifswald-Insel Riems, Germany.
Institute of Parasitology, Biology Centre of the Czech Academy of Sciences, 37005 Czech Budejovice, Czech Republic.
Biology (Basel). 2022 Jan 21;11(2):174. doi: 10.3390/biology11020174.
In poikilothermic vertebrates, seasonality influences different immunological parameters such as leukocyte numbers, phagocytic activity, and antibody titers. This phenomenon has been described in different teleost species, with immunological parameters peaking during warmer months and decreased levels during winter. In this study, the cellular immune responses of rainbow trout kept under constant photoperiod and water temperature against intraperitoneally injected during the summer and winter were investigated. The kinetics of different leukocyte subpopulations from peritoneal cavity, spleen, and head kidney in response to the bacteria was measured by flow cytometry. Furthermore, the kinetics of induced -specific antibodies was evaluated by ELISA. Despite maintaining the photoperiod and water temperature as constant, different cell baselines were detected in all organs analyzed. During the winter months, B- and T-cell responses were decreased, contrary to what was observed during summer months. However, the specific antibody titers were similar between the two seasons. Natural antibodies, however, were greatly increased 12 h post-injection only during the wintertime. Altogether, our results suggest a bias toward innate immune responses and potential lymphoid immunosuppression in the wintertime in trout. These seasonal differences, despite photoperiod and water temperature being kept constant, suggest an internal inter-seasonal or circannual clock controlling the immune system and physiology of this teleost fish.
在变温脊椎动物中，季节性会影响不同的免疫参数，如白细胞数量、吞噬活性和抗体滴度。这种现象在不同的硬骨鱼物种中都有描述，免疫参数在温暖月份达到峰值，在冬季则下降。在本研究中，调查了在恒定光周期和水温条件下饲养的虹鳟鱼在夏季和冬季对腹腔注射的细胞免疫反应。通过流式细胞术测量腹腔、脾脏和头肾中不同白细胞亚群对细菌反应的动力学。此外，通过酶联免疫吸附测定法评估诱导特异性抗体的动力学。尽管光周期和水温保持恒定，但在所有分析的器官中都检测到了不同的细胞基线。在冬季，B细胞和T细胞反应下降，这与夏季观察到的情况相反。然而，两个季节的特异性抗体滴度相似。然而，仅在冬季，天然抗体在注射后12小时大幅增加。总之，我们的结果表明，虹鳟鱼在冬季偏向于先天性免疫反应，并且可能存在淋巴细胞免疫抑制。尽管光周期和水温保持恒定，但这些季节性差异表明存在一个内部的季节间或年周期时钟，控制着这种硬骨鱼的免疫系统和生理机能。
