Résumé
The human leukocyte antigens [HLA] are a group of cell surface molecules encoded for by the major histocompatability locus on the short arm of human chromosome six. Individuals carrying the HLA-B27 gene, have been shown to have a higher incidence of isolated acute anterior uveitis [AAU]. This study aims to examine the incidence of the HLAB27 gene in individuals presenting with AAU at GMCHRC. This pilot study was carried out for a period from May 2013 to July 2013 at GMCHRC Ajman UAE. Four patients of clinically diagnosed AAU were examined for the presence of the HLA B27 gene. Genomic DNA was amplified using primers and cycling parameters were as described by Bunce et al. using exon-2, B-locus- specific primers. The PCR products were run in a 1% agarose gel stained with ethidium bromide [0.5 microg/ml] and visualized under U.V. light. Four cases of AAU were subjects in this study. Of the four cases examined two [50%] were positive for the HLAB27 gene. The M:F ratio of the cases 3:1. All the HLAB27 positive cases were males. The average age of the positive cases was 37.5 years as compared to 53.5 years in the negative cases. There was no racial predisposition seen. Using the above set of primers, DNA from HLA B27 positive individuals gave a 150 bp band. AAU is the most common form of uveitis. Of the cases reported in literature half of all cases of AAU are HLA-B27 positive and this is similar to the results displayed in our series of four cases. Cases positive for HLAB27 in AAU require active treatment using immunomodulators for early resolution and topical cycloplegic agents and steroids are the cornerstones of treatment. Methotrexate, Salazopyrine, anti-TNF and anti-CD20 therapy may be used to prevent recurrent attacks. This study exemplifies the use of PCR and DNA diagnostics in the identification of HLAB27 gene in cases of AAU. Further studies using the Dideoxy Sequencing are proposed to be carried out
Résumé
Interleukin 12 [IL-12] is an important cytokine produced by monocytes and macrophages. It up regulates Th1 cytokines production especially IFNgamma and inhibits the expression of Th2 cytokines, so, its main function is the regulation of the bias of the immune system towards Th1 or Th2 response through a balance with IL-4 early in the immune response. This work was done to evaluate the serum and bronchoalveolar lavage [BAL] IL-12 in asthmatic patients compared with tuberculous patients and patients with primary lung cancer, to assess the impact of IL-12 on Th1-Th2 cytokines profile which determine the type of the response in these different diseases and to propose its potential clinical usefulness. The study included 4 groups: group I consisted of 20 asthmatic patients, group II: 10 patients who had pulmonary TB, group III: 10 patients with bronchogenic carcinoma, and group IV: 20 normal individuals. For all groups IL-12 was estimated in serum and [BAL] fluid using ELISA technique. Considering the results, IL-12 was significantly decreased in asthmatic patients and it increased with hyposensitiz ation, highly significantly increased in active pulmonary TB and significantly increased in localized bronchogenic carcinoma. It was concluded that IL-12 plays a central role on Th1-Th2 cytokines balance, being decreased in allergic conditions, i.e., producing immunological Th2, shift which is corrected to Th1 pathway by hyposensitization, hence, it may be of diagnostic and therapeutic values in bronchial asthma