Novel non-viral method for transfection of primary leukemia cells and cell lines

BACKGROUND: Tumor cells such as leukemia and lymphoma cells are possible targets for gene therapy. However, previously leukemia and lymphoma cells have been demonstrated to be resistant to most of non-viral gene transfer methods. METHODS: The aim of this study was to analyze various methods for transfection of primary leukemia cells and leukemia cell lines and to improve the efficiency of gene delivery. Here, we evaluated a novel electroporation based technique called nucleofection. This novel technique uses a combination of special electrical parameters and specific solutions to deliver the DNA directly to the cell nucleus under mild conditions. RESULTS: Using this technique for gene transfer up to 75% of primary cells derived from three acute myeloid leukemia (AML) patients and K562 cells were transfected with the green flourescent protein (GFP) reporter gene with low cytotoxicity. In addition, 49(+/- 9.7%) of HL60 leukemia cells showed expression of GFP. CONCLUSION: The non-viral transfection method described here may have an impact on the use of primary leukemia cells and leukemia cell lines in cancer gene therapy.     

Uremia causes premature ageing of the T cell compartment in end-stage renal disease patients

ABSTRACT: BACKGROUND: End-stage renal disease (ESRD) patients treated with renal replacement therapy (RRT) have premature immunologically aged T cells which may underlie uremia-associated immune dysfunction. The aim of this study was to investigate whether uremia was able to induce premature ageing of the T cell compartment. For this purpose, we examined the degree of premature immunological T cell ageing by examining the T cell differentiation status, thymic output via T cell receptor excision circle (TREC) content and proliferative history via relative telomere length in ESRD patients not on RRT. RESULTS: Compared to healthy controls, these patients already had a lower TREC content and an increased T cell differentiation accompanied by shorter telomeres. RRT was able to enhance CD8+ T cell differentiation and to reduce CD8+ T cell telomere length in young dialysis patients. An increased differentiation status of memory CD4+ T cells was also noted in young dialysis patients. CONCLUSION: Based on these results we can conclude that uremia already causes premature immunological ageing of the T cell system and RRT further increases immunological ageing of the CD8+ T cell compartment in particular in young ESRD patients.     

VariVis: a visualisation toolkit for variation databases

Background  

With the completion of the Human Genome Project and recent advancements in mutation detection technologies, the volume of data available on genetic variations has risen considerably. These data are stored in online variation databases and provide important clues to the cause of diseases and potential side effects or resistance to drugs. However, the data presentation techniques employed by most of these databases make them difficult to use and understand.     

Permethrin-impregnated bednet effects on resting and feeding behaviour of lymphatic filariasis vector mosquitoes in Kenya

The impact of permethrin-impregnated bednets on resting and feeding behaviour of mosquito vectors of Wuchereria bancrofti, causing human lymphatic filariasis was studied in six pairs of villages (treated and untreated) before and after intervention. The study villages were in Kwale District, near the coast of Kenya, where Bancroftian filariasis is highly endemic, transmitted by a combination of both anopheline and culicine mosquito vectors. Mosquitoes were collected weekly in each village, indoors (using pyrethrum spray catches) and outdoors (using pit traps) during 3–4 months following the long rainy season. Of the filariasis vector species of mosquitoes collected in 1994 before intervention, 33.6% were members of the Anopheles gambiae complex, 30% were An. funestus and 36.4% were Culex quinquefasciatus. PCR analysis of the An. gambiae complex species collected in 1995 demonstrated that 98.5% were An. gambiae sensu stricto, 1% An. arabiensis and 0.5% An. merus. Introduction of impregnated bednets in 1995 significantly reduced the number of indoor-resting An. gambiae s.l. by 94.6% and An. funestus by 96.7%, but there was no change in the number of Cx quinquefasciatus collected indoors. The number of outdoor-resting An. gambiae s.l. was significantly reduced, whereas densities of An. funestus and Cx quinquefasciatus remained unaffected outdoors. ELISA analysis of mosquito bloodmeals showed a shift from human to animal feeding after the introduction of treated nets. The human blood index (HBI) for indoor resting Cx quinquefasciatus was reduced from 93.1% to 14.4%. Vector potential based on the HBI and mosquito density was estimated to be reduced by 99% for An. gambiae s.l., 98% for An. funestus and 97% for Cx quinquefasciatus and vectorial capacity would be suppressed even more by the impact on the vector survival rates (not measured). These results suggest that permethrin-impregnated bednets give effective personal protection against transmission of W. bancrofti by An. gambiae, An. funestus and Cx quinquefasciatus in East Africa.     

Identification of proteins related to the stress response in <Emphasis Type="Italic">Enterococcus faecalis</Emphasis> V583 caused by bovine bile

Background  

Enterococcus faecalis is an opportunistic pathogen and one of the most important causes of hospital infections. Bile acids are a major stress factor bacteria have to cope with in order to colonize and survive in the gastro-intestinal tract. The aim of this study was to investigate the effects of bile acids on the intracellular proteome of E. faecalis V583.