[Preparation of monoclonal antibodies against SARS coronavirus and staining usage in lung autopsy specimens].

OBJECTIVE: To prepare monoclonal antibodies against SARS coronavirus (SARS-CoV) on the purpose to explore the diagnosis methods of SARS.

METHODS: Female BALB/C mice were immunized with disinfected SARS-CoV (PUMC01) and the spleen cells were fused with myeloma NS-1 cells. The hybridoma cell strains were screened by enzyme-linked immunosorbent assay (ELISA), indirect fluorescent-antibody assay (IFA) and Western blotting. Autopsy lung tissue sections from SARS patients were stained with ascites of monoclonal antibody (M2 strain) by immunohistochemical technique.

RESULTS: Six strains of hybridomas that produced the monoclonal antibodies against SARS-CoV were obtained. The hybridomas were tested to have specific reactions with SARS-CoV and no cross-reactivates with other common respiratory disease causing pathogens. Of the 6 strains, 1 was identified as the immunoglobulin G3 (IgG3) isotype, 5 were IgG1. Western blotting showed that one strain (M2) reacted with 68000- Dalton (68KD) protein and four strains with 27000-dalton (27KD) protein. Band of M4 stain was not got by western blotting. Brown particles were seen in macrophages and pneumocytes in autopsy lung tissues from SARS patients.

CONCLUSION: Monoclonal antibodies we made were specific to the SARS-CoV, and they had been used to detect SARS-CoV in autopsy lung tissues specimens with positive results.