Endothelial Nitric Oxide Synthase (eNOS) Gene Polymorphisms and Markers of Hemolysis, Inflammation and Endothelial Dysfunction in Brazilian Sickle Cell Anemia Patients

The impaired bioavailability of endogenous nitric oxide (NO) in sickle cell anemia (SCA) may be influenced by polymorphisms in the endothelial nitric oxide synthase gene (eNOS). We compared allelic/genotypic frequencies of the eNOS polymorphisms T-786C, VNTR4a/b and G894T between 89 adult SCA patients and 100 healthy controls, and investigated the relationship between these SNPs and markers of hemolysis [lactate dehydrogenase (LDH), indirect bilirubin (IB) and reticulocyte counts], inflammation [interleukins IL-1β, IL-6, IL-8, Tumor Necrosis Factor (TNF-α) and C-reactive protein (CRP)] and endothelial dysfunction (ED) [soluble vascular cell adhesion molecule-1 (sVCAM-1), soluble intercellular adhesion molecule-1 (sICAM-1), soluble L-selectin (sL-selectin), von Willebrand Factor (vWF) antigen and D-dimers] in the patients. The frequencies of the mutant -786C allele and -786C/C genotype were significantly higher in patients (p = 0.02 and p = 0.04, respectively) but not significantly correlated with the markers. For VNTR4a/b and G894T, the allelic/genotypic frequencies did not statistically differ between patient and control groups. Patients carrying the 4a allele and those with the 894G/G genotype showed a significant decrease in IB (p = 0.02 and p = 0.04, respectively), and only patients with the 4a allele exhibited reduced IL-1β (p = 0.01). The correlation profiles between markers of inflammation and ED significantly differed between patients carrying the mutant alleles and those with wild-type genotypes. This appears to be the first report on the relationship between eNOS gene polymorphisms and markers of hemolysis, inflammation and ED in Brazilian SCA patients. Our results indicate that the SNPs analyzed may influence the phenotypic variability of these patients.

Severe Paracoccidioidomycosis in a 14-Year-Old Boy

Paracoccidioidomycosis (PCM) is the most important systemic mycoses in Latin America. We describe a severe case of paracoccidioidomycosis in a 14-year-old boy, with a rapid disease progression. The fungal strain was isolated and inoculated into a T and/or B cell immunocompromised mice, which revealed a highly virulent strain. The case report presented herein emphasizes the importance of considering PCM in the differential diagnosis of patients with other infectious diseases in endemic areas and highlights a novel isolate.

Expression of activation and cytotoxic molecules by peripheral blood lymphocytes of patients with paracoccidioidomycosis

In a previous study, we reported an increased number of T CD8(+) cells in the bronchoalveolar lavage (BAL) of patients with pulmonary paracoccidioidomycosis, suggesting a role for these cells in the local immune response. The aims of this study were to verify, by flow cytometry, the activation state, as well as the production of cytotoxic molecules by peripheral blood lymphocytes (CD8(+) and CD4(+)). Specimens were obtained from patients with paracoccidioidomycosis (PCM), individuals with PCM-infection, i.e., healthy individuals with demonstrated strong cellular response against the fungus (PI) and controls, with studies conducted both ex-vivo and in vitro, after stimulation with Paracoccidioides brasiliensis yeast cells. The ex-vivo analysis demonstrated that PCM patients presented a lower frequency of granzyme A, B and perforin-positive cells, as compared to individuals with PCM infection (PI). P. brasiliensis stimulation led to a discrete increase in CD69(+) cells and a reduction in cytotoxic granule expression in all groups. The addition of IL-15 induced an increase in the frequency of CD69(+) cells only in PI individuals and controls. The effect of IL-15 on granzyme A and B expression was low, but a higher frequency of CD8(+) perforin(+) was detected in PI individuals than in patients with active PCM. IL-15Ralpha expression was lower in CD4(+) T cells from patients, in relation to the PI group. Furthermore, low levels of granulysin were detected in sera from PCM patients, but a tendency for an increase in these levels was observed after antifungal therapy. Taken together, these results indicate that lymphocytes from PCM patients are poorly activated, express low levels of IL-15Ralpha and produce basal levels of cytotoxic granules. These findings may account for the defective cytotoxic activity in patients and, consequently, a low capacity to kill the fungus.

Altered left ventricular diastolic function in subjects with spinal cord injury

STUDY DESIGN

This is cross-sectional study.

OBJECTIVES

The aim of this study is to investigate the cardiac structure and function of subjects with spinal cord injury (SCI) and the impact of metabolic, hemodynamic and inflammatory factors on these parameters.

SETTING

São Paulo, Brazil.

METHODS

Sixty-five nondiabetic, nonhypertensive, sedentary, nonsmoker men (34 with SCI and 31 healthy subjects) were evaluated by medical history, anthropometry, laboratory tests, analysis of hemodynamic and inflammatory parameters and echocardiography.

RESULTS

Subjects with SCI had lower systolic blood pressure and higher levels of C-reactive protein and tumor necrosis factor receptors than the healthy ones. Echocardiography data showed that the SCI group presented similar left ventricular (LV) structural and systolic parameters, but lower initial diastolic velocity (Em) (9.2 ± 0.5 vs 12.3 ± 0.5 cm s(-1); P<0.001) and higher peak early inflow velocity (E)/Em ratio (7.7 ± 0.5 vs 6.1 ± 0.3; P = 0.009) compared with the able-bodied group, even after adjustment for systolic blood pressure and C-reactive protein levels. Furthermore, injured subjects with E/Em >8 had lower peak spectral longitudinal contraction (Sm) (9.0 ± 0.7 vs 11.6 ± 0.4 cm s(-1); P<0.001) and cardiac output (4.2 ± 0.2 vs 5.0 ± 0.2 l min(-1); P = 0.029), as well as higher relative wall thickness (0.38 ± 0.01 vs 0.35 ± 0.01; P = 0.005), than individuals with SCI with E/Em<8, but similar age, body mass index, blood pressure, injury level, metabolic parameters and inflammatory marker levels.

CONCLUSION

Subjects with SCI presented impaired LV diastolic function in comparison with able-bodied ones. Moreover, worse LV diastolic function was associated with a pattern of LV concentric remodeling and subclinical decreases in systolic function among injured subjects. Overall, these findings might contribute to explain the increased cardiovascular risk reported for individuals with SCI.

Serum interleukin-18 and soluble tumour necrosis factor receptor 2 are associated with disease severity in patients with paracoccidioidomycosis

Interleukin (IL)-18 is a proinflammatory cytokine of the IL-1 superfamily that exhibits broad functional effects in innate and acquired immune responses and which has been found in high levels in several chronic inflammatory and autoimmune diseases. Over-expression of IL-18 may promote early resolution of infection or could promote a detrimental exaggerated immune response. The aim of this study was to determine serum levels of IL-18 and other inflammatory mediators [IL-12, soluble intercellular adhesion molecule 1 (sICAM-1), soluble tumour necrosis factor receptor 1 (TNF-RI), sTNF-RII, CXC chemokine ligand 9 (CXCL9), CXCL10] at baseline and after anti-fungal therapy in serum from patients with juvenile (JF) and adult (AF) forms of paracoccidioidomycosis (PCM), as well as in healthy controls (C), and to assess their possible relationships to the severity of disease. IL-18 and sTNF-RII levels in patients with the JF of PCM were significantly higher than those in the AF and controls. In relation to sICAM-1, no difference was observed between JF and AF patients but both presented higher levels than controls. sTNF-RI levels were higher in patients with PCM than in controls, and significantly higher concentrations were detected in AF patients compared to JF patients. Moreover, IL-12 and chemokines CXCL9 and CXCL10 were also higher in patients than in controls. In JF patients IL-18 levels correlated significantly with sICAM-1 (r=0 x 62, P<0 x 0001), sTNF-RI (r=0 x 63, P<0 x 0001), sTNF-RII (r=0 x 51, P=0 x 02), as well as with clinical severity. The results suggest the value of serum IL-18 and sTNF-Rs levels as a parameter of PCM severity and may support a possible role for them in the pathogenesis of the disease.

ICAM-1 is Overexpressed by Villous Trophoblasts in Placentitis

Although an in vitro study has hypothesized that expression of ICAM-1 by villous trophoblasts could be important for the influx of maternal immune cells in villitis, it remains to be shown whether the same phenomenon occurs in human villitis. To investigate the expression of ICAM-1 by villous trophoblasts, its relationship with rupture of the trophoblastic barrier and influx of immune cells into the villi, we analysed 18 paraffin-embedded placentas with placentitis (5 by Toxoplasma gondii, 3 by Trypanosoma cruzi, 2 by Paracoccidioides brasiliensis and 8 of unknown aetiology - VUE) and 8 control placentas for detection of ICAM-1 by immunohistochemistry. All cases but one of placentitis showed trophoblast overexpression of ICAM-1 in the inflamed villi, located almost exclusively next to the areas of trophoblastic rupture. The villitis cases (caused by T. cruzi, T. gondii and VUE) presented leukocyte adherence in the areas of trophoblastic rupture. When the inflammatory reaction was situated in the intervillous space (placentitis by P. brasiliensis), in spite of the trophoblastic rupture and ICAM-1 overexpression there was no leukocyte influx into villi. None of the control placentas showed ICAM-1 expression by the trophoblast. We concluded that overexpression of ICAM-1 by villous trophoblasts occurs during placentitis characterized by accumulation of leukocytes in the villous or intervillous space and probably plays an important role in the rupture of the trophoblastic barrier. The influx of immune cells into the villi appears to be mediated by ICAM-1 but the location of the antigen within villous stroma is certainly a crucial factor for its occurrence.

Evaluation of bronchoalveolar cells in pulmonary paracoccidioidomycosis

To investigate the local immune response, the cellular infiltrate and cytokine levels were analysed in bronchoalveolar lavage (BAL) from patients with pulmonary paracoccidioidomycosis. The group consisted of 19 patients aged 34-65 yrs. The diagnosis was confirmed by demonstration of the fungus in the sputum or BAL fluid and by serological tests. Cytospin preparations showed an increased number of lymphocytes and neutrophils in BAL. A higher number of CD8+ lymphocytes were observed in BAL compared with peripheral blood. Alveolar macrophages (AM) expressed approximately three-fold more major histocompatibility class II, intercellular adhesion molecule-1 and B7-2 molecules on their surfaces than their circulating counterparts, indicating that they had differentiated into activated macrophages inside the lungs. Cultured AM produced higher levels of interleukin (IL)-6, tumour necrosis factor (TNF)-alpha and macrophage inflammatory protein (MIP)-1alpha than peripheral blood monocytes. BAL fluid contained low but detectable amounts of IL-6, TNF-alpha and MIP-1alpha, and specific antibodies to Paracoccidioides brasiliensis, mainly of the immunoglobulin G2 isotype. As macrophage inflammatory protein-1alpha was shown to selectively attract CD8+ T-cells and this population was elevated in bronchoalveolar lavage, the data suggest that, besides macrophages, CD8+ T-cells may have an important role in the pathogenesis of pulmonary paracoccidioidomycosis.

Immunocytochemical localization of cytokines and inducible nitric oxide synthase (iNOS) in oral mucosa and lymph nodes of patients with paracoccidioidomycosis

Paracoccidioidomycosis (PCM) is a deep mycosis caused by Paracoccidioides brasiliensis, with high incidence in Brazil. In order to examine the immune response in lesional tissue from patients with PCM, we analyzed cytokines as well as the phenotype of the cell infiltrate. Paraffin-embedded tissue from the oral mucosa of eight patients with the localized adult form (AF) of PCM and from the lymph nodes of 10 patients with the juvenile form (JF) of PCM was analyzed by immunohistochemistry to detect tumor necrosis factor-alpha (TNF-alpha), inducible nitric oxide synthase (iNOS), transforming growth factor-beta (TGF-beta) and interleukin-10 (IL-10). Most of the inflammatory cells in the lymph nodes were CD68+ (macrophages, epithelioid and giant cells), while a mixed infiltrate with macrophages, plasma cells and neutrophils was detected in the oral mucosa. TNF-alpha as well as iNOS expression was similar in lymph nodes and oral mucosa, whereas TGF-beta and IL-10 were observed in a larger number of macrophages, epithelioid and giant cells in the lymph nodes, where numerous yeast cells were visualized. The higher expression of anti-inflammatory cytokines (IL-10 and TGF-beta) in lesions of patients with the JF of PCM (lymph nodes) may represent a mechanism by which the fungus evades the host immune response, contributing to a more severe and disseminated form of the disease.

Enhanced production of specific IgG4, IgE, IgA and TGF-beta in sera from patients with the juvenile form of paracoccidioidomycosis

Paracoccidioidomycosis (PCM) occurs in two distinct forms, the acute or juvenile form (JF), and the chronic or adult form (AF). To clarify the basis of this dichotomy, specific IgG subclasses, IgA and IgE anti-gp43 were measured by enzyme-linked immunosorbent assay, in patients with different forms of PCM. Serum levels of tumor necrosis factor-alpha, interleukin (IL)-6, IL-8, macrophage inflammatory protein (MIP)-1alpha and transforming growth factor (TGF)-beta were also quantified. We show here that JF patients have significantly higher titers of IgE antibodies against gp43, an immunodominant antigen specific for Paracoccidioides brasiliensis, than do patients with the unifocal adult form (UF-AF, isolated lesions). Patients with the multifocal adult form (MF-AF, lesions in more than one organ) also produced elevated levels of anti-P. brasiliensis IgE. Furthermore, specific IgE levels were correlated with IgG4, IgA and eosinophilia. Patients with JF showed eosinophilia and increased levels of TGF-beta, a switching factor for IgA. These results indicate a T helper (Th)-2 pattern of cytokine expression in both the JF and the MF-AF of PCM. On the other hand, patients with UF-AF had a significantly lower production of specific IgE, IgG4 and IgA than was seen in the other patient groups.