Large sub-clonal variation in <i>Phytophthora infestans</i> from recent severe late blight epidemics in India

Abstract The population structure of the Phytophthora infestans populations that caused the recent 2013–14 late blight epidemic in eastern India (EI) and northeastern India (NEI) was examined. The data provide new baseline information for populations of P. infestans in India. A migrant European 13_A2 genotype was responsible for the 2013–14 epidemic, replacing the existing populations. Mutations have generated substantial sub-clonal variation with 24 multi-locus genotypes (MLGs) found, of which 19 were unique variants not yet reported elsewhere globally. Samples from West Bengal were the most diverse and grouped alongside MLGs found in Europe, the UK and from neighbouring Bangladesh but were not linked directly to most samples from south India. The pathogen population was broadly more aggressive on potato than on tomato and resistant to the fungicide metalaxyl. Pathogen population diversity was higher in regions around the international borders with Bangladesh and Nepal. Overall, the multiple shared MLGs suggested genetic contributions from UK and Europe in addition to a sub-structure based on the geographical location within India. Our data indicate the need for improved phytosanitary procedures and continuous surveillance to prevent the further introduction of aggressive lineages of P. infestans into the country

Purinergic signalling and immune cells

This review article provides a historical perspective on the role of purinergic signalling in the regulation of various subsets of immune cells from early discoveries to current understanding. It is now recognised that adenosine 5'-triphosphate (ATP) and other nucleotides are released from cells following stress or injury. They can act on virtually all subsets of immune cells through a spectrum of P2X ligand-gated ion channels and G protein-coupled P2Y receptors. Furthermore, ATP is rapidly degraded into adenosine by ectonucleotidases such as CD39 and CD73, and adenosine exerts additional regulatory effects through its own receptors. The resulting effect ranges from stimulation to tolerance depending on the amount and time courses of nucleotides released, and the balance between ATP and adenosine. This review identifies the various receptors involved in the different subsets of immune cells and their effects on the function of these cells

Follicular fluid dehydroepiandrosterone sulfate is a credible marker of oocyte maturity and pregnancy outcome in conventional in vitro fertilization cycles

Aim: To investigate if the level of dehydroepiandrosterone sulfate (DHEA-s) in follicular fluid (FF) influences the competence of oocytes to fertilize, develop to the blastocyst stage, and produce a viable pregnancy in conventional in vitro fertilization (IVF) cycles. Settings and Design: Prospective study of age-matched, nonpolycystic ovary syndrome (PCOS) women undergoing antagonist stimulation protocol involving conventional insemination and day 5 blastocyst transfer. Materials and Methods: FF levels of DHEA-s and E2 were measured by a radio-immuno-assay method using diagnostic kits. Fertilization rate, embryo development to the blastocyst stage and live birth rate were main outcome measures. Cycles were divided into pregnant/nonpregnant groups and also into low/medium/high FF DHEA-s groups. Statistical analysis was done by GraphPad Prism V software. Results: FF DHEA-s levels were significantly higher in pregnant (n = 111) compared to nonpregnant (n = 381) group (1599 ± 77.45 vs. 1372 ± 40.47 ng/ml; P = 0.01). High (n = 134) FF DHEA-s group had significantly higher percentage of metaphase II (MII) oocytes (91.5 vs. 85.54 vs. 79.44%, P < 0.0001), fertilization rate (78.86 vs. 74.16 vs. 71.26%, P < 0.0001), cleavage rate (83.67 vs. 69.1 vs. 66.17%, P = 0.0002), blastocyst formation rate (37.15 vs. 33.01 vs. 26.95%, P < 0.0001), and live birth rate (29.85 vs. 22.22 vs. 14.78%, P = 0.017) compared to medium (n = 243) and low (n = 115) FF DHEA-s groups, respectively despite comparable number of oocytes retrieved and number of blastocysts transferred. FF DHEA-s levels correlated significantly with the attainment of MII oocytes (Pearson r = 0.41) and fertilization rates (Pearson r = 0.35). Conclusion: FF DHEA-s level influences the oocyte maturation process and is predictive of fertilization, embryo development to the blastocyst stage and live birth rates in non-PCOS women undergoing conventional IVF cycles

Follicular fluid insulin like growth factor-1 (FF IGF-1) is a biochemical marker of embryo quality and implantation rates in in vitro fertilization cycles

Context: Insulin-like growth factor-1 (IGF-1) has been reported to play a role in human follicular and embryonic development. However, earlier studies carried out mostly in animal models or in culture mediums supplemented with IGF-1 have been unable to directly link IGF-1 with embryo quality. Results correlating IGF-1 with pregnancy outcome have also been ambiguous so far. Aim: The aim of this study is to find if in situ follicular-fluid level of IGF-1 is predictive of embryo quality and implantation rates in in vitro fertilization (IVF) cycles. Settings and Design: Prospective study involving 120 cycles of conventional IVF-embryo transfer in infertile women. Subjects and Methods: IGF-1 concentrations were estimated in pooled follicular-fluid on the day of oocyte-pickup. Embryo quality was assessed daily at different developmental stages. Cycles were sorted into low and high follicular fluid insulin-like growth factor-1 (FF IGF-1) groups according to the median value of measurement. Embryo quality, clinical pregnancy and implantation rate were the main outcome measures. Statistical Analysis: Graph-pad Prism 5 statistical package. Results: FF IGF-1 correlates with embryo quality (Pearson r = 0.3894, r2 = 0.1516, P 58.50 ng/mg protein (receiver operating characteristics AUC : 0.85 ± 0.03, 95% CI: 0.78-0.91). Conclusion: FF IGF-1 is a plausible biochemical marker of embryo quality and implantation rate and correlates with clinical pregnancy rates in conventional IVF cycles

Kv1.3 Channels Mark Functionally Competent CD8 + Tumor-Infiltrating Lymphocytes in Head and Neck Cancer

Tumor infiltrating lymphocytes (TILs) are potent mediators of an anti-tumor response. However, their function is attenuated in solid tumors. CD8(+) T cell effector functions such as cytokine and granzyme production depend on cytoplasmic Ca(2+), which is controlled by ion channels. In particular, Kv1.3 channels regulate the membrane potential and Ca(2+) influx in human effector memory T (T(EM)) cells. In this study, we assessed the contribution of reduced Kv1.3 and Ca(2+) flux on TIL effector function in head and neck cancer (HNC). We obtained tumor samples and matched peripheral blood from 14 patients with HNC. CD3(+) TILs were comprised of 57% CD4(+) (82% T(EM) and 20% T(reg)) and 36% CD8(+) cells. Electrophysiology revealed a 70% reduction in functional Kv1.3 channels in TILs as compared to peripheral blood T cells from paired patients, which was accompanied by a decrease in Ca(2+) influx. Immunofluorescence analysis showed that CD8(+) TILs expressing high Kv1.3 preferentially localized in the stroma. Importantly, high expression of Kv1.3 correlated with high Ki67 and granzyme B expression. Overall, these data indicate that defective Kv1.3 channels and Ca(2+) fluxes in TILs may contribute to reduced immune surveillance in HNC