Sturgill Tracy L, Giguère Steeve, Berghaus Londa J, Hurley David J, Hondalus Mary K
Department of Large Animal Medicine, University of Georgia, Athens, GA, United States.
Department of Large Animal Medicine, University of Georgia, Athens, GA, United States.
Vaccine. 2014 Mar 10;32(12):1362-7. doi: 10.1016/j.vaccine.2014.01.032. Epub 2014 Jan 28.
Equine neonates have reduced humoral and cell-mediated immune responses compared to adult horses after administration of killed vaccines. As a basis for this study, we hypothesized that newborn foals can mount strong immune responses after vaccination with live Mycobacterium bovis BCG.
Healthy 4-day-old foals (n=7), 4-month-old foals (n=7) and adult horses (n=6) were vaccinated once with live M. bovis BCG. Age-matched animals (n=5 per group) were used as unvaccinated controls. Relative vaccine-specific immunoglobulin concentrations and whole blood mRNA expression of IFN-γ, IL-4, and IL-10 were measured prior to and 2, 4, 6, and 8 weeks after vaccination. Eight weeks after vaccination, delayed type hypersensitivity (DTH) responses were assessed by measuring the increase in double skin thickness after intradermal injection of purified protein derivative.
Both groups of foals and adult horses responded with a significant increase in vaccine-specific total IgG, IgGa, IgGc, IgG(T), and IgM concentrations. In contrast, only adult horses mounted significant IgGb responses. Vaccine-specific concentrations of total IgG and IgGa were significantly higher in adult horses than in 4-day-old foals whereas IgGc responses were significantly higher in 4-day-old foals than in the other two age groups. Adult horses had significantly higher basal IFN-γ and IL-4 mRNA expression than both groups of foals but vaccination with M. bovis BCG did not significantly increase expression of these cytokines, regardless of age group. Immunized horses had significantly higher DTH responses than age-matched unvaccinated controls. DTH responses were significantly greater in both groups of vaccinated foals than in vaccinated adult horses.
Despite a naïve immune system, newborn foals have the ability to mount robust antibody and cell-mediated immune responses to M. bovis BCG.
与成年马相比，马驹在接种灭活疫苗后体液免疫和细胞介导免疫反应会降低。作为本研究的基础，我们假设新生马驹接种活卡介苗后能够产生强烈的免疫反应。
对7匹健康的4日龄马驹、7匹4月龄马驹和6匹成年马接种一次活卡介苗。将年龄匹配的动物（每组5匹）作为未接种疫苗的对照。在接种疫苗前以及接种后2、4、6和8周，测量相对疫苗特异性免疫球蛋白浓度以及全血中IFN-γ、IL-4和IL-10的mRNA表达。接种疫苗8周后，通过测量皮内注射纯化蛋白衍生物后皮肤双厚度的增加来评估迟发型超敏反应（DTH）。
两组马驹和成年马接种疫苗后疫苗特异性总IgG、IgGa、IgGc、IgG(T)和IgM浓度均显著增加。相比之下，只有成年马产生了显著的IgGb反应。成年马的疫苗特异性总IgG和IgGa浓度显著高于4日龄马驹，而4日龄马驹的IgGc反应显著高于其他两个年龄组。成年马的基础IFN-γ和IL-4 mRNA表达显著高于两组马驹，但接种卡介苗后，无论年龄组如何，这些细胞因子的表达均未显著增加。免疫后的马的DTH反应显著高于年龄匹配的未接种疫苗对照。两组接种疫苗的马驹的DTH反应均显著大于接种疫苗的成年马。
尽管新生马驹的免疫系统幼稚，但它们有能力对卡介苗产生强大的抗体和细胞介导免疫反应。
