Siqueira M, Bandieri A, Reis M S, Sant'anna O A, Biozzi G
Eur J Immunol. 1976 Apr;6(4):241-9. doi: 10.1002/eji.1830060403.
Selective breeding has been performed in mice for their high or low antibody responsiveness to Salmonella antigens (Ag). Two noncross-reacting Salmonellae (S. typhimurium and S. oranienburg) have been alternately used to immunize successive generations in order to avoid interference of maternally transmitted antibody. Both Salmonellae carry two independent antigens: flagellar (f) and somatic (s). Two two-way selections were carried out: one for agglutinin response to fAg and the other for agglutinin response to sAg (Selection Ags). The agglutinin response to the other independent Ag was also measured (Associated Ags). The phenotypic character chosen for selection is the maximal agglutinin titer in response to optimal immunization. In both selections, high and low responder lines diverged progressively. There was a 27-fold interline difference in the F13 generation of selection for fAg response and a 38-fold one in the F11 generation of selection for sAg response. This divergence and the continuous distribution of phenotypes in the foundation population indicate that the quantitative character investigated is subject to polygenic regulation. The realized heritability (h2) of the character, measured from the interline divergence, was 0.18 +/- 0.06 in both f and s selections. This means that about 20% of the phenotypic variance of the foundation population is additive. The modification of immune responsiveness to the selection Ag produced by selective breeding was accompanied by a parallel and equivalent effect on immune responsiveness to the noncross-reacting Associated Ag. This effect is therefore entirely nonspecific. A small but definite sex effect in favor of female antibody responsiveness was demonstrated. The results are discussed in comparison with other selection experiments made in mice for quantitative antibody response to other antigens.
人们已经对小鼠进行了选择性育种，以培育出对沙门氏菌抗原（Ag）具有高或低抗体反应性的品系。交替使用两种无交叉反应的沙门氏菌（鼠伤寒沙门氏菌和奥兰延堡沙门氏菌）对连续几代小鼠进行免疫，以避免母源传递抗体的干扰。这两种沙门氏菌都携带两种独立的抗原：鞭毛抗原（f）和菌体抗原（s）。进行了两项双向选择：一项是针对对f抗原的凝集素反应，另一项是针对对s抗原的凝集素反应（选择抗原）。还测量了对另一种独立抗原的凝集素反应（相关抗原）。选择所依据的表型特征是对最佳免疫反应的最大凝集素滴度。在这两项选择中，高反应品系和低反应品系逐渐分化。在针对f抗原反应的选择中，F13代品系间差异为27倍；在针对s抗原反应的选择中，F11代品系间差异为38倍。这种分化以及基础群体中表型的连续分布表明，所研究的数量性状受多基因调控。根据品系间差异测得的该性状的实现遗传力（h2）在f和s选择中均为0.18±0.06。这意味着基础群体中约20%的表型变异是可加性的。通过选择性育种对选择抗原产生的免疫反应性的改变，伴随着对无交叉反应的相关抗原的免疫反应性产生平行且等效的效应。因此，这种效应完全是非特异性的。还证明了存在一个小但确定的性别效应，有利于雌性的抗体反应性。将这些结果与在小鼠中针对对其他抗原的定量抗体反应所进行的其他选择实验进行了比较讨论。
