Immunogenicity of RNA-protein fraction isolated from axenic Entamoeba histolytica (NIH:200).
The immunogenicity of Entamoeba histolytica RNA (EhRNA) was studied in guinea-pigs. Animals immunized with a single dose of EhRNA and Freund's complete adjuvant (FCA) showed a high level of cell-mediated immune response (CMIR) as assessed by percent leucocyte migration inhibition (74.8 +/- 2.9) after 1 week of immunization. This response faded away gradually and by week 5 after immunization the percent leucocyte migration inhibition was 27.1 +/- 8.27, which is quite close to control values. The immunogenic activity of EhRNA was found to be specific, since yeast RNA failed to elicit immunological responses, and was RNase-sensitive. The CMIR could be maintained at its high level by giving boosters or multiple doses. Anti-EhRNA antibodies (haemagglutinins or precipitins) could not be demonstrated at any stage.
D000818:Animals; D000917:Antibody Formation; D004748:Entamoeba histolytica / Q000235:genetics*; D005260:Female; D005620:Freund's Adjuvant; D006168:Guinea Pigs; D007111:Immunity, Cellular; D007961:Leukocyte Migration-Inhibitory Factors / Q000032:analysis; D008297:Male; D012313:RNA / Q000276:immunology*; D012710:Serum Albumin, Bovine / Q000276:immunology; D013997:Time Factors
D007961:Leukocyte Migration-Inhibitory Factors; C029180:methylated bovine serum albumin; D012710:Serum Albumin, Bovine; D012313:RNA; D005620:Freund's Adjuvant