ABSTRACT
Taking Naegleria australiensis, a species of pathogenic free-living amoeba (isolated in Shanghai in 1986), as antigen, two cell lines which provided potentially permanent source of monoclonal antibodies were established by lymphocytic hybridoma technique. The results of identification showed that: (1) the two cell lines could secret two different kinds of McAbs; (2) both of the McAbs were IgG (by gel diffusion); (3) McAbs produced in BALB/c mice were at high concentrations. One of them had a titer of ≥1 : 8 192 and the other≥l : 1 024 (by enzyme linked immunosorbent assay). A decline of the titers after purification by salting-out method was shown. One of the purified McAbs had a titer of≥1: 2 024 and the other≥l : 128.We have adopted two ways of recovering cryopreserved cells : ordinary recovering and "direct" recovering. The latter way was more practical because it could reduce the cycle of antibody production, and avoid contamination and chromosome variation. Experiments with different doses of cells revealed that, if the latter way was used, the optimal dose was 3 to 5 ? 106 cells per mouse.