Role of Immune Complexes from Pacients with Different Clinical Forms of Schistosomiasis in the Modulation of In Vitro Granuloma Reaction

Abstract

Schistosomiasis is a disease whose pathology is strongly related to the granulomatous reaction formed around parasite eggs trapped in host tissues. Studies have shown that the chronic intestinal form (INT) of this infection is associated with a variety of immunoregulatory mechanisms which lead to a diminished granulomatous reaction. Using an in vitro model of granuloma reaction, we show that immune complexes (IC) isolated from sera of INT patients are able to reduce granulomatous reaction developed by peripheral blood mononuclear cells (PBMC) from acute (AC), INT and hepatosplenic (HE) patients to soluble egg antigen (SEA)-conjugated polyacrylamide beads (PB-SEA). This inhibitory activity is also observed in cell proliferation assay of PBMC from INT and HE patients stimulated with SEA and adult worm antigen (SWAP

Cytokine profile, proliferation and phosphorylation of ERK1/2 and Akt in circulating mononuclear cells from individuals during the chronic intestinal phase of Schistosomiasis mansoni infection

“…The fact that the PBMCs from the NI and XTO patients were obtained from two distinct endemic areas may explain the differences between our studies. The population living in endemic areas is heterogeneous, and the immunological profile of each individual is a result of re-infection, delayed hypersensitivity and severity of the disease [5]. …”

“…The exudative-necrotic granuloma of the acute phase becomes smaller and contains fewer inflammatory cells. This lack of inflammatory cells appears to be less pathogenic to the liver cells [1-5]. Schistosoma infection causes a range of morbidities, which is influenced to a large extent by the nature of the induced immune response and its effects on granuloma formation.…”

Acute schistosomiasis mansoni: revisited and reconsidered

“…Immune complexes, usually cleared by reticuloendothelial cells, are probably responsible for some manifestations of the acute phase, such as cerebral and cutaneous vasculitis , Jauréguiberry et al 2007, and pericardial and pleural effusions (Taliberti et al 1978, Lawley et al 1979, Rezende et al 1997.…”

Clinical and immunological consequences of human T cell leukemia virus type-I and Schistosoma mansoni co-infection

“…Several factors have been associated to liver fibrosis including the genetic background, the degree of infestation and host immunological response. Initially, experimental studies suggested that type-1 cytokines were associated with granuloma formation (Leptak & McKerrow 1997, Rezende et al 1997. However, more recent date point to the importance of type-2 cytokines such as IL-4 and IL-13 in inducing fibrosis and the ability of IL-12 and IFN-γ to decrease it (Wynn et al 1994, Chiaramonte et al 1999b, Jankovic et al 1999.…”

“…Liver fibrosis is the most important pathological finding in schistosomiasis, being registered in about 5% of chronically S. mansoni infected patients (Bina & Prata 2003). Although initial experimental studies suggested that type-1 cytokines were associated with granulomatous reaction to S. mansoni infection (Leptak & McKerrow 1997, Rezende et al 1997, its clear from current data that type-2 cytokines play a primary role in inducing fibrosis, whereas the IFN-γ (type-1 cytokine) acts as an endogenous down regulator of the response (Wynn et al 1994, Chiaramonte et al 1999a, Jankovic et al 1999. Simultaneous infection between HTLV-I and Strongyloides stercoralis decreases the predominant type-2 immune response in patients with strongyloidiasis (Neva et al 1998, Porto et al 2001a) as well as S. stercoralis-specific and total IgE antibodies (Neva et al 1998, Porto et al 2001b).…”