T lymphocyte activation profiles in peripheral blood of long- versus short-term residents of Kuwait: comparison with asthmatics.

INTRODUCTION: During the Arabian Gulf Wars of 1991 and 2003, the resident population of Kuwait sustained heavy exposure to environmental toxicants introduced by military activities. No comprehensive studies have been conducted to assess how exposure to the wartime and postwar environment may have altered the fundamental patterns of immune reactivity among Kuwaitis in ways that affect pathogenesis of disease. This present study addresses this issue by characterising immunological features of asthma and allergies in a Kuwaiti population that is unique and possibly correlates with toxicant exposures. MATERIALS AND METHODS: Twenty-fi ve long-term residents of Kuwait afflicted with bronchial asthma concurrent with rhinitis; and 2 healthy control groups: 18 long-term residents and 10 newcomers to Kuwait were evaluated by 2- and 3-colour fl ow cytometry for peripheral blood T cell subpopulation frequencies. RESULTS: Relative to healthy, long-term residents, significantly elevated frequencies of all activated cell phenotypes were observed in the blood of the asthmatic group (P <0.05 to P <0.001), except for CD8+HLA-DR+ cells and a presumed T-regulatory (Treg) subpopulation: CD4+CD25(high). The asthmatic group was also observed to have larger populations of CD3+ (pan-T cells), CD4+ (T helper cells) and CD8+ (cytotoxic T cells), CD3+CD56 (NKT-like cells) and CD56+CD16+ (NK cells) compared to healthy long-term residents. Compared to healthy recent immigrants, the blood of long-term residents contained elevated levels of CD3+CD56+ (NK-like), CD4+CD45RA+/ CD45RO+ (Naive-to-Memory Transitional), but lower CD4+CD25+(high) (Treg) (P <0.05). CONCLUSIONS: Elevated representation of natural killer (NKT)-like and memory phenotypes may predispose long-term residents towards enhanced susceptibility for airway disease; while at the same time, reducing representation of Treg cells which are protective against airway disease, and this may increase vulnerability to these syndromes among the residents of Kuwait. These results may provide insight into the features of immunopathogenesis of asthma and allergies in Kuwait that arise as a result of the special environment of the country.

Whole-blood polymerase chain reaction and restriction fragment length polymorphism: a simplified method by microwave irradiation.

OBJECTIVES: The aim of the present study was to develop a simple, quick and cheap method to process whole-blood samples for the molecular techniques polymerase chain reaction (PCR) and restriction fragment length polymorphism (RFLP) without the use of expensive reagents or sophisticated machines. MATERIALS AND METHODS: Venous whole-blood samples were collected from 40 individuals. The samples were frozen at -80 degrees C, and then rapidly thawed at 37 degrees C. Each sample was incubated with distilled water, then boiled in a microwave and centrifuged. The supernatant was taken directly for PCR and RFLP. For comparison, PCR and RFLP were performed on DNA purified from the same samples using the phenol-chloroform method and two commercial DNA extraction kits. RESULTS: PCR/RFLP results using the presented method were qualitatively similar to those obtained by DNA extracted using the other three methods. CONCLUSION: The presented method proved to be a simpler and cheaper way of processing whole-blood samples for PCR and RFLP analyses.

Screening methods used to determine the anti-microbial properties of Aloe vera inner gel.

The emergence of antibiotic resistant bacterial strains is a growing problem and is an important concern for patients, physicians, healthcare managers, and policymakers as it results in poorer health and economic outcomes. This has led to an urgent global call for new antimicrobial drugs, particularly from natural resources. We have been studying the antimicrobial properties of the inner leaf gel component of Aloe barbadensis Miller and have used a number of different, simple in vitro assays to establish a scientific basis for the potential use of Aloe vera on a range of clinically relevant bacteria. The bacteria used include Shigella flexneri, Methicillin-Resistant Staphylococcus aureus (MRSA), Enterobacter cloacae and Enterococcus bovis. In this paper, we compare standard methods recommended by the Clinical and Laboratory Standards Institute (CLSI) with a microtitre assay using a metabolic colour indicator Alamar blue. All the techniques described have shown that Aloe vera has an antimicrobial effect, however, the microtitre assay enables high throughput screening, under similar conditions and is less wasteful of plant material.

The inner gel component of Aloe vera suppresses bacterial-induced pro-inflammatory cytokines from human immune cells.

The present study was carried out to examine the anti-inflammatory activity of the inner leaf gel component of Aloe barbadensis Miller. A simple in vitro assay was designed to determine the effect of the inner gel on bacterial-induced pro-inflammatory cytokine production, namely TNF-alpha and IL-1 beta, from peripheral blood leukocytes stimulated with Shigella flexneri or LPS. This report describes the suppression of both cytokines with a freeze-dried inner gel powder and a commercial health drink from the same source. Comparison was made with a human monocytic cell-line (THP-1 cells) and a similar trend in responses was demonstrated.