GENOTYPIC DIVERSITY OF REASSORTANTS BETWEEN SIMIAN ROTAVIRUS SA11 ANDHUMAN ROTAVIRUSES HAVING DIFFERENT ANTIGENIC SPECIFICITIES AND RNA PATTERNS

A total of 200 clones of reassortants were generated in vitro between simian rotavirus SA11 (SA11-L2 strain) and each of five human rotaviru s (HRV) strains with different antigenic specificities and RNA, patter ns. When culture fluid coinfected with parent viruses was subjected to repeated selection with anti-HRV-VP4 and anti-SA11-VP7 neutralizing m onoclonal antibodies, all yielded progenies were antigenic mosaic reas sortants possessing VP4 and VP7 derived from SA11 and HRV, respectivel y. In genomic analysis of viral RNA by PAGE, two and five different ge notypes were identified in 40 clones, generated between SA11 and HRV s train Hochi (G serotype 4, G4) and between SA11 and KU (G1), respectiv ely. In contrast, 11 and 17 genotypes were found in progenies between SA11 and subgroup I G2 HRV strain HN126 or DS-1, respectively. Althoug h SA11 genes, except for the VP7 gene, were predominant in most reasso rtants, gene 5 was preferentially selected from HRV. Incorporation of HRV segments 1,3 and 10 into progenies was moire frequent in SA11 x HN 126 and SA11 x DS-1 reassortants than in other reassortants. These res ults indicated that the extent of diversity of reassortant genotypes d iffers between the two groups of the parental HRV strain; one has subg roup I specificity and a short RNA pattern (DS-1 genogroup), while the other has subgroup II specificity and a long RNA pattern (Wa genogrou p).