Colwell D E, Michalek S M, Briles D E, Jirillo E, McGhee J R
J Immunol. 1984 Aug;133(2):950-7.
The present investigation reports the production of monoclonal antibodies to antigenic determinants of the O-polysaccharide of Salmonella typhimurium lipopolysaccharide (LPS), and assesses the effectiveness of these antibodies in protecting C3H mice against the lethal effects of Salmonella infection. Hybridomas were generated by fusing spleen cells from (BALB/c X A/J)F1 (CAF1) mice hyperimmunized by i.v. injection with acetone-killed S. typhimurium SR-11 with X63-Ag8.653 murine myeloma cells. Hybridomas producing antibodies reactive with S. typhimurium SR-11 whole cells were subcloned, and seven of the resulting clones as well as one previously described clone were selected for use in the studies reported here. Monoclonal antibodies from these eight clones were of the IgG1 (1), IgG3 (6), or IgM (1) isotype and were specific for the O-polysaccharide region of Salmonella LPS, reacting with LPS from smooth S. typhimurium SR-11 and LT-2, but not with LPS from rough S. minnesota R60 (Ra), R345 (Rb), or R595 (Re). The effectiveness of each monoclonal antibody in protecting C3H/HeN and C3H/HeJ mice against the lethal effects of Salmonella infection was evaluated by comparing the median length of survival of groups of mice given antibody by i.p. injection before i.p. challenge with virulent S. typhimurium SR-11 to that of animals that received no antibody. Three out of eight monoclonal anti-O-polysaccharide antibodies, ST-1 (IgM), 10-5-47 (IgG3), and 10-5-6 (IgG3), provided significant (p less than 0.01) protection to C3H/HeN mice challenged with approximately 10(4) LD100 of Salmonella. Only antibodies ST-1 and 10-5-6, however, extended the median length of survival of C3H/HeJ mice beyond that of infected controls. Mouse antiserum prepared against S. typhimurium SR-11 was equally protective in C3H/HeJ mice. In an attempt to understand the contribution of antibody specificity to the relative differences in the protective capacities of the monoclonal antibodies, their reactivities with several Salmonella reference strains of different classical serotypes were examined. Although some differences in reactivity against the different strains were apparent, this approach was not adequate for defining the fine specificity of these monoclonal antibodies. The results of this study provide evidence that monoclonal antibodies with specificity to the O-polysaccharide region of Salmonella LPS can protect C3H mice against challenge with the homologous bacterial strain.
本研究报告了针对鼠伤寒沙门氏菌脂多糖（LPS）O-多糖抗原决定簇的单克隆抗体的产生，并评估了这些抗体在保护C3H小鼠免受沙门氏菌感染致死效应方面的有效性。通过将经静脉注射丙酮灭活的鼠伤寒沙门氏菌SR-11超免疫的（BALB/c×A/J）F1（CAF1）小鼠的脾细胞与X63-Ag8.653鼠骨髓瘤细胞融合，产生杂交瘤。产生与鼠伤寒沙门氏菌SR-11全细胞反应的抗体的杂交瘤进行亚克隆，并选择所得克隆中的7个以及先前描述的1个克隆用于本报告的研究。来自这8个克隆的单克隆抗体属于IgG1（1个）、IgG3（6个）或IgM（1个）同种型，对沙门氏菌LPS的O-多糖区域具有特异性，与光滑型鼠伤寒沙门氏菌SR-11和LT-2的LPS反应，但不与粗糙型明尼苏达沙门氏菌R60（Ra）、R345（Rb）或R595（Re）反应。通过比较在腹腔注射强毒鼠伤寒沙门氏菌SR-11进行攻击前经腹腔注射抗体的小鼠组与未接受抗体的动物的中位存活时间，评估每种单克隆抗体在保护C3H/HeN和C3H/HeJ小鼠免受沙门氏菌感染致死效应方面的有效性。8种抗O-多糖单克隆抗体中的3种，即ST-1（IgM）、10-5-47（IgG3）和1十条-5-6（IgG3），对用约10⁴ LD100沙门氏菌攻击的C3H/HeN小鼠提供了显著（p<0.01）的保护。然而，只有抗体ST-1和10-5-6延长了C3H/HeJ小鼠的中位存活时间，超过了感染对照。针对鼠伤寒沙门氏菌SR-11制备的小鼠抗血清在C3H/HeJ小鼠中同样具有保护作用。为了试图理解抗体特异性对单克隆抗体保护能力相对差异的贡献，研究了它们与几种不同经典血清型的沙门氏菌参考菌株的反应性。尽管对不同菌株的反应性存在一些明显差异，但这种方法不足以确定这些单克隆抗体的精细特异性。本研究结果提供了证据，表明对沙门氏菌LPS的O-多糖区域具有特异性的单克隆抗体可以保护C3H小鼠免受同源菌株的攻击。
