Comparative study of Dot-immunogold silver staining and Dot-ELISA for the detection of serum antibodies against Wuchereria bancrofti.

Dot-immunogold silver staining (Dot-IGSS) and Dot-ELISA, using the soluble antigen of Brugia malayi, were employed to detect anti-Wuchereria bancrofti antibodies in 50 cases of Wuchereria bancrofti microfilaremia. The positive rates were 100% and 90% in Dot-IGSS and Dot-ELISA respectively. The average titer in the 45 positive cases was 1:184 (1:10-1:2560) for Dot-IGSS and 1:150 (1:10-1:2560) for Dot-ELISA, with 30 cases showing the same titer in both tests, 13 cases showing higher titer in Dot-IGSS than in Dot-ELISA and 2 cases in the former showing lower titers than in the latter. There was a linear relationship between the titers of antibodies detected by Dot-IGSS and by Dot-ELISA (r = 0.8443). Dot-IGSS, similar to Dot-ELISA, is easy to carry out and the result is easy to read. It is seen that Dot-IGSS is highly sensitive and specific and is practicable for immunodiagnosis and surveillance of filariasis.