J Colomina1, J Raga, M T Gil, J Buesa. 1. Servicio de Microbiología, Facultad de Medicina, Hospital Clínico Universitario, Universidad de Valencia. javier.colomina@uv.es
Abstract
BACKGROUND: The analysis of the immune response to rotavirus infection and the characterization of the viral antigens recognized by specific antibodies are of great concern in evaluating the protection against rotavirus. MATERIAL AND METHODS: The levels of rotavirus-specific fecal (sIgA) and serum antibodies (IgM, IgG and IgA) were evaluated by ELISA in 25 children with acute gastroenteritis for rotavirus, in 11 of them during the acute and convalescent phases. The specificity of serum antibodies to viral polypeptides was characterized by immunoblotting. RESULTS: Serum IgM antibodies with a geometric mean titer (GMT) of 1/3,973 were the predominant antibodies detected during the acute phase. In comparison, IgG and IgA serum antibodies and sIgA coproantibodies levels were higher in the convalescent phase (GMT = 1/5,799, 1/257 and 1/137 respectively). Significant differences were observed for all the isotypes of immunoglobulins evaluated during the infection and in the convalescence (p < 0.01). Rotavirus-specific serum antibodies recognized mainly the structural VP6, VP7 and VP3/VP4 proteins. Other polypeptides also detected were VP1, VP5 and the non-structural NS34 protein. CONCLUSIONS: Rotavirus infection produce an intense humoral immune response both in serum and in the gut. Specific antibodies react against structural proteins of the internal (VP6) and external (VP7) capsids of rotavirus.
BACKGROUND: The analysis of the immune response to rotavirus infection and the characterization of the viral antigens recognized by specific antibodies are of great concern in evaluating the protection against rotavirus. MATERIAL AND METHODS: The levels of rotavirus-specific fecal (sIgA) and serum antibodies (IgM, IgG and IgA) were evaluated by ELISA in 25 children with acute gastroenteritis for rotavirus, in 11 of them during the acute and convalescent phases. The specificity of serum antibodies to viral polypeptides was characterized by immunoblotting. RESULTS: Serum IgM antibodies with a geometric mean titer (GMT) of 1/3,973 were the predominant antibodies detected during the acute phase. In comparison, IgG and IgA serum antibodies and sIgA coproantibodies levels were higher in the convalescent phase (GMT = 1/5,799, 1/257 and 1/137 respectively). Significant differences were observed for all the isotypes of immunoglobulins evaluated during the infection and in the convalescence (p < 0.01). Rotavirus-specific serum antibodies recognized mainly the structural VP6, VP7 and VP3/VP4 proteins. Other polypeptides also detected were VP1, VP5 and the non-structural NS34 protein. CONCLUSIONS:Rotavirus infection produce an intense humoral immune response both in serum and in the gut. Specific antibodies react against structural proteins of the internal (VP6) and external (VP7) capsids of rotavirus.