IDENTIFICATION OF A NEW VP4 SEROTYPE OF HUMAN ROTAVIRUSES

A new VP4 gene allele was identified by sequencing of two rotavirus st rains recovered from infants with diarrhea. Strains HAL1166 (a VP7 ser otype 8 human rotavirus from Finland) and PA169 (a VP7 serotype 6 huma n rotavirus from Italy) present 22-43% nucleotide sequence divergence and 14-45% amino acid divergence in the VP4 gene with rotaviruses belo nging to various VP4 gene alleles previously reported. Cross-neutraliz ation analysis between PA169 and rotaviruses belonging to the other re cognized VP4 (P) serotypes had previously shown that none of them was similar to PA169. Hyperimmune serum prepared against a reassortant wit h the VP4 gene of strain PA169 and the VP7 gene of serotype 2 strain D S1 failed to neutralize previously recognized human rotavirus VP4 sero types, indicating that PA169 represents a new VP4 serotype specificity . In addition, one of four neutralizing monoclonal antibodies directed to the VP4 of PA169 was specific for this virus, while three others h ad very limited cross-reactivity with rotaviruses possessing different VP4s. (C) 1994 Academic Press, Inc.