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The complete nucleotide sequence of the genome of human rhinovirus type 89 was determined from the cDNA that had been cloned into Escherichia coli. The genome is 7152 nucleotides long and contains a single large open reading frame of 2164 codons. Translation commences at position 619 and ends 42 nucleotides before the poly(A) tract. The positions of three proteolytic cleavage sites in the polyprotein were determined by N-terminal amino acid sequencing of the capsid proteins; the remainder were predicted from comparisons with other picornaviruses. Extensive similarity between the derived amino acid sequences of human rhinovirus types 89 and 2 was found, whereas the similarity between human rhinovirus types 89 and 14 was considerably less. It is apparent that human rhinoviruses may be more closely related than has been previously thought.Human rhinoviruses, members of the picornavirus family, are the main causative agents of the common cold (1). The acquisition of immunity to the disease is, however, hampered by the existence of more than 100 antigenically distinct serotypes (2). Paradoxically, recent work has shown that all except eight rhinovirus serotypes so far tested use the same cellular receptor (3, 4). Determination of the x-ray crystal structure of human rhinovirus 14 (HRV14) by Rossmann et al. (5), together with the analysis of isolates of HRV14 resistant to neutralization by monoclonal antibodies, has allowed the identification of four distinct antigenic sites on the surface of the virus that have been designated neutralization immunogens (NIms) (5, 6). Furthermore, a depression on the virus surface, spatially distinct from the NIms, was proposed to be the viral receptor binding site. Comparisons of the complete nucleotide sequences of human rhinovirus 2 (HRV2) and HRV14 have also helped illuminate evolutionary relationships within the rhinovirus genus (7-9). Comprehensive analysis of the derived amino acid sequences has revealed that these two viruses share only =50% of their residues, indicating that the rhinovirus genus may be rather diverse.An understanding of the relationships among rhinovirus serotypes will be useful in assessing the potential of antiviral agents and vaccines. To this end, the complete nucleotide sequence of human rhinovirus 89 (HRV89) and the Nterminal amino acid sequences of three coat proteins have been determined. Extensive sequence similarity is observed between HRV89 and HRV2; however, regions corresponding to the NIms are markedly different. Furthermore, the similarity between HRV2 and HRV89 is much greater than that between HRV89 and HRV14, although HRV89 and HRV14 belong to the same receptor group.

SUMMARYUse has been made ofa monoclonal antibody (designated 8F5) to map a neutralizing epitope on the viral capsid protein VP2 of human rhinovirus 2 (HRV2). This antibody which was raised against the native virus, neutralizes HRV2 and is also capable of recognizing denatured VP2 on Western blots. To examine the binding site of 8F5, VP2 of HRV2 was expressed in Escherichia coli. Deletions starting at the 3' end were then introduced into the gene for VP2 using Bal-31 nuclease. Polypeptides shortened at the carboxy terminus of VP2 were obtained from the deletions and were blotted onto nitrocellulose. The samples were then probed with monoclonal antibody 8F5. Recognition by 8F5 was maintained as long as the expressed polypeptide contained the VP2 sequence up to amino acid 164 or beyond. However, when the VP2 sequence was truncated to amino acid 153 or less 8F5 was no longer able to bind. The neutralization epitope (or part of it) recognized by 8F5 on VP2 is therefore located between amino acids 153 and 164.

SUMMARYThe human rhinovirus minor group receptor was extracted from HeLa cell membranes and partially purified. Receptor activity was detected on Western blots by binding of 3sS-labelled human rhinovirus serotype 2 to the immobilized protein at a position corresponding to an Mr of 120 x 103.

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