Homotypic serum antibody responses to rotavirus proteins following primary infection of young children with serotype 1 rotavirus

Abstract

The class-specific antibody responses to serotype 1 rotavirus structural proteins were examined by immunoblotting with sera obtained from young children hospitalized with acute rotavirus diarrhea caused by serotype 1. All were believed to be primary infections. Three consecutive serum samples were obtained from 16 patients during the acute and convalescent phases of the disease and then approximately 4 months later. Immunoglobulin G (IgG)-class antibody responses to two inner capsid proteins (VP2 and VP6) and to the major homologous outer capsid protein (VP7) were detected in all patients. Antibody responses to VP6 were rapid, increased in intensity during 20 to 40 days after the onset of symptoms, and persisted for more than 4 months. Responses to VP2 and VP7 were more delayed, were maximal in convalescent-phase sera, and decreased markedly in intensity 4 months after the onset of symptoms in the majority of children. Two patients with evidence of mixed infection showed persisting high levels of antibody to VP7. Responses to the outer capsid protein VP4 were detected in 67% of patients, peaked at 20 to 40 days after the onset of symptoms, and were no longer detected at 4 months in the majority of patients. It is likely that the immunoblotting technique underestimated responses to VP4. Acuteand convalescent-phase sera (known to contain antirotavirus IgM or IgA measured by enzyme immunoassay) were also examined by immunoblotting. IgM-and IgA-class antibody responses to viral proteins VP2, VP4, and VP7 appeared to be qualitatively identical to those observed for IgG in the same serum samples.2 to 4 weeks after the onset of gastroenteritis in all cases,

Serologic responses by immunoblot following natural infection with rotavirus serotypes G1 and G4 in children

“…Homotypic anti-VP7 developed in most patients following infection with either serotype G1 (80%) or G4 (86%). Similar findings have been reported by Richardson and Bishop [1990] and Richardson et al [1993] when analyzing the immune response following natural infection. Homotypic anti-VP4 antibodies were found in 60% of children following P1A[8] infection; 7 (70%) of 10 G1-infected and 2 (40%) of 5 G4-infected.…”

“…No homotypic anti-VP4 antibodies were found following G4, P2A[6] infection (0 of 2). The findings for anti-VP4 responses for our G1-infected patients are similar to those of Richardson and Bishop [1990], who described 67% of their G1-infected patients developing anti-VP4 IgG antibodies. The latter study differs from ours, however, in that the authors noted that the majority of their G4-infected patients also developed homotypic anti-VP4 [Richardson et al, 1993].…”

“…Rotaviruses of serotype G1, P1A[8] (strain WA); G2, P1B[4] (strain DS-1); G3, P1A[8] (strain P); or G4, P2A[6] (strain ST-3) specificity were propagated on MA104 cells, purified by extraction with trichlorotrifluoro-ethane (Freon), concentrated 200-fold by ultracentrifugation, and resuspended in Tris-buffered saline (0.02-M) with 10-mM CaCl 2 as described by Rich-ardson and Bishop [1990]. Before use, each virus preparation was both G-and P-serotyped to verify its identity.…”

“…Svensson et al [1987], using a radioimmunoprecipitation assay, found VP2 and VP6 most antigenic and anti-VP7 present in only 3 of 8 infected children. Richardson and Bishop [1990], using an immunoblot assay, assessed the homologous antibody response to G1 infection in 16 patients and found anti-VP2, -VP6, and -VP7 in all cases, and anti-VP4 in 67% of the cases. Using radio-immunoprecipitation, Richardson et al [1993] studied 14 patients with G1 and 6 patients with G4 infection and described homologous and heterologous anti-VP2, -VP6, and -VP4 response in the majority of patients; the study found that homologous anti-VP7 was common following G1, but not G4, infection, and heterologous anti-VP7 was infrequent.…”

Measurement of antirotavirus IgM/IgA/IgG responses in the serum samples of Indian children following rotavirus diarrhoea and their mothers

“…Children below 2 years of age are the most susceptible to rotavirus infection, however, susceptibility to infection with rotavirus continues throughout life with the most severe disease being associated with the primary infection of the infants [Richardson and Bishop, 1990]. Prospective studies show that primary infections are more often symptomatic than asymptomatic [Bishop, 1986].…”