HETEROGENEITY OF IMMUNOGLOBULIN-G RESPONSE TO HELICOBACTER-PYLORI MEASURED BY THE UNWEIGHTED PAIR GROUP METHOD WITH AVERAGES

The heterogeneity of the immune response to Helicobacter pylori has al ways been noticed but has never been evaluated by obtaining a quantita tive measure. For this purpose, sera were tested by enzyme-linked immu nosorbent assay, and 207 positive serum specimens were subsequently te sted by immunoblotting, The presence or absence of six specific bands was noted, The homology of the different profiles of bands was measure d by calculating the Dice coefficient, and a dendrogram was constructe d. Thirty-four profiles were found,,vith each profile containing from 1 to 43 serum specimens, At a level of 72% similarity, 115 of the seru m specimens studied fell into eight profiles, At a level of 48% simila rity, 186 of the serum specimens studied fell into 22 profiles, The di fference in immunoblot profiles was probably linked to the host immune response, but infection with strains carrying different antigens cann ot be ruled out.