Cytokine gene expression in peripheral blood mononuclear cells (PBMC) from patients with pharmacologically treated cystic echinococcosis

Abstract

The influence of pharmacological treatment on the immune response of patients with Echinococcus granulosus infection was evaluated by reverse transcriptase-polymerase chain reaction (RT-PCR) to determine mRNA expression for IL-12 p35, IL-12 p40, interferon-gamma (IFN-gamma), tumour necrosis factor-alpha (TNF-alpha) and IL-4 in PBMC from 12 patients before and after chemotherapy and from seven uninfected controls. Most patients' PBMC showed measurable amounts of IL-12 p35, IL-4, IFN-gamma and TNF-alpha mRNA in parasite antigen-stimulated and unstimulated cultures. Conversely, IL-12 p40 mRNA was detected almost exclusively in successfully treated patients (86%) after therapy. In these patients semiquantitative analysis of RT-PCR products showed a significant difference between IL-12 p40 mRNA mean levels before and after therapy (P = 0.03 in parasite antigen-stimulated cultures; P = 0.001 in unstimulated cultures). IL-4 mRNA was weakly expressed before therapy and more highly so after treatment in both groups of patients and under both culture conditions; IL-4 mRNA reached its highest level in post-therapy PBMC from patients in whom therapy failed (stimulated cultures). IFN-gamma and TNF-alpha mRNA expression increased in patients who responded to therapy and decreased in patients who did not. In contrast to IL-12 p35, IFN-gamma and TNF-alpha mRNAs, IL-12 p40 and IL-4 mRNAs were detected exclusively in patients, suggesting a close relationship between these two cytokines and cystic echinococcosis. Our findings indicate that chemotherapy influences the immune response, thus determining changes in Th1/Th2 cytokine mRNA patterns, predominantly in IL-12 p40 and IL-4 mRNA expression.

Modulation of Human Immune Response byEchinococcus granulosusAntigen B and Its Possible Role in Evading Host Defenses

“…In this way we directly evaluated the protein's action on cell motility, irrespective of its chemoattractant properties. The effects of AgB on circulating PMN from patients with CE might be interesting to evaluate, though we doubt whether the results would differ from those in cells from uninfected con- In previous in vitro and in vivo studies we found high Th1 cytokine concentrations (IFN-␥) in patients who responded to chemotherapy and high Th2 cytokine concentrations (IL-4 and IL-10) in patients who did not (32,33,34). If Th1 responses begin to damage the parasite, then it would be to the parasite's advantage to create a Th2 bias through the release of antigens that induce Th2-promoting cytokines, such as IL-4 and IL-13.…”

“…In a previous study investigating IL-12 gene expression in pharmacologically treated patients with CE, we suggested a role of this cytokine in resolving the disease, probably by promoting Th1 cell activation (IFN-␥) (34). In alveolar echinococcosis, in vivo treatment with recombinant IL-12 showed that this cytokine is of crucial importance in inhibiting larval growth (mainly through production of IFN-␥), suggesting its usefulness in therapy (17).…”

“…Observing that the 12-kDa subunit of AgB is a protease inhibitor with the ability to inhibit neutrophil recruitment Shepherd et al first suggested the role of this antigen in escape mechanisms from the early natural immunity (37). In studying acquired immunity to E. granulosus we have previously reported that crude sheep hydatid fluid (SHF) elicits both Th1 and Th2 cell activation: the Th2 response benefits the parasite, whereas the Th1 response benefits the host (31,32,33,34). Thus, the characterization of parasite-derived immunoregulatory molecules associated with Th1 or Th2 polarization is an important prerequisite for identifying the basis of resistance or suscepti-bility.…”

Recent Advances in the Immunology and Serological Diagnosis of Echinococcosis

“…Both in vitro and in vivo studies have shown that high levels of the Th1 cytokine IFN-γ were found in patients who responded to chemotherapy, whereas high levels of Th2 cytokines l (IL-4 and IL-10) occurred in patients who did not (Rigano et al, 1999b;Rigano et al, 1999a;Rigano et al, 1995b;Rigano et al, 1995a).…”

Concepts in Immunology and Diagnosis of Hydatid Disease

“…In hydatid infections, both cell population profiles remain highly expressing, at least in cysts that survive the immune response. Elevated levels of IL-4, IL-5, IL-6, and IFN-␥ are produced in vitro by peripheral blood mononuclear cells (PBMC) isolated from infected human subjects and stimulated by HCF antigens (213)(214)(215)(216)(217)(218)(219). Elevated cytokine levels were also measurable in the sera from hydatid disease patients with lung and liver involvement (249).…”