Gregorich Jenna L, Lilburn Michael S, Shanmugasundaram Revathi
Department of Animal Sciences, The Ohio State University, Wooster, OH, United States.
U.S National Poultry Research Center, Athens, GA, United States.
Front Physiol. 2022 Mar 7;13:820349. doi: 10.3389/fphys.2022.820349. eCollection 2022.
Two experiments were conducted to investigate the effects of induced moisture loss on embryonic development and the immune response following an inflammatory challenge immediately post-hatch. In Experiment I, fertile leghorn eggs ( = 100) and commercial broiler eggs ( = 300) were set at 37.5°C and moisture loss was induced in one-half of the Leghorn and broiler eggs by drilling two, 1.5 mm diameter holes. The Control eggs had 0 holes. At embryonic day (ED)18, layer and broiler eggs in the 2-holes treatment had a significant ( < 0.01) increase in moisture loss compared to the control treatment (10.1% vs. 8.2%). Similarly, at ED18, the broiler eggs with 2-holes had a significant increase ( < 0.01) in moisture loss compared with control eggs (9.9% vs. 8.4%). Thymocytes from both the leghorn (104%) and broiler (62%) embryos in the 2-holes treatment had significantly increased proliferation compared with the control embryos ( ≤ 0.05). At ED18, layer and broiler embryos in the 2-holes treatment had an approximate twofold increase in the splenic CD8/CD4 ratio ( ≤ 0.05) and CD4CD25 cells percentage in both the thymus and spleen ( ≤ 0.05). At ED18, both layer and broiler embryos from the 2-holes treatment had a significant increase in splenic IL1-β, IL-6, IL-10, and TLR-4 mRNA transcription compared to the control group ( ≤ 0.05). Experiment II was repeated with 300 fertile broiler eggs. On the day of hatch, chicks were randomly distributed into one of four treatments in a 2 (0, 2 holes) × 2 (0, 500 μg lipopolysaccharide, LPS) factorial arrangement of treatments. Chicks in the LPS groups were injected intraperitoneally with 500 μg/kg BW LPS. At 24 and 48 h post-hatch, chicks hatched from eggs with 2-holes and challenged with LPS had a significant increase ( ≤ 0.05) in thymocyte proliferation at 24 h (42%) and 48 h (37%) when compared with chicks hatched from the control (0-hole; 0 μg LPS) treatment. Chicks hatched from the 2-holes treatment and challenged with the LPS had an approximately twofold higher splenic CD8/CD4 ratio and 1.5 fold increase in CD4CD25 percentage compared to control chicks (P ≤ 0.05). In chicks hatched from the 2-holes treatment, MUC2 mRNA transcription was comparable to control chicks at 24 and 48 h in response to the LPS challenge. Our data suggest that the 2-holes treatment reprograms gene transcription to facilitate cell survival via proliferation and differentiation during an LPS inflammatory challenge.
进行了两项实验,以研究孵化后立即诱导水分流失对胚胎发育以及炎症刺激后免疫反应的影响。在实验I中,将100枚来航种蛋和300枚商品肉种蛋置于37.5°C环境下,在一半的来航种蛋和肉种蛋上钻两个直径1.5毫米的孔,以诱导水分流失。对照蛋没有打孔。在胚胎发育第18天(ED18),与对照处理相比,有两个孔处理的蛋鸡和肉鸡种蛋的水分流失显著增加(P<0.01)(分别为10.1%对8.2%)。同样,在ED18时,有两个孔的肉种蛋与对照蛋相比,水分流失显著增加(P<0.01)(分别为9.9%对8.4%)。与对照胚胎相比,有两个孔处理的来航(104%)和肉鸡(62%)胚胎的胸腺细胞增殖显著增加(P≤0.05)。在ED18时,有两个孔处理的蛋鸡和肉鸡胚胎的脾脏CD8/CD4比值增加了约两倍(P≤0.05),胸腺和脾脏中CD4CD25细胞百分比也增加(P≤0.05)。在ED18时,与对照组相比,有两个孔处理的蛋鸡和肉鸡胚胎脾脏中IL1-β、IL-6、IL-10和TLR-4 mRNA转录显著增加(P≤0.05)。实验II使用300枚可育肉种蛋重复进行。在孵化当天,雏鸡被随机分配到四种处理之一,采用2(0个孔,2个孔)×2(0,500微克脂多糖,LPS)析因设计处理。LPS组的雏鸡腹腔注射500微克/千克体重的LPS。在孵化后24小时和48小时,与从对照(0个孔;0微克LPS)处理孵化出的雏鸡相比,从有两个孔的蛋孵化出并接受LPS刺激的雏鸡在24小时(42%)和48小时(37%)时胸腺细胞增殖显著增加(P≤0.05)。与对照雏鸡相比,从有两个孔的处理孵化出并接受LPS刺激的雏鸡脾脏CD8/CD4比值大约高出两倍,CD4CD25百分比增加了1.5倍(P≤0.05)。在从有两个孔的处理孵化出的雏鸡中,在24小时和48小时对LPS刺激的反应中,MUC2 mRNA转录与对照雏鸡相当。我们的数据表明,有两个孔的处理可重编程基因转录,以在LPS炎症刺激期间通过增殖和分化促进细胞存活。