[Effect of the extraction of LPS (R) on the demonstration of the serological response in acute brucellosis by immunoblotting].

In order to establish the possible influence of Brucella melitensis rough strains protein extracts contamination using LPS (R) in the immunoblotting evaluation of serologic response, we have studied sera samples from 41 patients with acute brucellosis before treatment was started and also from 62 healthy individuals (control group). A whole-cell B. melitensis 115 strain extract with an without LPS (R) was used. Extraction was carried using ether-chloroform of oil-phenol. Overall, more than 50% of patients showed an antibody response (protein bands 85, 53, 50, 47, 41, 38 and 28 kD) to both antigenic products. Less than 6.4% of the control group sera showed response to any of these protein bands. There were no significant differences in the frequency of response development against these proteins using the two antigen types. However, there was some disagreement when each individual band response was compared to its homologous band.