Co-administration of IL-1+IL-6+TNF-α with Mycobacterium tuberculosis infected macrophages vaccine induces better protective T cell memory than BCG

BCG has been administered globally for more than 75 years, yet tuberculosis (TB) continues to kill more than 2 million people annually. Further, BCG protects childhood TB but is quite inefficient in adults. This indicates that BCG fails to induce long-term protection. Hence there is a need to explore alternative vaccination strategies that can stimulate enduring T cell memory response. Dendritic cell based vaccination has attained extensive popularity following their success in various malignancies. In our previous study, we have established a novel and unique vaccination strategy against Mycobacterium tuberculosis (M. tb) and Salmonella typhimurium by utilizing infected macrophages (IM). In short-term experiments (30 days), substantial degree of protection was observed. However, remarkable difference was not observed in long-term studies (240 days) due to failure of the vaccine to generate long-lasting memory T cells. Hence, in the present study we employed T cell memory augmenting cytokines IL-1+IL-6+TNF-α and IL-7+IL-15 for the induction of the enhancement of long-term protection by the vaccine. We co-administered the M. tb infected macrophages vaccine with IL-1+IL-6+TNF-α (IM-1.6.α) and IL-7+IL-15 (IM-7.15). The mice were then rested for a reasonably large period (240 days) to study the bona fide T cell memory response before exposing them to aerosolized M. tb. IM-1.6.α but not IM-7.15 significantly improved memory T cell response against M. tb, as evidenced by recall responses of memory T cells, expansion of both central as well as effector memory CD4 and CD8 T cell pools, elicitation of mainly Th1 memory response, reduction in the mycobacterial load and alleviated lung pathology. Importantly, the protection induced by IM-1.6.α was significantly better than BCG. Thus, this study demonstrates that not only antigen-pulsed DCs can be successfully employed as vaccines against cancer and infectious diseases but also macrophages infected with M. tb can be utilized with great efficacy especially in protection against TB.     

Normal rat kidney proximal tubule cells in primary and multiple subcultures

Summary Anin vitro model to establish primary and subcultures of rat kidney proximal tubule (RPT) cells is described. After excising the kidneys and separating the cortex, the cortical tissue is digested with the enzyme DNAse-collagenase (Type I) resulting in a high yield of viable RPT Cells. The isolated RPT cells are then seeded onto rat tail collagen-coated surfaces and grown to confluency in a serum-free, hormonally defined medium. The cell yield can be increased by transfering the conditioned medium on Day 1 to more rat tail collagen-coated surfaces. RPT cell attachment and morphology was better on rat tail collagen-coated surfaces than on bovine collagen Type I coated surfaces. The culture medium was a 1∶1 mixture of Ham’s F-12 and Dulbecco’s modified Eagle’s medium supplemented with bovine serum albumin, insulin, transferrin, selenium, hydrocortisone, triiodothyronine, epidermal growth factor, and glutamine. The RPT cells became confluent in 7–10 d, at which point they could be subcultured by trypsinizing and growth in the same medium. In some studies, 10 ng/ml cholera toxin was added to the culture medium. We could passage the RPT cells up to 14 times in the presence of cholera toxin. The cells were investigated for activity of several markers. The cells were histochemically positive for alkaline phosphatase and γ-glutamyl transpeptidase activity and synthesized the intermediate filament pankeratin. The RPT cells displayed apically directed sodium-dependent active glucose transport in culture. Hence, the RPT cells retain structural and functional characteristics of transporting renal epithelia in culture. This rat cell culture model will be a valuable tool for substrate uptake and nephrotoxicity studies.     

Novel intron length polymorphic (ILP) markers from starch biosynthesis genes reveal genetic relationships in Indian wheat varieties and related species

Molecular Biology Reports - Introns experience lesser selection pressure, thus are liable for higher polymorphism. Intron Length Polymorphic (ILP) markers designed from exon-flanking introns...     

A Study on Mutational Dynamics of Simple Sequence Repeats in Relation to Mismatch Repair System in Prokaryotic Genomes

Mutational bias toward expansion or contraction of simple sequence repeats (SSRs) is referred to as directionality of SSR evolution. In this communication, we report the mutational bias exhibited by mononucleotide SSRs occurring in the non-coding regions of several prokaryotic genomes. Our investigations revealed that the strains or species lacking mismatch repair (MMR) system generally show higher number of polymorphic SSRs than those species/strains having MMR system. An exception to this observation was seen in the mycobacterial genomes that are MMR deficient where only a few SSR tracts were seen with mutations. This low incidence of SSR mutations even in the MMR-deficient background could be attributed to the high fidelity of the DNA polymerases as a consequence of high generation time of the mycobacteria. MMR system-deficient species generally did not show any bias toward mononucleotide SSR expansions or contractions indicating a neutral evolution of SSRs in these species. The MMR-proficient species in which the observed mutations correspond to secondary mutations showed bias toward contraction of polymononucleotide tracts, perhaps, indicating low efficiency of MMR system to repair SSR-induced slippage errors on template strands. This bias toward deletion in the mononucleotide SSR tracts might be a probable reason behind scarcity for long poly A|T and G|C tracts in prokaryotic systems which are mostly MMR proficient. In conclusion, our study clearly demonstrates mutational dynamics of SSRs in relation to the presence/absence of MMR system in the prokaryotic system.     

Litter and soil biodiversity jointly drive ecosystem functions

The decomposition of litter and the supply of nutrients into and from the soil are two fundamental processes through which the above- and belowground world interact. Microbial biodiversity, and especially that of decomposers, plays a key role in these processes by helping litter decomposition. Yet the relative contribution of litter diversity and soil biodiversity in supporting multiple ecosystem services remains virtually unknown. Here we conducted a mesocosm experiment where leaf litter and soil biodiversity were manipulated to investigate their influence on plant productivity, litter decomposition, soil respiration, and enzymatic activity in the littersphere. We showed that both leaf litter diversity and soil microbial diversity (richness and community composition) independently contributed to explain multiple ecosystem functions. Fungal saprobes community composition was especially important for supporting ecosystem multifunctionality (EMF), plant production, litter decomposition, and activity of soil phosphatase when compared with bacteria or other fungal functional groups and litter species richness. Moreover, leaf litter diversity and soil microbial diversity exerted previously undescribed and significantly interactive effects on EMF and multiple individual ecosystem functions, such as litter decomposition and plant production. Together, our work provides experimental evidence supporting the independent and interactive roles of litter and belowground soil biodiversity to maintain ecosystem functions and multiple services.     

Unravelling the emerging threats of microplastics to agroecosystems

Reviews in Environmental Science and Bio/Technology - In the past few decades, pollution from microplastics has emerged as an important issue on a global scale. These plastic particles are mainly...     

Antioxidant and Antidiabetic Properties of Extracts from Three Underutilized Food Plants of North East India

Three underutilized leafy vegetables Sarcochlamys pulcherrima (Roxb.) Gaudich (SP), Ipomoea aquatica Forssk. (IA) and Zanthoxylum rhetsa (Roxb.) DC (ZR) were extracted with different solvents viz. 95 % ethyl alcohol, methanol and hot water. The extracts were evaluated for their antioxidant potential via DPPH, ABTS and FRAP assay along with electroanalytical studies using cyclic voltammetry. The antidiabetic potential was determined by recording their α-amylase and α-glucosidase inhibitory assay. The total phenolic content (TPC), total flavonoid content (TFC) and the liquid chromatography-mass spectrometry (LC/MS) based phytochemical profiles of the extracts were also determined. All three extracts of SP exhibited significant antioxidant capacity. The antidiabetic potential of the IA and ZR extracts was found to be higher than or at par with that of standard acarbose. LC/MS studies reveal the presence of hitherto reported antioxidant and antidiabetic compounds like gamma-aminobutyric acid, cinnamic acid, caffeic acid, α-viniferin, piperlonguminine, niacin, kaempferol, etc., in the extracts.     

Metastases suppressor NME2 associates with telomere ends and telomerase and reduces telomerase activity within cells

Analysis of chromatin-immunoprecipitation followed by sequencing (ChIP-seq) usually disregards sequence reads that do not map within binding positions (peaks). Using an unbiased approach, we analysed all reads, both that mapped and ones that were not included as part of peaks. ChIP-seq experiments were performed in human lung adenocarcinoma and fibrosarcoma cells for the metastasis suppressor non-metastatic 2 (NME2). Surprisingly, we identified sequence reads that uniquely represented human telomere ends in both cases. In vivo presence of NME2 at telomere ends was validated using independent methods and as further evidence we found intranuclear association of NME2 and the telomere repeat binding factor 2. Most remarkably, results demonstrate that NME2 associates with telomerase and reduces telomerase activity in vitro and in vivo, and sustained NME2 expression resulted in reduced telomere length in aggressive human cancer cells. Anti-metastatic function of NME2 has been demonstrated in human cancers, however, mechanisms are poorly understood. Together, findings reported here suggest a novel role for NME2 as a telomere binding protein that can alter telomerase function and telomere length. This presents an opportunity to investigate telomere-related interactions in metastasis suppression.