Characterization of Monoclonal Antibodies against Etiological Agents of Weil's Disease

Abstract

Monoclonal antibodies against etiological agents of Weil's disease were produced by cell fusion technology. Twenty hybridomas were produced through the fusion of P3×63Ag8.653 cells with spleen cells from BALB/c mice immunized against Leptospira interrogans serovar icterohaemorrhagiae RGA strain and serovar copenhageni Shiromizu and M20 strains. Reactivities of the antibodies produced by the hybridomas were determined by the microscopic agglutination test. Among the five hybridoma antibodies to the RGA strain, two reacted specifically to serovar icterohaemorrhagiae, two reacted to serovar icterohaemorrhagiae at a high titer and serovar copenhageni at a low titer, and one reacted to serovars icterohaemorrhagiae, copenhageni, pyrogenes, and canicola. Of the ten hybridoma antibodies to the Shiromizu strain, one reacted specifically to serovar copenhageni, seven reacted to both serovars copenhageni and icterohaemorrhagiae at almost the same titer, and two exhibited intermediate properties. Of the five hybridoma antibodies to the M20 strain, three reacted to both serovars copenhageni and icterohaemorrhagiae at almost the same titer, one reacted to serovar copenhageni at a low titer and serovar icterohaemorrhagiae at a high titer, and one reacted to serovars copenhageni, icterohaemorrhagiae, and pyrogenes. The results revealed that each serovar has its own antigen(s) and their common antigens. In addition, 20 strains of leptospires were recently isolated and tested with three monoclonal antibodies characterized by different reactivities. Twenty strains were clearly identified by their antibodies, i.e., 16 strains were identified as serovar icterohaemorrhagiae and three strains were identified as serovar copenhageni. The remaining strain, which was not agglutinated by three antibodies, was identified as serovar autumnalis by an agglutination test with immune rabbit sera.

Isolation and Characterization of Leptospira spp. from Raccoons in Japan

“…Most but not all serovars gave unique PFGE patterns using the restriction enzyme NotI, although the L. interrogans serovar Copenhageni and Icterohaemorrhagiae were indistinguishable by NotI-PFGE [5,6]. These two serovars are also very difficult to distinguish by serological methods [11]. KRC-146 reacted equally with the reference antisera of serovars Copenhageni and Icterohaemorrhagiae (Data not shown) and showed identical banding pattern to these reference strains on PFGE (Fig.…”

Genome conservation in isolates of Leptospira interrogans

“…Each of the 14 serovars belonging to serogroup Icterohaemorrhagiae has its own specific fingerprint apart from the two serovars, icterohaemorrhagiae and copenhageni (Fig. 2), which are very difficult to distinguish by serological methods (20) and which have identical PFGE Notl restriction profiles. These two serovars have been reported previously to have identical EcoRI or other endonuclease restriction patterns (28,34) and identical DNA-rRNA hybridization patterns (26).…”

Restriction Endonuclease DNA Analysis of Leptospira interrogans Serovars Icterohaemorrhagiae and Copenhageni

“…Taxonomically, serovar icterohaemorrhagiae and serovar copenhageni were differentiated by the conventional serological methods , and in our previous study using monoclonal antibodies (7,14) the serovar icterohaemorrhagiae RGA and serovar copenhageni M20 strains were easily distinguished from each other . In this study, however, these two serovars were not differentiated by endonuclease DNA analysis with the 15 endonucleases used.…”

“…There have been some attempts at reclassification of leptospires using these new techniques (7,8,13,15,16 …”