Hydrogel nanoparticle encapsulated plasmid as a suitable gene delivery system.

To facilitate the delivery of genetic material, the use of appropriate carriers such as polymers is necessary. Nanoparticles comprising of chitosan-alginate polymers were formed through pregel preparation method. Chi/Alg nanoparticles had a mean Z-Average diameter of 161.8 nm and mean zeta 29.3 mV, respectively. The ability of plasmidcomplex in preventing DNA migration showed Chi/Alg nanoparticles have great capacity to maintain plasmid. The efficiency of nanoparticles for transfection of pEGFP-N1 plasmid in the cultured HEK 293 cells was measured by flow cytometry. Cell viability assays indicated that nanoparticles had no toxic effect on HEK 293 cells after 4 or 24 h. Our suitable candidate for gene delivery would be Alg/Chi nanoparticles.

Distinct strains of Leishmania major induce different cytokine mRNA expression in draining lymph node of BALB/c mice.

Four genotypically distinct strains of L. major collected from persons residing in different endemic areas of cutaneous leishmaniasis in Iran were evaluated in BALB/c mice. Parasite virulence was evaluated by measuring the parasite burden in the lymph nodes. Immunogenicity of the strains was assessed by analysis of cytokines mRNA expression levels in popliteal lymph nodes of the mice in early (3, 16, 40 h) and late (week 1, W3, W5 and W8) time periods after infection. The expression of cytokines mRNA, namely Ifng, Il2,Il4,Il10 and Il12, was quantitated by real-time PCR. The lowest and the highest parasite loads were induced by Damghan (2·15 × 107) and Shiraz (9·59 × 109) strains, respectively. Moreover, Damghan strain elicited higher expression levels of Ifng and Il2 mRNA and the highest ratio of Ifng/Il4 mRNA expression compared with the other strains at 40 h and 8 weeks post-infection. The results indicate that the inoculation of BALB/c mice with different strains induced high diversity in parasite burden and cytokines gene expression. Amongst the four strains, Damghan strain showed the lowest parasite load and the highest tendency to induce expression of Th1 cytokines gene and might be considered as a safe and immunogenic strain.

Cloning, Expression and Characterization of Zebra Fish Ferroportin in Hek 293T Cell Line.

BACKGROUND: Ferroportin (Fpn), a regulator of iron homeostasis is a conserved membrane protein that exports iron across the enterocytes, macrophages and hepatocytes into the blood circulation. Fpn has also critical influence on survival of microorganisms whose growth is dependent upon iron, thus preparation of Fpn is needed to study the role of iron in immunity and pathogenesis of micoorganisms. METHODS: To prepare and characterize a recombinant ferroportin, total RNA was extracted from Indian zebrafish duodenum, and used to synthesize cDNA by RT-PCR. PCR product was first cloned in Topo TA vector and then subcloned into the GFP expression vector pEGFP-N1. The final resulted plasmid (pEGFP-ZFpn) was used for expression of Fpn-EGFP protein in Hek 293T cells. RESULTS: The expression was confirmed by appearance of fluorescence in Hek 293 T cells. Recombinant Fpn was further characterized by submission of its predicted amino acid sequences to the TMHMM V2.0 prediction server (hidden Markov model), NetOGlyc 3.1 and NetNGlyc 3.1 servers. The obtained Fpn from indian zebrafish also contained eight transmembrane domains with N- and C-termini inside the cytoplasm and harboured 78 O-glycosylated amino acids. CONCLUSION: The recombinant Fpn from Indian zebra fish was successfully expressed in Hek 293 cell line. Although the discrepancy in two amino acids was observed in our produced Fpn and resulted in an additional O-glycosylation site, but had no effect on the topology of the protein compared to other Fpn described by other researchers. Therefore this construct can be used in future iron studies.

Soluble CD26/CD30 levels in visceral leishmaniasis: markers of disease activity.

Leishmania infantum is the causative agent of zoonotic visceral leishmaniasis (VL). If untreated the disease could be fatal; however, in some cases the infection can run a subclinical course. In subclinical infections a Th1-response predominates, while Th2-responses and/or probably Treg cells are related to unfavourable outcome of the disease in active VL. In the present study we determined the levels of soluble (s) CD26 and CD30 co-stimulatory molecules in sera from patients with active VL, asymptomatic individuals and healthy volunteers. Results showed a significant difference in both sCD26 and sCD30 between infected cases and normal individuals (P < or = 0.001). However, there was no significant difference in sCD26 levels between asymptomatic cases and patients, although the difference was not significant. sCD30 levels were significantly higher in VL patients than asymptomatic cases (P < or = 0.001). These findings suggest a possible association between sCD26 and sCD30 levels and the clinical manifestation of L. infantum infection.