Reyes-Becerril Martha, Guluarte Crystal, Ceballos-Francisco Diana, Angulo Carlos, Esteban M Ángeles
Immunology & Vaccinology Group, Centro de Investigaciones Biológicas del Noroeste (CIBNOR), Instituto Politécnico Nacional 195, Playa Palo de Santa Rita Sur, La Paz, B.C.S. 23090, Mexico.
Fish Innate Immune System Group, Department of Cell Biology & Histology, Faculty of Biology, Regional Campus of International Excellence "Campus Mare Nostrum", University of Murcia, Spain.
Fish Shellfish Immunol. 2017 Jan;60:205-218. doi: 10.1016/j.fsi.2016.11.053. Epub 2016 Nov 25.
In an attempt to control the proliferation of the pathogenic bacterium Vibrio parahaemolyticus in gilthead seabream (Sparus aurata), the immunostimulant effect of lysate and ToxA from this bacterium was evaluated. Fish were intraperitoneally injected twice (first injection, day 1 of the experiment; second injection, day 7) and sampled after one week (on days 8 and 15). Afterwards, all fish specimens were experimentally infected with V. parahaemolyticus and mortality was recovered for 1 week. Fish injected with lysate, ToxA and phosphate buffer saline (control) showed 100%, 50% and 0% survival, respectively, when challenged with the pathogen. Skin mucus immune parameters and immune-related gene expression in skin and spleen were also evaluated. The results showed that mucus immune parameters were enhanced in the lysate and ToxA groups compared with the values obtained for fish from the control group. Expression of IL-1β, TNF-α, C3 and IgM genes was significantly up-regulated in the lysate and ToxA groups, principally after infection with the bacterium. Interestingly, TLR5 gene expression increased in fish immunized with lysate. The most prominent histological characteristic in gut from infected fish was the presence of a great number of intraepithelial leucocytes as well as inflammation of the submucosa, while severe hydropic degeneration and hemosiderosis were detected in liver from infected fish. Injection of lysate or ToxA had a protective effect against the deleterious consequences of subsequent infection with V. parahaemolyticus in gut and liver. The findings underline the potential of lysate and ToxA as potent preventive antigens against this kind of vibriosis.
为了控制致病性副溶血性弧菌在金头鲷（Sparus aurata）中的增殖，评估了该细菌的裂解物和ToxA的免疫刺激作用。鱼腹腔注射两次（第一次注射，实验第1天；第二次注射，第7天），并在一周后（第8天和第15天）取样。之后，所有鱼标本都用副溶血性弧菌进行实验性感染，并记录1周的死亡率。用裂解物、ToxA和磷酸盐缓冲盐水（对照）注射的鱼在受到病原体攻击时，存活率分别为100%、50%和0%。还评估了皮肤黏液免疫参数以及皮肤和脾脏中免疫相关基因的表达。结果表明，与对照组鱼的值相比，裂解物组和ToxA组的黏液免疫参数有所增强。IL-1β、TNF-α、C3和IgM基因的表达在裂解物组和ToxA组中显著上调，主要是在感染细菌后。有趣的是，用裂解物免疫的鱼中TLR5基因表达增加。受感染鱼肠道最显著的组织学特征是存在大量上皮内白细胞以及黏膜下层炎症，而在受感染鱼的肝脏中检测到严重的水样变性和含铁血黄素沉着。注射裂解物或ToxA对随后副溶血性弧菌感染在肠道和肝脏中产生的有害后果具有保护作用。这些发现强调了裂解物和ToxA作为针对这种弧菌病的有效预防性抗原的潜力。
