Analysis of antigenically intermediate strains of subgenus B and D adenoviruses from AIDS patients.

We carried out detailed antigenic and restriction enzyme (RE) analyses on the subgenus B and D adenovirus isolates from 48 AIDS patients. These isolates were unusual both in the diversity of serotypes and in the number of intermediate strains identified. All unusual isolates were strain-purified and tested by serum neutralization (SN) and hemagglutination-inhibition (HI) tests with reference horse and rabbit antisera to all the prototype human adenoviruses; conversely, rabbit antisera were prepared to 16 selected strains from this study and tested by SN and HI with all prototype viruses. Among subgenus B strains, 6 DNA variants of Ad 11 isolates were distinguished by endonucleases BamHI, BglII, BstEII, HindIII, and SmaI. The D 2 variant of Ad 11 was prominent with 5 isolates, and 7 other isolates differed from D 2 in only 1 or 2 enzymes. HindIII was the most discriminative endonuclease for Ad 11 and related strains. Within subgenus D, there were 16 isolates of intermediate strains, including 4 intermediate types related to new Ad types 43-47. The RE patterns of subgenus D strains showed fragment distributions typical of subgenus D, with various unique patterns. Particular care was taken to analyze multiple strains from the same patient, recovered as much as 8 months apart, for evidence of genetic changes. The possible long-term infections with these viruses may provide the opportunity for mutations and recombination to occur, with the resultant generation of a variety of new strains of adenoviruses.