Dynamic Immune Profile in French Toxoplasmosis Patients.

BACKGROUND: Toxoplasma gondii infection is usually benign in Europe due to the strong predominance of type II strains. Few studies have been conducted to examine the immunological course of infection in humans and have yielded conflicting results, maybe influenced by heterogeneous parasite strains. METHODS: We measured 23 immune mediators in 39, 40, and 29 sera of French noninfected, acutely infected, and chronically infected immunocompetent pregnant women, respectively. RESULTS: Four different cytokine patterns were identified regarding their dynamics through infection phases. For 11 of the cytokines (IFN-ß, IFN-γ, IL-4, IL5, IL-6, IL-10, IL-12, IL-15, CXCL9, CCL2, and CSF2) the serum levels were significantly elevated during acute infection. The inflammatory mediators IL-1ß, IL-17A, IL-18, TNF-α, and CSF3 remained unchanged during acute infection, while they were significantly lower in chronically infected compared to noninfected patients. As for the anti-inflammatory cytokines TGF-ß and CCL5, their levels remained significantly elevated during chronic infection. We also observed a significant negative correlation of several cytokine concentrations with IgG levels, indicating a rapid decline of serum concentrations during the acute phase. CONCLUSIONS: These results indicate an anti-inflammatory pattern in chronically infected patients in a type II dominated setting and demonstrate the highly dynamic immune situation during acute infection.

Unusual presentation of toxoplasmosis with gastro-intestinal involvement in HLA non-identical stem cell transplantation.

Toxoplasmosis is a life-threatening infection in allogenic stem cell recipients usually involving the brain or retina and more rarely lungs or bone marrow. Digestive involvement has only been reported in AIDS patient. We report about a 38-year-old man who received a haploidentical allograft for acute myeloid leukemia and developed an unusual digestive presentation with severe protein-losing enteropathy following grade III acute digestive GvHD treated with steroids and ruxolitinib. Diagnosis was brought up because of concomitant brain involvement. Digestive symptoms fully recovered after treatment with sulfamethoxazole-trimethoprim. Digestive toxoplasmosis could be considered as a differential diagnosis or complication of severe digestive GvHD.

Ocular cytokinome is linked to clinical characteristics in ocular toxoplasmosis.

PURPOSE: To determine the cytokine levels in aqueous humor (AH) of Colombian patients with active ocular toxoplasmosis (OT), and to correlate them with their clinical characteristics. METHODS: 27 Cytokines/chemokines were assayed in 15 AH samples (nine patients with diagnosis of OT biologically-confirmed and six controls that underwent cataract surgery). Correlations were assessed between cytokine/chemokine levels, type of inflammatory response (Th1, Th2, Th17, Treg), and clinical characteristics. RESULTS: Th2 predominant response was related to more severe clinical features. The presence of VEGF and IL-5 was related to higher number of recurrences. Growth factors (VEGF, FGF, PDGF-ß), were related to higher number of lesions. Patients infected by type-I/III strains had a particular intraocular cytokine-pattern. CONCLUSIONS: Th2 response was related to more severe clinical characteristics in patients infected by Type I/III strains. IL-5 and VEGF were associated with recurrences. We correlate for the first time, specific cytokine-patterns with clinical characteristics and with the infecting Toxoplasma strain.

Severe South American ocular toxoplasmosis is associated with decreased Ifn-γ/Il-17a and increased Il-6/Il-13 intraocular levels.

In a cross sectional study, 19 French and 23 Colombian cases of confirmed active ocular toxoplasmosis (OT) were evaluated. The objective was to compare clinical, parasitological and immunological responses and relate them to the infecting strains. A complete ocular examination was performed in each patient. The infecting strain was characterized by genotyping when intraocular Toxoplasma DNA was detectable, as well as by peptide-specific serotyping for each patient. To characterize the immune response, we assessed Toxoplasma protein recognition patterns by intraocular antibodies and the intraocular profile of cytokines, chemokines and growth factors. Significant differences were found for size of active lesions, unilateral macular involvement, unilateral visual impairment, vitreous inflammation, synechiae, and vasculitis, with higher values observed throughout for Colombian patients. Multilocus PCR-DNA sequence genotyping was only successful in three Colombian patients revealing one type I and two atypical strains. The Colombian OT patients possessed heterogeneous atypical serotypes whereas the French were uniformly reactive to type II strain peptides. The protein patterns recognized by intraocular antibodies and the cytokine patterns were strikingly different between the two populations. Intraocular IFN-γ and IL-17 expression was lower, while higher levels of IL-13 and IL-6 were detected in aqueous humor of Colombian patients. Our results are consistent with the hypothesis that South American strains may cause more severe OT due to an inhibition of the protective effect of IFN-γ.

Cytokine profiles in toxoplasmic and viral uveitis.

BACKGROUND: Uveitis is a major cause of visual impairment throughout the world. Analysis of cytokine profiles in aqueous humor specimens may provide insight into the physiopathological processes that underly retinal damage in this context. METHODS: Using a multiplex assay, we determined the concentrations of 17 cytokines and chemokines in aqueous humor specimens obtained from patients with ocular toxoplasmosis or viral uveitis and compared these concentrations with those in specimens obtained from patients with noninfectious intermediate uveitis or cataract. RESULTS: Five mediators (interleukin [IL]-8, monocyte chemoattractant protein-1, tumor necrosis factor-alpha, IL-4, and IL-10) were detected in >50% of patients in all groups. In contrast, IL-5 and IL-12 were specific for ocular toxoplasmosis, and granulocyte monocyte colony-stimulating factor and IL-1 were specific for viral uveitis; these mediators could present specific markers for diagnostic purposes. Interferon-gamma, IL-6, and macrophage inflammatory protein-1beta were common markers of ocular toxoplasmosis and viral uveitis. IL-17 was a common marker of ocular toxoplasmosis and intermediate uveitis. CONCLUSIONS: We found specific cytokine profiles for each type of uveitis, with large interindividual variations and no etiological or clinical correlations. Ocular cytokine mapping contributes to a better understanding of the physiopathology of specific forms of uveitis and provides guidance for new targeted treatment.

Regulation of Toxoplasma gondii multiplication in BeWo trophoblast cells: cross-regulation of nitric oxide production and polyamine biosynthesis.

Materno-foetal transmission causes one of the most severe forms of infection with the protozoan parasite Toxoplasma gondii. Several studies have shown T. gondii in placental trophoblast cells, which form the barrier between maternal blood circulation and foetal tissue. Parasite multiplication in trophoblast cells is thus a critical step leading to infection of the foetus. Here, we show that multiplication of T. gondii tachyzoites was slow in BeWo trophoblast cells, compared with MRC-5 fibroblast cells. However, unlike MRC-5 cells, even combined stimulation with interferon-gamma and tumor necrosis factor-alpha did not reduce T. gondii replication in BeWo cells. This was associated with a lack of indoleamine-2,3-dioxygenase induction by these cytokines. Neither low availability of iron salts, nor an immunosuppressive action of cyclooxygenase-2 could be attributed to the low T. gondii multiplication rate in BeWo cells. However, treatment with the nitric oxide synthesis inhibitor N(G)-methyl-l-arginine and addition of ornithine enhanced the proliferation rate of the intracellular pathogen. Despite detection of inducible nitric oxide synthase-II mRNA in BeWo cells, nitric oxide production could not be detected during cell culture. Thus, inhibition of arginase activity by nitric oxide synthesis may be partially responsible for the lower multiplication rate in BeWo cells.

Usefulness of PCR analysis for diagnosis of alveolar echinococcosis with unusual localizations: two case studies.

The report presents two cases where diagnosis of alveolar echinococcosis was confirmed by Echinococcus multilocularis and Echinococcus granulosus PCR. The extrahepatic osseous involvement and the absence of initial hepatic involvement are unusual in both cases. Due to limitations of serological interpretation, PCR was useful to diagnose atypical echinococcosis.

Aspergillus galactomannan detection in the diagnosis of invasive aspergillosis in cancer patients.

PURPOSE: To assess the Aspergillus galactomannan enzyme-linked immunosorbent assay (ELISA) in the diagnosis of invasive aspergillosis (IA) in adult and pediatric oncohematologic patients. PATIENTS AND METHODS: The study was conducted in four patient groups: those with fever of unknown origin (FUO) during neutropenia, suspected pulmonary infection (PI), or nonpulmonary aspergillosis (NPA) and those undergoing surveillance (S) after hematopoietic stem-cell transplantation (HSCT). IA was classified as definite, probable, or possible, according to European Organization for Research and Treatment of Cancer/Mycosis Study Group definitions. RESULTS: A total of 3,294 serum samples were collected during 797 episodes (FUO, 261; PI, 297; NPA, 28; and surveillance, 211), and 153 episodes of IA were diagnosed (31 definite, 67 probable, and 55 possible). Three episodes were first suspected from galactomannan ELISA; the remaining 150 cases were diagnosed from clinical or radiologic evidence. Sensitivity of the ELISA was 64.5%, 16.4%, and 25.5% in definite, probable, and possible episodes of IA, respectively, and was lower in patients positive for anti-Aspergillus antibodies than in antibody-negative patients. Most false-positive results occurred in children and in allogeneic HSCT (allo-HSCT) patients. Overall specificity of the ELISA was 94.8%. It was lower in children compared with adults (P <.0001) and in allo-HSCT patients compared with non-allo-HSCT adults (P =.0002). Lowering the ELISA cutoff value from 1.500 to 0.700 seemed more relevant for non-allo-HSCT adults (sensitivity, 73.1%, 44.3%, and 44.7% in definite, probable, and possible IA, respectively; specificity, 94%). CONCLUSION: Galactomannan ELISA seems less sensitive than previously described, and sensitivity can be further reduced by the presence of anti-Aspergillus antibodies. A new cutoff value for the ELISA of 0.700 is proposed for non-allo-HSCT adults.