Decreased level of antibodies and cardiac involvement in patients with chronic Chagas heart disease vaccinated with BCG

Studies indicate that Trypanosoma cruzi is capable of inducing immunological disturbances such as decreased expression of molecules involved in T-cell survival and costimulation for antigen-driven T-cell responses. On the other hand, several reports have described that BCG vaccination induces a T-helper 1-type immune response with protective effects in different pathologies. In this regard, we evaluated whether BCG vaccination coexists with a better clinical and immunological profile of chronic Chagas heart disease (CCHD). We performed a cross-sectional study in T. cruzi seropositive patients categorized according the BCG vaccine background and to the well-established CCHD classification provided by Storino et al. All individuals were subjected to a complete clinical examination. All patients presented detectable levels of autoantibodies anti-p2β, anti-B13, anti-FRA and antiparasite homogenate immunoglobulins, which were unrelated to age and sex distribution or blood pressure values. Comparisons according to BCG vaccination revealed that individuals who had not been vaccinated presented higher values of antibodies, and patients without BCG vaccine had an OR of 6.1 (95 % CI 1.23?29.25, p = 0.02) for globally dilated cardiomyopathy with reduced ejection fraction (Hosmer and Lemeshow test of 5.2 p = 0.73). Our results suggest that BCG vaccination coexists with a better clinical and immunological profile of CCHD, associated with lower cardiac involvement.Fil: Vicco, Miguel Hernán. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe; Argentina. Universidad Nacional del Litoral. Facultad de Bioquímica y Ciencias Biológicas; Argentina. Provincia de Santa Fe. Ministerio de Salud. Hospital J. B. Iturraspe; ArgentinaFil: Bontempi, Iván. Universidad Nacional del Litoral. Facultad de Bioquímica y Ciencias Biológicas; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe; ArgentinaFil: Rodeles, Luz. Provincia de Santa Fe. Ministerio de Salud. Hospital J. B. Iturraspe; ArgentinaFil: Yodice, Agustina. Provincia de Santa Fe. Ministerio de Salud. Hospital J. B. Iturraspe; ArgentinaFil: Marcipar, Iván Sergio. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe; Argentina. Universidad Nacional del Litoral. Facultad de Bioquímica y Ciencias Biológicas; ArgentinaFil: Bottasso, Oscar Adelmo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Rosario. Instituto de Inmunología Clinica y Experimental de Rosario. Universidad Nacional de Rosario. Facultad de Ciencias Médicas. Instituto de Inmunología Clinica y Experimental de Rosario; Argentin

Altered distribution of peripheral blood memory B cells in humans chronically infected with Trypanosoma cruzi.

Numerous abnormalities of the peripheral blood T cell compartment have been reported in human chronic Trypanosoma cruzi infection and related to prolonged antigenic stimulation by persisting parasites. Herein, we measured circulating lymphocytes of various phenotypes based on the differential expression of CD19, CD4, CD27, CD10, IgD, IgM, IgG and CD138 in a total of 48 T. cruzi-infected individuals and 24 healthy controls. Infected individuals had decreased frequencies of CD19+CD27+ cells, which positively correlated with the frequencies of CD4+CD27+ cells. The contraction of CD19+CD27+ cells was comprised of IgG+IgD-, IgM+IgD- and isotype switched IgM-IgD- memory B cells, CD19+CD10+CD27+ B cell precursors and terminally differentiated CD19+CD27+CD138+ plasma cells. Conversely, infected individuals had increased proportions of CD19+IgG+CD27-IgD- memory and CD19+IgM+CD27-IgD+ transitional/naïve B cells. These observations prompted us to assess soluble CD27, a molecule generated by the cleavage of membrane-bound CD27 and used to monitor systemic immune activation. Elevated levels of serum soluble CD27 were observed in infected individuals with Chagas cardiomyopathy, indicating its potentiality as an immunological marker for disease progression in endemic areas. In conclusion, our results demonstrate that chronic T. cruzi infection alters the distribution of various peripheral blood B cell subsets, probably related to the CD4+ T cell deregulation process provoked by the parasite in humans