Interferon-γ production by peripheral blood mononuclear cells from residents of an area endemic for Schistosoma mansoni

Abstract

During human schistosomiasis host responses to antigens of various parasite life-cycle stages may contribute to whether the severe, hepatosplenic state develops or the patient remains relatively asymptomatic throughout infection, and may play a role in resistance. This study evaluated production of interferon gamma (IFN-gamma) in vitro by schistosome antigen-stimulated peripheral blood mononuclear cells (PBMCs) from asymptomatic patients, and by PBMCs from apparently uninfected, untreated persons living in areas endemic for Schistosoma mansoni ('endemic normals'). IFN-gamma production parallels PBMC proliferation in that schistosomal egg antigens stimulate patent patients' cells poorly, but strongly stimulate PBMCs from 'endemic normals'. This is proportionally true for antigens from adult worms and cercariae. Although asymptomatic patent patients' cells produced little or no IFN-gamma in response to the 3 schistosomal antigenic extracts, their PBMCs, and PBMCs from 'endemic normals', produced expected amounts of IFN-gamma when exposed to phytohaemagglutinin. This implies that persons with patent infections have schistosome antigen-specific defects in their ability to respond to IFN-gamma production that are not exhibited by putatively resistant 'endemic normals'.

Cytokines as determinants of resistance and pathology in human Schistosoma mansoni infection

“…These results contrast significantly with those observed in PBMC cultures from patients in the chronic phase of the disease. Furthermore, we demonstrated that IFN-γ secretion correlates with resistance to infection, supporting a role of the Th1 response in immunity to S. mansoni (25).…”

Cytokine profile associated with chronic and acute human schistosomiasis mansoni

“…Our results showed low levels of IFN-γ production in infected patients with the IN clinical form of schistosomiasis (Zwingenberger et al 1991, Viana et al 1994, Silveira et al 2004. When compared to acute patients, we found higher IFN-γ levels detected in whole blood cultures stimulated with SEA or SWAP antigens from HS patients, which was also associated with degree II of hepatic fibrosis.…”

Cytokine Regulation of Human Immune Response to Schistosoma mansoni: Analysis of the Role of IL‐4, IL‐5 and IL‐10 on Peripheral Blood Mononuclear Cell Responses

“…We have centred our attention on IL-10 mainly because it has been shown to be an important cytokine in the modulation of the immune response of infected mice [30][31][32]. Our choice was also based on previous reports demonstrating that PBMC from INT do not produce IFN-g upon in vitro stimulation with SEA or SWAP [28,33,34].…”