猪出生后IgG重链基因多样性的比较

Comparison of IgG Heavy Chain Gene Diversity in Postnatal Pigs

为研究在正常饲养环境下,猪对体外病原体和疫苗的免疫反应,分析了新生仔猪(0 d)、断奶仔猪(35 d)和成年猪(80 d)抗体重链基因(IGH)的多样性。结果表明:不同发育阶段猪抗体谱的分布有明显差异,成年猪抗体重链可变区(IGHV)1-6的使用频率急剧下降。在3个发育阶段,猪抗体重链多样性的区域(IGHD)阅读框(RF)主要是RFⅢ,其编码亲水性氨基酸。随着个体发育,RFⅢ的使用频率逐渐减少;同时RFⅡ的使用频率不断增加,其编码疏水性氨基酸。末端脱氧核苷酸转移酶(Tdt)的表达水平增加。成年猪的N1区和N2区核酸长差异显著提高。

To explore the immune responses of pigs to pathogens and vaccination in normal situation,we analyzed the antibody heavy chain genes（ IGH） repertoire of the pre-suckle neonate（ 0 d）,wean piglet（ 35 d） and growing pig（ 80 d）. The results show that there are obvious differences in the distribution of antibody profiles at different developmental stages of pigs,and the utilization of Antibody Heavy Chain Variable region（ IGHV） 1-6 dramatically decreases in growing pigs. At all stages,the Antibody Heavy Chain Diversity region（ IGHD） reading frame（ RF） is dominated by RFⅢ,which codes hydrophilic amino acids. With the ontogeny,the RFⅢ use is gradually decreasing;the utilization of RFⅡ of IGHD region is steadily increasing,which codes hydrophobic amino acids.The expression level of Terminal Deoxynucleotidyl Transferase（ Tdt） increases. The nuclein length difference of the N1 and N2 region of growing pigs obviously increases. These results provide a basis for assessing the diversity of pig IGH under normal feeding conditions,which could be used to assess the development of individual immune systems and the evaluation of vaccine immunization procedures in pigs.