RESUMO
The purpose of this study is to report the results of the authors' investigation to apply the western blot technique (WB UP-LCS) in the diagnosis of human immunodeficiency virus type 1 (HIV-1) infection. To do this, the authors separated the proteins of the HIV-1 virus by electrophoresis, based on their molecular weight, in poliacilamide gel with SDS (SDS-PAGE) during 3 hours at 200 volts. Then they electrotransferred these proteins to nitrocellulose paper during four hours at 200 milliamperes, with the aid of external cooling. The nitrocellulose strips were evaluated considering the incubation time (1 and 16 hours), two conjugates (human anti IgG with Peroxidase and human anti IgG Biotin plus Streptatividine with Peroxidase) and two dilutions of the patients' sera (1/50 and 1/100). Based on their results the Authors conclude that, in the first place, the optimal conditions for the test include a dilution of 1/100 of the patients serum, incubation of the serum for 16 hours and the use of the conjugate of anti human IgG with Biotin and Streptavidine with Peroxidase; secondary, that the immunologic reactivity against proteins p24 and gp 160/120 is the most important diagnostic criterion for the confirmation of infection with HIV-1 and that they obtained a diagnostic correlation of 100% at a cost which was 5 to 7 times less than that of the commercial system