The Biological Significance of Cellular Alloantigen Systems in Captive Avian Populations

本研究的总体目标是应用已获得的家禽免疫遗传学知识来保护圈养鸟类的遗传健康，特别是那些濒临灭绝的鸟类。在鸡中，有12个基因位点或基因复合物产生红细胞抗原，最近在本实验室发现了另外5个决定淋巴细胞特异性的基因位点。这些多态基因的遗传系统在几个方面具有潜在的益处。有些基因系统具有明显的生理作用。B系统是鸡的主要组织相容性复合体（MHC），在体液和细胞免疫应答中都具有重要意义。B系统是多基因复合体的一个例子，其中遗传了两种不同的B基因复合体的个体由于更有效的免疫防御而处于生存优势。其他高度多态的系统将被检查在暴露于自然发生的疾病下对生存的具体影响。已知编码淋巴细胞抗原的其他系统在对环境刺激的整体免疫反应中与MHC相互作用。为特定免疫遗传学目标而开发的独特遗传资源和试剂使与相关领域的同事进行跨学科研究成为可能——限制性片段长度多态性、对环境疾病生物体的天然抗性、基因组作图以及使用同种异体抗原基因系统作为监测个体适应性的标记。最后，随着时间的推移，对鸟类种群中这些多基因系统的研究将增强我们对它们在鸟类进化中的功能的理解。本研究将应用从鸡的研究中获得的免疫遗传学知识来开发目前数量有限的几种野生鸟类的免疫识别系统的新知识。这将通过在红细胞和白细胞表面识别参与免疫识别的特定分子家族来完成。能够识别圈养鸟类的免疫识别系统的一个直接的实际好处是，它们可以用于简单的血液测试来检查谱系信息，以避免近亲个体的意外交配，从而最大限度地提高小种群的遗传多样性。这些信息将有助于我们保护圈养鸟类的遗传健康，特别是那些濒临灭绝的鸟类。

The overall objective of this research is to apply immunogenetic knowledge already acquired in the domestic fowl toward preserving the genetic health of captive avian species, especially those in danger of extinction. In the chicken there are 12 genetic loci or gene complexes producing antigens on erythrocytes and, more recently some five additional loci determining lymphocyte specificity have been discovered in this laboratory. These genetic systems of polymorphic genes are potentially beneficial in several respects. Some of the gene systems have distinct physiological effects. The B system is the major histocompatibility complex (MHC) of the chicken and is of prime significance in both humoral and cellular immune response. The B system serves as an example of a multi-gene complex in which individuals inheriting two different B gene complexes are at a survival advantage because of more effective immune defense. The other more highly polymorphic systems are to be examined for specific effects on survival under exposure to naturally occurring diseases. Other systems encoding lymphocyte antigens are known to interact with the MHC in the overall immune response to environmental stimuli. The unique genetic stocks and reagents developed for specific immunogenetic objectives make possible interdisciplinary research with colleagues in related areas--restriction fragment length polymorphisms, natural resistance to environmental disease organisms, genome mapping, and the use of alloantigen gene systems as markers in monitoring individual fitness. Finally, studying these multigene systems in avian populations over time will enhance our understanding of their function in the evolution of birds. This research will apply immunogenetic knowledge obtained from study of chickens to develop new knowledge of the immunological recognition systems of several wild bird species which currently exist in very limited numbers. This will be done by identifying, on the surfaces of red and white blood cells, specific families of molecules involved in immune recognition. An immediate practical benefit of being able to identify the immunological recognition systems in captive bird species is their use in a simple blood test to check pedigree information to avoid accidental mating of closely related individuals, and thus to maximize the genetic diversity of small populations. This information will contribute to our ability to preserve the genetic health of captive bird species, especially those in danger of extinction.