Antibody-mediated opsonization of red blood cells in parvovirus B19 infection.
Red blood cells (RBCs) express abundantly parvovirus B19 receptor, and their role in the dissemination or clearance of B19 infection is unknown. In this study, we report that in early, acute or persistent infection, B19 viremia is mostly associated with RBCs. The capacity of different patients' plasma or IgG to opsonize RBCs collected from patients with early B19 infection, was investigated. The highest opsonization activity was observed with plasma or IgG fractions from patients with past B19 infection. In contrast, IgG samples from patients with acute or persistent infection showed no or little opsonization activity. The depletion of antibodies specific to B19 VP1, but not VP2, from IgG samples, resulted in a significant suppression of opsonization. Furthermore, IgG samples preincubated with heated B19 particles exposing VP1-unique (VP1u) region were unable to opsonize RBCs. These observations clearly suggest a role for anti-VP1u IgG in the opsonization of RBC-bound B19 particles.
Chehadeh
Wassim
W
Virology Unit, Department of Microbiology, Faculty of Medicine, Kuwait University, PO Box 24923, Safat 13310 Kuwait.
Halim
Medhat A
MA
Al-Nakib
Widad
W
D000293:Adolescent; D000328:Adult; D000368:Aged; D000914:Antibodies, Viral / Q000097:blood*; D036022:Capsid Proteins / Q000276:immunology; D016022:Case-Control Studies; D002648:Child; D002675:Child, Preschool; D016731:Erythema Infectiosum / Q000097:blood* / Q000276:immunology* / Q000821:virology; D004912:Erythrocytes / Q000276:immunology* / Q000821:virology*; D005260:Female; D006801:Humans; D007074:Immunoglobulin G / Q000097:blood; D007075:Immunoglobulin M / Q000097:blood; D066298:In Vitro Techniques; D008297:Male; D008875:Middle Aged; D009895:Opsonin Proteins / Q000097:blood*; D010322:Parvoviridae Infections / Q000097:blood* / Q000276:immunology* / Q000821:virology; D016732:Parvovirus B19, Human / Q000276:immunology* / Q000472:pathogenicity* / Q000502:physiology; D055815:Young Adult
D000914:Antibodies, Viral; D036022:Capsid Proteins; D007074:Immunoglobulin G; D007075:Immunoglobulin M; D009895:Opsonin Proteins; C095547:capsid protein VP1, parvovirus B19; C095548:capsid protein VP2, parvovirus B19