Leishmaniasis is considered as a zoonotic infection and neglected tropical disease.
Leishmania
treatment is not totally successful and imposes high expenditures, especially in developing countries. Since the natural infection leads to the robust immunity in most of the human cases, many bodies of research have been focusing on
Leishmania
vaccines, being capable to control
Leishmania
infection. First generation vaccines (such as Leishmune
®
and CaniLeish
®
) have proved robust protective immunity in dogs. In human, recombinant vaccines, including Leish-F1 could confer some degrees of protective immunity against natural infection. Recently, ChAd63-KH DNA vaccine has been accomplished in providing prevention against
Leishmania
infection; however, this vaccine should be further evaluated in other clinical trials.
Phlebotomus papatsi North Africa, the Middle East, central Asia and the Indian subcontinent L. tropica LCL Human Rock hyraxes Unknown animals P. sergenti North Africa, the Middle East, central Asia and the Indian subcontinent
Immunity to Leishmania is believed to be strongly dependent upon the activation of Th1 immune responses, although the exact role of cytotoxic T lymphocytes (CTLs) has not yet been determined. The aims of this study were to establish a suitable cytotoxicity assay to measure CTL activity and to compare immunity induced by Leishmania mexicana gp63 cDNA via i.m. injection and gene gun immunization in the BALB/c mouse model. The CTL activity was evaluated by short-term (51)Cr-release cytotoxicity assays against CT26 tumour cells transfected with L. mexicana gp63 cDNA and dendritic cells (DCs) loaded with soluble Leishmania antigen (SLA) as targets. The results clearly demonstrated that higher protection to L. mexicana infection was induced by gene gun DNA-immunization vs. i.m. injection. Cytotoxic T lymphocyte activity of splenocytes was observed in mice immunized either with L. mexicana gp63 cDNA or SLA and long-lived CTL activity was observed in immunized and/or re-challenged mice but not naïve mice infected with the parasite.
Cutaneous leishmaniasis (CL) heals spontaneously within several weeks or months, but, in rare cases, CL-active lesions last for many years. In this study, we assessed cell-mediated immunity in non-healing CL through the measurement of three pro-inflammatory cytokines: Interferon-γ (IFN-γ), IL-17a and CXCL-11. For this, 32 patients afflicted with healing or non-healing CL were recruited in this study. Peripheral blood mononuclear cells (PBMCs) of every patient were treated with three antigens: purified protein derivative (PPD), soluble Leishmania antigen (SLA) and phytohaemagglutinin (PHA). Cytokine quantification was performed using enzyme-linked immunosorbent assay (ELISA) method. Results of our study showed that neither cytokine produced in the presence of a PPD stimulator (as an irrelevant antigen) significantly differed between the healing and non-healing groups (P-value ≥0.05 for all of them). However, IFN-γ, CXCL-11 and IL-17a levels produced in the presence of PHA or SLA were significantly higher within the healing than in the non-healing group (P-value <0.01 for all of them). It seems that appropriate levels of IFN-γ, as well as IL-17a and CXCL-11, contribute to the control of Leishmania infection.
growth differentiation factor 9 (GDF9) is a fecundity major gene affecting prolificacy in sheep. In the present study, genetic variation of a 380-bp fragment in GDF9 gene exon 1 was investigated in 100 Lori ewes. Single-strand conformational polymorphism (SSCP) and DNA sequencing methods were used to detect single nucleotide polymorphism (SNP) of the studied fragment. A SNP (g.306G>A), known as G1 mutation, with two genotypes (GG and AG) was found in two different sscP patterns of GDF9 gene exon 1, deducing an amino acid (AA) exchange (p.Arg87His). Frequencies of the AG and GG genotypes were 37.65% and 62.35%, respectively. Also, the estimated allelic frequencies for the A and G alleles were 18.825% and 81.175%, respectively. The observed nucleotide sequences were subjected to alignment analysis and it was found that the studied fragment had more than 99.7% similarity with some sequences reported for other breeds of sheep. Two different secondary and 3D protein structures were predicted for A and G alleles. Moreover, the A and G alleles had different isoelectric pH values (8.7 and 9, respectively). The observed genotypes tended to have a significant association with litter size (P<0.10) where average litter size of GG ewes was slightly (20%) higher than for AG animals. With respect to the results of the present study, it seems that more studies are needed to evaluate the mutations in other fragments of this gene or other genes in Lori sheep.
Key words: GDF9, mutation, Pcr-sscP, bioinformatics analysis, sheepThe interest in evaluation and identification of major genes and their relationships with prolificacy in sheep has increased since 1980 (Davis, 2004). The sheep is considered as an ideal species for studying genes affecting reproduction and mechanisms controlling ovulation rate (Polley et al., 2010). Three fecundity genes have been identified in sheep. These three genes belong to a large family of TGFβ and are called BMPR-1B (bone morphogenetic protein receptor 1B), BMP15 (bone morphogenetic protein 15) and GDF9 (growth differentiation factor 9) which are located
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