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Introduction. The imbalance of the immune response is an important factor contributing to the incidence of ocular toxoplasmosis (OT). Regulatory T cells (Treg) play a key role in maintaining the balance between Th1 and Th17 immune responses, while interleukin-27 (IL-27) levels are related to the differentiation of Th17 cells. This study analyzes the differences in the number of Treg cells and the level of IL-27 between OT patients and seropositive individuals without ocular lesions and its correlation with retinal lesion size. Methods. This analytic observational study, conducted for 8 months, involved 11 OT patients and 10 seropositive individuals without ocular lesions. All subjects underwent a comprehensive ophthalmological examination. Retinal lesions were documented by fundus photographs and the size was measured using Digimizer 4.2.2.0 software. Isolation of peripheral blood mononuclear cells (PBMC) was performed to measure the number of Treg cells using flow cytometry and interleukin-27 levels were assessed using the Sandwich enzyme-linked immunosorbent assay (ELISA) technique. Data were analyzed with SPSS. Result. The number of Treg cells in the OT group (47.16 ± 15.66%) was lower than in the seropositive group without the ocular lesions (62.86 ± 17.08%) (p = 0.029). The serum IL-27 levels in the OT group were not significantly different from the seropositive group without the ocular lesions (p = 0.360). The number of Treg cells was significantly related to retinal lesion size (p = 0.043), with a correlation coefficient of −0.648, indicating a strong and inverse correlation. There was no significant correlation between serum IL-27 levels and retinal lesion size (p = 0.556). Conclusion. Ocular toxoplasmosis patients have a low number of Treg cells that are inversely related to the retinal lesion size. The size of the retinal lesion increases as the number of Treg cells decreases. [ABSTRACT FROM AUTHOR]

Background: The innate immune response to tuberculosis infection may involve the increased production of nitric oxide and cathelicidin due to the up-regulated expression of the vitamin D receptor (VDR), though this proposed mechanism remains controversial. The aim of this study was to determine how the exposure of human monocytes to Mycobacterium tuberculosis (M. tuberculosis) DNA affects the production of nitric oxide and cathelicidin, as well as the expression of VDR. Methods: This study was performed using monocytes obtained from healthy donors. After 24 h incubation, monocytes were stimulated with M. tuberculosis DNA for 18 h to determine the expression of VDR mRNA and the production of nitric oxide and cathelicidin versus non-stimulated cells (the control group). Results: The expression of VDR mRNA was higher in the monocytes exposed to M. tuberculosis DNA compared to the control group (P = 0.020). Monocytes exposed to M. tuberculosis DNA also showed significantly increased production of nitric oxide and cathelicidin compared to the control group (P = 0.0001; P = 0.028). Conclusion: The stimulation of human monocytes with M. tuberculosis DNA increases the expression of the VDR mRNA and the production of nitric oxide and cathelicidin. [ABSTRACT FROM AUTHOR]

Background: Microscopic detection is the conventional method for detecting malaria parasites. Although it is efficient and inexpensive, it has its limitations. In recent years, polymeras chain reaction (PCR) has been considered superior to microscopy in detecting mixed Plasmodium infections or infections with low parasite density. To determine whether microscopic or nested PCR (nPCR) is better at detecting congenital malaria (CM). Methods: Blood smear examination and nPCR were performed with blood samples taken from mothers and their newborns, who were likely to be suffering from CM and in whom one of the symptoms was low birth weight (LBW). The sensitivity and specificity of each method were then compared. Results: During one year of study, the prevalence of CM among 92 LBW newborns was determined to be 6.8% using microscopy and 7.8% using nPCR. Among the 92 mother-infant paired subjects, CM was detected in 34 subjects (37%) by microscopy and in 39 subjects (42.4%) by nPCR. nPCR was more sensitive (76.5% vs 66.7%) but less specific (77.6% vs 84.9%) than microscopy. When the two methods were compared, nPCR gave significantly better results in diagnosing CM (AUC = 0.770; P < 0.001). Conclusion: Although microscopy remains the most appropriate method for the diagnosis of CM in remote areas, nPCR can be considered a complementary test. [ABSTRACT FROM AUTHOR]