Mastomys natalensis Has a Cellular Immune Response Profile Distinct from Laboratory Mice

The multimammate mouse (Mastomys natalensis; M. natalensis) has been identified as a major reservoir for multiple human pathogens including Lassa virus (LASV), Leishmania spp., Yersinia spp., and Borrelia spp. Although M. natalensis are related to well-characterized mouse and rat species commonly used in laboratory models, there is an absence of established assays and reagents to study the host immune responses of M. natalensis. As a result, there are major limitations to our understanding of immunopathology and mechanisms of immunological pathogen control in this increasingly important rodent species. In the current study, a large panel of commercially available rodent reagents were screened to identify their cross-reactivity with M. natalensis. Using these reagents, ex vivo assays were established and optimized to evaluate lymphocyte proliferation and cytokine production by M. natalensis lymphocytes. In contrast to C57BL/6J mice, lymphocytes from M. natalensis were relatively non-responsive to common stimuli such as phytohaemagglutinin P and lipopolysaccharide. However, they readily responded to concanavalin A stimulation as indicated by proliferation and cytokine production. In summary, we describe lymphoproliferative and cytokine assays demonstrating that the cellular immune responses in M. natalensis to commonly used mitogens differ from a laboratory-bred mouse strain.</jats:p

Association of Methylentetraydrofolate Reductase (MTHFR) 677 C > T gene polymorphism and homocysteine levels in psoriasis vulgaris patients from Malaysia: a case-control study

<p>Abstract</p> <p>Background</p> <p>The methylenetetrahydrofolate reductase (MTHFR) enzyme catalyzes the reduction of 5, 10-methylenetetrahydrofolate to 5-methyltetrahydrofolate and methyl donors. The methyl donors are required for the conversion of homocysteine to methionine. Mutation of MTHFR 677 C > T disrupts its thermostability therefore leads to defective enzyme activities and dysregulation of homocysteine levels.</p> <p>Methods</p> <p>This case-control study (n = 367) was conducted to investigate the correlation of the MTHFR gene polymorphism [NM_005957] and psoriasis vulgaris amongst the Malaysian population. Overnight fasting blood samples were collected from a subgroup of consented psoriasis vulgaris patients and matched controls (n = 84) for the quantification of homocysteine, vitamin B₁₂and folic acid levels.</p> <p>Results</p> <p>There was no significant increase of the MTHFR 677 C > T mutation in patients with psoriasis vulgaris compared with controls (<it>χ</it>²= 0.733, p = 0.392). No significant association between homocysteine levels and MTHFR gene polymorphism in cases and controls were observed (F = 0.91, df = 3, 80, p = 0.44). However, homocysteine levels in cases were negatively correlated with vitamin B₁₂(r = -0.173) and folic acid (r = -0.345) levels. Vitamin B₁₂and folic acid levels in cases were also negatively correlated (r = -0.164).</p> <p>Conclusions</p> <p>Our results indicate that there was no significant association between the MTHFR gene polymorphism and psoriasis vulgaris in the Malaysian population. There was no significant increase of the plasma homocysteine level in the psoriasis patients compared to the controls.</p

Nucleo-cytoplasmic transport of proteins and RNA in plants

Merkle T. Nucleo-cytoplasmic transport of proteins and RNA in plants. Plant Cell Reports. 2011;30(2):153-176.Transport of macromolecules between the nucleus and the cytoplasm is an essential necessity in eukaryotic cells, since the nuclear envelope separates transcription from translation. In the past few years, an increasing number of components of the plant nuclear transport machinery have been characterised. This progress, although far from being completed, confirmed that the general characteristics of nuclear transport are conserved between plants and other organisms. However, plant-specific components were also identified. Interestingly, several mutants in genes encoding components of the plant nuclear transport machinery were investigated, revealing differential sensitivity of plant-specific pathways to impaired nuclear transport. These findings attracted attention towards plant-specific cargoes that are transported over the nuclear envelope, unravelling connections between nuclear transport and components of signalling and developmental pathways. The current state of research in plants is summarised in comparison to yeast and vertebrate systems, and special emphasis is given to plant nuclear transport mutants