Survival of immunoglobulin G-opsonized Toxoplasma gondii in nonadherent human monocytes.
Infect Immun
; 63(11): 4290-4, 1995 Nov.
Article
em En
| MEDLINE
| ID: mdl-7591060
ABSTRACT
Toxoplasma gondii is a protozoan parasite that is able to penetrate human monocytes by either passive uptake during phagocytosis or active penetration. It is expected that immunoglobulin G (IgG) opsonization will target the parasite to macrophage Fc gamma receptors for phagocytic processing and subsequent degradation. Antibody-opsonized T. gondii tachyzoites were used to infect nonadherent and adherent human monocytes obtained from the peripheral blood of seronegative individuals. The infected monocytes were evaluated for the presence of intracellular parasites and the degree of parasiticidal activity. A marked difference in both the numbers of infected macrophages and numbers of parasites per 100 macrophages was observed in the nonadherent cells when compared with those of the adherent cell population. When macrophage Fc gamma receptors were down-modulated, opsonized tachyzoites retained their ability to penetrate the host cell at a rate similar to that observed for unopsonized parasites. These results suggest that antibody opsonization of T. gondii does not prevent active penetration of human monocytes by the parasite and, furthermore, has little effect on intracellular replication of the parasite.
Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Toxoplasma
/
Monócitos
Limite:
Animals
/
Humans
Idioma:
En
Revista:
Infect Immun
Ano de publicação:
1995
Tipo de documento:
Article
País de afiliação:
Estados Unidos