HLA-DR binding prediction and experimental evaluation of T-cell epitopes of mycolyl transferase 85B [Ag85B], a major secreted antigen of mycobacterium tuberculosis

To identify T-cell epitopes of Ag85B by analysis of its sequence for prediction to bind HLA-DR alleles and evaluate the predicted peptides for recognition by T cells in antigen-induced proliferation assays. Materials/Subjects and The complete sequence of Ag85B was analyzed for HLA-DR binding prediction to 51 HLA-DR alleles by using a virtual matrix-based prediction program [ProPred]. Synthetic peptides covering the sequence of mature Ag85B were also analyzed for binding to HLA-DR alleles, and evaluated for recognition in antigen-induced proliferation assays with Ag85B-specific T-cell lines established from the peripheral blood mononuclear cells of 10 HLA-DR-heterogeneous tuberculosis patients. The ProPred analysis of the full-length Ag85B [325 aa], signal peptide [40 aa] and the mature protein [285 aa] predicted their binding to 100, 76 and 98% of the 51 HLA-DR alleles, respectively. The analysis of 31 synthetic peptides for binding to HLA-DR alleles showed that 4 of them could bind >50% HLA-DR alleles, and were considered promiscuous. Testing of Ag85B-specific T-cell lines with synthetic peptides showed that all of the T-cell lines responded to one or more peptides of Ag85B, and 9 of the 10 cell lines responded to one or more of the four peptides considered promiscuous for binding to HLA-DR alleles. The ProPred program was useful in predicting the HLA-DR alleles binding regions of Ag85B and identifying the promiscuous peptides recognized by T cells

Demographic pattern and clinical characteristics of patients with smear positive pulmonary tuberculosis in Kuwait

The aim of this study was to document various clinical factors that are likely to be of help in the control of tuberculosis in Kuwait. Details of patients with sputum positive for acid-fast bacilli in the period from January 1998 to December 2000 were collected retrospectively from the case records and population statistics from government sources. The data were then tabulated and analyzed. Of the 526 cases, 83.5% were expatriates and 16.5% Kuwaiti; 373 [70.9%] were male. Of the expatriates, 66.7% were from Asia and the Far East, 5.7% were >/= 60 years. The annual incidence was 8.34 per 100,000 population. The lowest incidence was observed in the Jahrah governorate with an overall incidence of 5 [2.0 among Kuwaitis and 6.4 among expatriates] per 100,000 population. The highest incidence overall [10.2] and among Kuwaitis [4.1] was observed in the Farwaniya governorate, while the highest incidence among expatriates was seen in the Capital governorate [13.4]. Radiologically, 94 [19.5%] had minimal, 246 [51.5%] had moderately advanced and 141 [29.3%] far-advanced disease. The majority of the patients [72%] had only + status for AFB in the smear. Hypercalcemia [25.7%], hyponatremia [22.15%] and hyperglycemia [29.9%] were common in the patients. Mean serum albumin was low [28.7 +/- 5.5 g/l]. Two hundred and forty-seven [47.2%] were declared cured while 116 [22.2%] completed treatment. Comparison between nationals and expatriates showed a significant difference only for age, smoking status, defaulter rate and place of residence. The lowest regional incidence was found in the Jahrah governorate. Both biochemical abnormalities and radiologically advanced presentations were common. Disease pattern and response to treatment was purely individual and did not differ with respect to nationality or race

Flexible fiberoptic bronchoscopy. Diagnostic yield

Fiberoptic bronchoscopy is a minimally invasive procedure with a high diagnostic yield. The aim of this study was to document the usefulness of the procedure in the diagnosis of various respiratory disorders in a Middle East country. Data on all bronchoscopies carried out in Chest Diseases Hospital, Kuwait from January 1996 to December 1998 were retrospectively collected. Out of 968 cases, only 620 [64%] patients had a full follow up. Suspected pulmonary tuberculosis [TB] [51.6%], unresolving pneumonia [16.1%], hemoptysis with a normal chest radiograph [8.4%], lung mass [7.7%] and hilar lymphadenopathy [3.2%] were the most common indications. Eleven% of patients who underwent bronchoscopy had a normal chest radiograph, the reason being hemoptysis in 75.4%, inhalation injury in 21.8% and suspected upper airway obstruction in 2.9%. In smear negative suspected TB cases, 22.5% proved to have active disease. Acid fast bacillus was identified in bronchoalveolar lavage, either by smear or culture, in 44 [73.3%] patients with suspected pulmonary TB and in 6 [54.5%] patients with miliary shadows. An underlying cause was identified in 28 [28%] patients with unresolving pneumonia. Ninety-four% of cases with clinical impression of bronchogenic carcinoma could be diagnosed. Transbronchial biopsy was diagnostic in 79% patients with diffuse parenchymal lung disease. No complications other than transient hypoxemia and controllable bleeding were noticed. Generally, the indications for flexible fiberoptic bronchoscopy remained similar to elsewhere. Unlike western series, the majority of the cases were for the diagnosis of pulmonary infections especially TB