Adaptation Physiology, Department of Animal Sciences, Wageningen University & Research, Wageningen, The Netherlands; Animal Breeding and Genomics, Department of Animal Sciences, Wageningen University & Research, Wageningen, The Netherlands.
Adaptation Physiology, Department of Animal Sciences, Wageningen University & Research, Wageningen, The Netherlands.
Vaccine. 2018 Mar 7;36(11):1444-1452. doi: 10.1016/j.vaccine.2018.01.063.
NAb are defined as antigen binding antibodies present without a known previous exposure to this antigen. NAb are suggested to enhance specific antibody (SpAb) responses, but consequences of different NAb levels on immunization are largely unknown. Layer chickens were divergently selected and bred for keyhole limpet hemocyanin (KLH)-binding NAb titers, resulting in a High line and a Low line. In this study, we investigated: (1) the relation of NAb levels with SpAb titers; and (2) the effect of immunization on NAb titers. The 50 highest females of the High line and the 50 lowest females of the Low line of generation 2 were intramuscularly immunized at 33 weeks of age with 1 mL phosphate buffered saline (PBS) containing one of four treatments: (1) negative control (no antigen), (2) 500 µg KLH, (3) 100 µg avian tuberculin purified protein derivative of Mycobacterium avium (PPD), or (4) 250 µg human serum albumin (HuSA). IgM and IgG titers of NAb and SpAb in plasma were determined prior to immunization and weekly for 5 weeks post immunization by indirect ELISA. In addition, antibody affinity was investigated. No differences in SpAb and NAb response against KLH and PPD were observed as a consequence of different NAb titers, but increased and prolonged SpAb and NAb titer responses against HuSA were observed for the High line compared to the Low line. Different natural antibody titers did not impair SpAb dynamics and SpAb affinity. NAb titers were not, or for only short-term, affected by immunization. We show here that NAb may enhance SpAb responses, but that this effect is antigen-dependent. We hypothesize that NAb play a role in general disease resistance through enhancement of the humoral adaptive immune response.
NAb 被定义为在没有已知先前暴露于该抗原的情况下存在的抗原结合抗体。NAb 被认为可以增强特异性抗体（SpAb）反应，但不同 NAb 水平对免疫接种的后果在很大程度上尚不清楚。层鸡被进行了关键孔贻贝血蓝蛋白（KLH）结合 NAb 滴度的差异选择和繁殖，从而产生了高线和低线。在这项研究中，我们研究了：（1）NAb 水平与 SpAb 滴度的关系；（2）免疫接种对 NAb 滴度的影响。第 2 代的高线的前 50 只最高雌性和低线的前 50 只最低雌性在 33 周龄时肌肉内注射 1 毫升磷酸盐缓冲盐水（PBS），其中含有以下四种处理之一：（1）阴性对照（无抗原），（2）500μg KLH，（3）100μg禽结核菌素纯化蛋白衍生物（PPD），或（4）250μg人血清白蛋白（HuSA）。在免疫接种前和免疫接种后每周通过间接 ELISA 测定血浆中 NAb 和 SpAb 的 IgM 和 IgG 滴度，共 5 周。此外，还研究了抗体亲和力。不同的 NAb 滴度不会导致针对 KLH 和 PPD 的 SpAb 和 NAb 反应的差异，但与低线相比，高线对 HuSA 的 SpAb 和 NAb 滴度反应增加且延长。不同的天然抗体滴度不会损害 SpAb 动力学和 SpAb 亲和力。NAb 滴度不受免疫接种的影响，或者仅短期受到影响。我们在这里表明，NAb 可能增强 SpAb 反应，但这种作用是抗原依赖性的。我们假设 NAb 通过增强体液适应性免疫反应在一般疾病抵抗中发挥作用。
