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I H Holmes

Publications and source records attributed to I H Holmes.

At least 19 recordsLinked to original sources
PubMed1992

Typing of human group A rotavirus with alkaline phosphatase-labeled oligonucleotide probes.

Rotavirus (RV) in stools of children less than 1 year of age with diarrhea in Bangkok in 1989 were serotyped by monoclonal enzyme immunoassay (MEIA). RNA extracted from these specimens was tested for hybridization with alkaline phosphatase (AP) and 32P-labeled oligonucleotides constructed from the nucleotide sequences of VP7 of human G types 1 (HuG1Ac), 2 (HuG2Ac), 3 (HuG3Ac), and 4 (HuG4Ac). Of 148 specimens that contained RV, 72% (106/148) hybridized with RV G type specific AP-labeled oligonucleotides compared to 47% (70/148) that were serotyped by MEIA (P less than 0.001). Of 68 specimens that contained only one VP7 serotype (G-type), as identified by MEIA, 94% (16/17) of G1, 90% (27/30) of G2, 57% (4/7) of G3, and 36% (5/14) of G4 RV hybridized with the AP-labeled HuG1Ac, HuG2Ac, HuG3Ac, and HuG4Ac oligonucleotides, respectively. The probes for G1, 2, 3, and 4 RV were specific for each G type. The results of hybridizing specimens with 32P- and AP-labeled oligonucleotides were similar. After transcription and amplification of cDNA of gene 9, AP-labeled RV G type specific oligonucleotides hybridized with 90% (134/148) of RV specimens. The high sensitivity of these nonimmunological techniques could be of value in identifying G types of RV during vaccine trials.

Alkaline Phosphatase↗
PubMed1992

A variant serotype G3 rotavirus isolated from an unusually severe outbreak of diarrhoea in piglets.

About 80% of faecal samples from severe outbreak of porcine diarrhoea (scours) were positive for rotavirus. Rotavirus positive samples were analyzed for their antigenic properties and amino acid sequences of the glycoprotein genes. These viruses could not be assigned to any serotypes using serotyping monoclonal antibodies (MAbs) developed for porcine rotaviruses [Nagesha and Holmes: Journal of Medical Virology 35:206-211, 1991b]. When two such viruses were isolated in cell culture and analyzed by neutralization tests using hyperimmune sera they showed only one way antigenic relation with both human and porcine viruses belonging to serotype G3. In addition none of the serotyping MAbs neutralized these two virus isolates. There was no base variation between VP7 genes of faecal and cell culture isolates. Predicted amino acid sequences of the VP7 gene showed marked epitope variation from other porcine type G3 isolates with amino acid substitutions and an additional glycosylation site at residue 238. This antigenic variation seen in rotaviruses appears similar to that of influenza viruses undergoing antigenic drift.

Amino Acid Sequence↗
PubMed1992

Molecular and serological analyses of two bovine rotaviruses (B-11 and B-60) causing calf scours in Australia.

Fecal specimens from 78 calves involved in outbreaks of calf diarrhea which occurred in three farms in Victoria, Australia, in 1988 were analyzed for rotaviruses. Thirty-eight samples were positive for group A virus antigen by enzyme-linked immunosorbent assay, and 20 of these contained viral double-stranded RNAs that could be detected by polyacrylamide gel electrophoresis. Two major electropherotypes could be observed, and a representative isolate of each electropherotype (isolates B-11 and B-60) was successfully adapted to grow in MA104 cells. Sequencing of the VP7 genes directly from RNA transcripts of fecal and cell culture-adapted viruses demonstrated that no base changes occurred in this gene upon adaptation to growth in MA104 cells. Sequencing also revealed that the VP7 protein of B-60 was closely related to G serotype 6 (G6) strains, whereas the B-11 sequence was significantly different from all previously published sequences except the recently reported VP7 sequences of bovine isolates 61A and B223, particularly across the antigenic regions A, B, and C. The other strains most closely related to B-11 by VP7 amino acid sequence analysis were G4 porcine strains BMI-1 and BEN-144 and G8 human strain 69M. Serotyping of B-11 and B-60 gave results that were in good agreement with the sequencing data. Hyperimmune typing sera clearly identified B-60 as a member of G6, whereas the B-11 strain reacted to moderate titers only with antisera to some G10 strains. Antiserum raised against B-11 neutralized some strains of G10 cross-reacted with porcine G4 type isolates BMI-1 and BEN-144 but not with other G4 strains or with rotaviruses of other mammalian G serotypes. Northern blot hybridization showed that B-11 was closely related to the recently reported bovine G10 strain B223, and they both possessed a similar segment 4 that was different from that of either UK bovine or NCDV rotavirus.

Amino Acid Sequence↗
PubMed1991

Direct serotyping of porcine rotaviruses using VP7-specific monoclonal antibodies by an enzyme immunoassay.

Employing a serotyping EIA test using MAbs both cell culture adapted and faecal porcine rotaviruses were classified into serotypes G3, G3/5, G4, and G5. The MAbs have confirmed and extended the serotyping results obtained using polyclonal antisera. These MAbs are therefore potential reagents for serotyping of porcine rotaviruses. Using subgroup specific MAbs serotypes G3, G3/5, and G5 were found to contain subgroup I antigens while G4 rotaviruses contained either subgroup II or subgroup I antigens.

Animals↗
PubMed1991

VP4 relationships between porcine and other rotavirus serotypes.

VP4 relationship of Australian porcine rotaviruses were identified using genetic reassortants and MAbs. All porcine virus isolates except BEN-144 appeared to share VP4 antigenicity with OSU virus. VP4 and BEN-144 virus (Gottfried-like virus) showed some antigenic relationships with the human neonatal viruses ST-3 and RV-3. In addition, VP4 of porcine CRW-8 showed antigenic relationships with simian SA-11. RRV and also canine K9 viruses, while that of porcine TFR-41 showed at least one way VP4 antigenic relatedness with UK bovine rotavirus. Furthermore, BMI-1 virus which is antigenically similar to an American virus SB1-A (a naturally occurring reassortant) may have arisen similarly by gene reassortment in nature in Australia.

Animals↗
PubMed1990

A porcine rotavirus strain with dual VP7 serotype specificity.

Porcine rotavirus MDR-13, which on original isolation showed a two-way antigenic relationship with human rotavirus RV-3, shows VP7 relationships with serotype G5 as well as G3 viruses upon gene reassortment. Analysis of porcine MDR-13 and the MD-UK reassortant revealed marked nucleotide and amino acid similarity of VP7 genes of these viruses with those of both serotype G3 and G5 viruses. Evolution of such a strain, possibly by sequential mutations in the VP7 gene, is discussed.

Amino Acid Sequence↗
PubMed1990

Serotyping of human group A rotavirus with oligonucleotide probes.

Rotaviruses (RV) in stools of children with diarrhea in Thailand were serotyped by monoclonal enzyme immunoassay (MEIA), and RNA extracted from these specimens were tested for hybridization with oligonucleotides constructed from the nucleotide sequences of VP7 of human serotypes 1, 2, 3, and 4. Of 178 specimens that contained RV as identified with a monoclonal antibody to group A RV, 84% (149/178) hybridized with serotype-specific oligonucleotides, and 42% (74/178) were serotyped by MEIA (P less than .001). Of the 74 specimens that were serotyped by MEIA, 92% (35/38) of type 1, 97% (34/35) of type 2, and the one type 4 RV hybridized with the HuG1Ac, HuG2Ac, and HuG4Ac oligonucleotides, respectively. RV strains identified in children in Thailand in 1987 and 1988 to which a serotype could be assigned by either method were either type 1, type 2, or, less often, type 4. Testing RV for hybridization with oligonucleotides for genes encoding VP7 is an alternate method of determining RV serotypes.

Antibodies, Monoclonal↗
PubMed1989

Comparative sequence analysis of VP7 genes from five Australian porcine rotaviruses.

The genes coding for the rotavirus major neutralizing protein, VP7, from 5 Australian porcine rotaviruses representing glycoprotein (i.e. VP7 or G) serotypes 3, 4, and 5, were sequenced. The genes were each 1,062 nucleotides long with two long open reading frames for proteins of either 326 or 297 amino acids and containing only one potential glycosylation site at amino acid position 69. When compared to the corresponding genes of human viruses, the porcine genes showed very high nucleotide and deduced amino acid homology. Sequence comparison also revealed that Australian porcine rotaviruses of G serotype 4 and 5 were similar to the corresponding porcine strains found in the U.S.A. and U.K., while G serotype 3 and 4 porcine rotaviruses were closely related to human G serotype 3 strain, RV-3 and serotype 4 strain, ST-3, respectively. These Australian rotavirus VP7 sequences were found to correlate with serological data we reported previously.

Amino Acid Sequence↗
PubMed1989

The VP7 gene of a new G serotype of human rotavirus (B37) is similar to G3 proteins in the antigenic c region.

The human rotavirus isolate B37 has a characteristic "super-short" RNA electropherotype and has been shown to represent a new VP7 serotype (M. J. Albert, L. E. Unicomb, and R. F. Bishop, 1987, J. Clin. Microbiol. 25, 183-185). The VP7 gene was cloned, and its nucleotide and predicted amino acid sequences were compared to other published VP7 gene sequences. Consistent with the serological evidence, two major antigenic regions of the B37 VP7 (i.e., regions A and B) differ in sequence from those of other G serotypes. Unexpectedly, the C antigenic region shows close similarity to G3 rotaviruses, but we were unable to detect a serological relationship using serotype 3 monoclonal antibodies.

Amino Acid Sequence↗
PubMed1989

Sequences of VP9 genes from short and supershort rotavirus strains.

Segment 10 genes from a short (RV-5, serotype G2) and a supershort (B37, a new G serotype) strain were cloned and their sequences compared to the (corresponding) segment 11 sequences of Wa, SA11, and UK rotaviruses. The determined nucleotide sequences were 817 (RV-5) and 947 (B37) bases in length and showed extensively conserved 5' noncoding and protein coding regions. The major open reading frame codes for a protein of 200 (RV-5) or 198 (B37) amino acids, and the newly proposed second open reading frame can code for a protein of 92 amino acids. Compared to long strain gene segments, the base sequences of the short and supershort strains were found to contain extended, AT-rich 3' noncoding regions which were not significantly homologous to each other, to other parts of the VP9 gene, or to other rotavirus genes that have been sequenced. The function(s) of these 3' regions is not apparent.

Amino Acid Sequence↗
PubMed1989

Neutralizing monoclonal antibodies against three serotypes of porcine rotavirus.

Using three serotypes (four strains) of cultivable porcine rotavirus as immunizing antigens, 10 neutralizing monoclonal antibodies were characterized. One VP4-specific monoclonal antibody directed against porcine rotavirus BEN-144 (serotype G4) neutralized human rotavirus strain ST-3 in addition to the homologous porcine virus. All nine VP7-specific monoclonal antibodies were highly specific for viruses of the same serotype as the immunizing rotavirus strain. One exception was the VP7-specific monoclonal antibody C3/1, which neutralized both serotype G3 and G5 rotaviruses. However, this monoclonal antibody did not neutralize the porcine rotavirus AT/76, also of serotype G3, nor mutants of SA-11 virus (serotype G3) which were selected with monoclonal antibody A10/N3 and are known to have mutations affecting the C antigenic region.

Animals↗
PubMed1988

Atypical rotaviruses in Australian pigs.

Atypical rotaviruses of two different electropherotypes were identified by PAGE in 16 out of 237 (5.3%) diarrhoeic faecal samples from piglets. A cDNA probe derived from a group B rotavirus hybridized strongly to two samples (of 3 tested) with electropherotypes suggestive of groups B or E, identifying them as group B. The electropherotype(s) of seven samples were typical of group C. By immunofluorescence, antibodies to group B, C, and E rotaviruses have been detected in sera from Australian sows, so it appears that atypical rotaviruses belonging to three different groups occur in pigs in this country.

Animals↗
PubMed1988

Nucleotide sequence of UK bovine rotavirus segment 4: possible host restriction of VP3 genes.

The bovine UK and simian SA11 rotaviruses are commonly used VP7-type reference strains. Since the surface protein VP3 is a significant neutralization antigen, it is important to fully characterize the VP3 types associated with current reference strains. Here we present the complete nucleotide and predicted amino acid sequence of VP3 from UK rotavirus (VP7 type 6) and compare it to the published sequences of SA114fm and RV-5. We also compare the deduced amino acid sequence covering the trypsin cleavage region of UK VP3 to 25 other available sequences. The UK protein is clearly different from that of bovine NCDV (another commonly used VP7 type 6 strain) and represents a second VP3 type associated with bovine rotaviruses. Our SA11 sequence differs from that determined by Lopez et al. [1985, Virology 144, 11-19; later referred to as SA114fM by Lopez et al. (1986, Virology 154, 224-227], their sequence being very similar to the published sequence of NCDV VP3. The significance of these results with regard to virus serotypes is discussed. Finally, in analyzing the nucleotide sequence surrounding the initiation codon, a potential hairpin-loop structure was identified which may be involved in translational regulation.

Amino Acid Sequence↗
PubMed1988

New porcine rotavirus serotype antigenically related to human rotavirus serotype 3.

Serotyping of porcine rotaviruses isolated in MA104 cells from Australian piglets with diarrhea showed that two strains belonged to serotype 3 and one strain was antigenically similar to the OSU strain of porcine rotavirus (serotype 5). In addition, neutralizing antibodies to human rotavirus serotype 4 (ST-3 strain) were detected in serum samples from sows in one area, and so it seems probable that porcine rotaviruses of at least three serotypes occur in Australia.

Animals↗
PubMed1988

Serotypic analysis of VP3 and VP7 neutralization escape mutants of rhesus rotavirus.

Neutralization escape mutants of simian rotaviruses (rhesus rotavirus and SA11) were tested in hemagglutination inhibition and neutralization assays against hyperimmune and infection sera to determine if mutation in an immunodominant epitope could enable neutralization escape. An SA11 mutant with a new glycosylation site at amino acid 211 of VP7 was shown to escape neutralization by hyperimmune but not infection sera.

Animals↗
PubMed1987

Marked sequence variation between segment 4 genes of human RV-5 and simian SA 11 rotaviruses.

The complete nucleotide sequence of dsRNA gene segment 4 of a human serotype 2 rotavirus, RV-5, was determined by sequencing overlapping cloned DNA copies of the gene. Segment 4 is 2359 base pairs in length and contains a single long open reading frame of 2325 bases capable of coding for a protein of 775 amino acids, with 5' and 3' non coding regions of 9 and 25 nucleotides respectively. Comparison with SA 11 segment 4 sequence reveals a moderately conserved trypsin cut site and an overall amino acid homology of 69.8 percent. One localized region of 126 amino acids is only 37.8 percent homologous. Localized frame shifts account for some of this variation, but at the nucleotide level the segment 4 sequences show more variability than other rotavirus genes that have been studied so far.

Amino Acid Sequence↗
PubMed1987

Glycosylation, an important modifier of rotavirus antigenicity.

Mutants of a non-glycosylated strain of SA 11 rotavirus (clone 28), were selected using a monoclonal antibody directed against the VP 7 protein. These mutants possessed an amino acid substitution at residue 238 of VP 7, whereas mutants of wild type SA 11 selected with the same antibody have previously been shown to contain a substitution at residue 211 (i.e., in the antigenic C region). In both cases the mutations produce new potential glycosylation sites, and these were found to be utilized. The mutations also lead to gross antigenic changes, and these were found to be reversible upon removal of the attached carbohydrate. The results suggest an important role for carbohydrate in influencing the exposure of antigenic determinants of the rotavirus serotype-specific protein, VP 7.

Amino Acid Sequence↗