Priyanka Banerjee

PROINFLAMMATORY CYTOKINES INDUCED ALTERED EXPRESSION OF CYCLOOXYGENASE-2 GENE RESULTS IN UNRECEPTIVE ENDOMETRIUM IN WOMEN WITH IDIOPATHIC RECURRENT SPONTANEOUS MISCARRIAGE

OBJECTIVE To investigate the expression pattern of proinflammatory, anti-inflammatory, and angiogenic cytokines and their effect on various mediators of endometrial receptivity in women with idiopathic recurrent spontaneous miscarriage (IRSM). DESIGN A prospective study. SETTING Tertiary care hospital and reproductive health research unit. PATIENT(S) Thirty-six women with IRSM (<35 years) and 30 fertile women as controls matched by age and body mass index undergoing sterilization. INTERVENTION(S) Endometrial biopsies in all women corresponding to the window of implantation. MAIN OUTCOME MEASURE(S) Assessment of endometrial expression of proinflammatory, anti-inflammatory, and angiogenic cytokines, mediators of matrix turnover and angiogenesis, markers of receptivity. RESULT(S) A statistical significantly higher level of proinflammatory cytokines, mediators of matrix turnover and angiogenesis, and a reduced expression of anti-inflammatory and angiogenic cytokines were observed in women with IRSM. Additionally, the markers of endometrial receptivity were poorly expressed in women with IRSM. CONCLUSION(S) Aberrant expression of proinflammatory, anti-inflammatory, and angiogenic cytokines during implantation window in women with IRSM is one of the key factors that adversely affect endometrial development, as evidenced by the inadequate expression of various endometrial receptivity markers.

Identification of Key Contributory Factors Responsible for Vascular Dysfunction in Idiopathic Recurrent Spontaneous Miscarriage

Poor endometrial perfusion during implantation window is reported to be one of the possible causes of idiopathic recurrent spontaneous miscarriage (IRSM). We have tested the hypothesis that certain angiogenic and vasoactive factors are associated with vascular dysfunction during implantation window in IRSM and, therefore, could play a contributory role in making the endometrium unreceptive in these women. This is a prospective case-controlled study carried out on 66 women with IRSM and age and BMI matched 50 fertile women serving as controls. Endometrial expression of pro-inflammatory (IL-1β, TNF-α, IFN-γ, TGF-β1), anti-inflammatory (IL-4, -10), angiogenesis-associated cytokines (IL-2, -6, -8), angiogenic and vasoactive factors including prostaglandin E2 (PGE2), vascular endothelial growth factor (VEGF), endothelial nitric oxide synthase (eNOS), nitric oxide (NO) and adrenomedullin (ADM) were measured during implantation window by ELISA. Subendometrial blood flow (SEBF) was assessed by color Doppler ultrasonography. Multivariate analysis was used to identify the significant factor(s) responsible for vascular dysfunction in IRSM women during window of implantation and further correlated with vascular dysfunction. Endometrial expression of pro-inflammatory cytokines and PGE2 were up-regulated and anti-inflammatory and angiogenesis-associated cytokines down-regulated in IRSM women as compared with controls. Further, the angiogenic and vasoactive factors including VEGF, eNOS, NO and ADM were found to be down-regulated and SEBF grossly affected in these women. Multivariate analysis identified IL-10, followed by VEGF and eNOS as the major factors contributing towards vascular dysfunction in IRSM women. Moreover, these factors strongly correlated with blood flow impairment. This study provides an understanding that IL-10, VEGF and eNOS are the principal key components having a contributory role in endometrial vascular dysfunction in women with IRSM. Down-regulation of these factors is also associated with impaired endometrial perfusion which possibly makes the endometrium unreceptive that may eventually cause early pregnancy loss.

Coinfection of Leptomonas seymouri and Leishmania donovani in Indian Leishmaniasis

ABSTRACT Leishmania donovani is considered the causative organism of visceral leishmaniasis (VL) and post-kala-azar dermal leishmaniasis (PKDL). Testing of 4/29 DNA samples from VL and PKDL patients as well as 2/7 field isolates showed an aberrant internal transcribed spacer 1 (ITS1) restriction fragment length polymorphism (RFLP) pattern, which upon sequencing strongly matched Leptomonas seymouri, thus confirming its presence in Indian leishmaniasis.

Unique Hepatitis B Virus Subgenotype in a Primitive Tribal Community in Eastern India

ABSTRACT Hepatitis B virus (HBV) strains isolated from members of the primitive Paharia ethnic community of Eastern India were studied to gain insight into the genetic diversity and evolution of the virus. The Paharia tribe has remained quite separate from the rest of the Indians and differs culturally, genetically, and linguistically from the mainstream East Indian population, whose HBV strains were previously characterized. Full-length HBV DNA was PCR amplified, cloned, and sequenced. Phylogenetic relationships between the tribal sequences and reference sequences from the mainstream population were assessed, and divergence times of subgenotypes of HBV genotype D were estimated. HBV was found in 2% of the Paharias participating in the study. A predominance of hepatitis B e antigen-negative infection (73%) was observed among the Paharias, and the genome sequences of the HBV strains exhibited relative homogeneity, with a very low prevalence of mutations. The novel feature of Paharia HBV was the exclusive presence of the D5 subgenotype, which was recently identified in Eastern India. Analysis of the four open reading frames (ORFs) of these tribal HBV D5 sequences and comparison with previously reported D1 to D7 sequences enabled the identification of 27 specific amino acid residues, including 6 unique ones, that could be considered D5 signatures. The estimated divergence times among subgenotypes D1 to D5 suggest that D5 was the first to diverge and hence is the most ancient of the D subgenotypes. The presence of a specific, ancient subgenotype of HBV within an ethnically primitive, endogamous population highlights the importance of studies of HBV genetics in well-separated human populations to understand viral transmission between communities and genome evolution.

Copper(II) directs formation of toxic amorphous aggregates resulting in inhibition of hen egg white lysozyme fibrillation under alkaline salt-mediated conditions

Hen egg white lysozyme (HEWL) adopts a molten globule-like state at high pH (~12.75) and is found to form amyloid fibrils at alkaline pH. Here, we report that Cu(II) inhibits self-association of HEWL at pH 12.75 both at 37 and 65 °C. A significant reduction in Thioflavin T fluorescence intensity, attenuation in β-sheet content and reduction in hydrophobic exposure were observed with increasing Cu(II) stoichiometry. Electron paramagnetic resonance spectroscopy suggests a 4N type of coordination pattern around Cu(II) during fibrillation. Cu(II) is also capable of altering the cytotoxicity of the proteinaceous aggregates. Fibrillar species of diverse morphology were found in the absence of Cu(II) with the generation of amorphous aggregates in the presence of Cu(II), which are more toxic compared to the fibrils alone.

1)H NMR serum metabonomics for understanding metabolic dysregulation in women with idiopathic recurrent spontaneous miscarriage during implantation window.

In an attempt to find out the association of metabolic dysregulation with poor endometrial receptivity and pregnancy loss, serum metabonomic profiling of women with idiopathic recurrent spontaneous miscarriage (IRSM) is carried out and compared with fertile controls. (1)H nuclear magnetic resonance (NMR)-based metabonomics was used to obtain serum metabolic profiles of 36 women with IRSM and 28 proven fertile women during the window of implantation. The acquired data were analyzed using multivariate principal component analysis, partial least-squares-discriminant analysis, and orthogonal projection to latent structure with discriminant analysis. A clear metabolic differentiation was evident between IRSM and control samples. The distinguishing metabolites, l-lysine, l-arginine, l-glutamine, l-histidine, l-threonine, l-phenylalanine, and l-tyrosine are significantly up-regulated in IRSM as compared to controls. These altered metabolites may be involved in the molecular mechanism of exaggerated inflammatory response and vascular dysfunction associated with poor endometrial receptivity in women with IRSM. The present work proposes a vital association of metabolic dysfunction with the disease pathogenesis.

Genome wide association study of uric acid in Indian population and interaction of identified variants with type 2 diabetes

Abnormal level of Serum Uric Acid (SUA) is an important marker and risk factor for complex diseases including Type 2 Diabetes. Since genetic determinant of uric acid in Indians is totally unexplored, we tried to identify common variants associated with SUA in Indians using Genome Wide Association Study (GWAS). Association of five known variants in SLC2A9 and SLC22A11 genes with SUA level in 4,834 normoglycemics (1,109 in discovery and 3,725 in validation phase) was revealed with different effect size in Indians compared to other major ethnic population of the world. Combined analysis of 1,077 T2DM subjects (772 in discovery and 305 in validation phase) and normoglycemics revealed additional GWAS signal in ABCG2 gene. Differences in effect sizes of ABCG2 and SLC2A9 gene variants were observed between normoglycemics and T2DM patients. We identified two novel variants near long non-coding RNA genes AL356739.1 and AC064865.1 with nearly genome wide significance level. Meta-analysis and in silico replication in 11,745 individuals from AUSTWIN consortium improved association for rs12206002 in AL356739.1 gene to sub-genome wide association level. Our results extends association of SLC2A9, SLC22A11 and ABCG2 genes with SUA level in Indians and enrich the assemblages of evidence for SUA level and T2DM interrelationship.

A Rare HBV Subgenotype D4 with Unique Genomic Signatures Identified in North-Eastern India –An Emerging Clinical Challenge?

Background/Aims HBV has been classified into ten genotypes (A–J) and multiple subgenotypes, some of which strongly influence disease outcome and their distribution also correlate with human migration. HBV infection is highly prevalent in India and its diverse population provides an excellent opportunity to study the distinctiveness of HBV, its evolution and disease biology in variegated ethnic groups. The North-East India, having international frontiers on three sides, is one of the most ethnically and linguistically diverse region of the country. Given the paucity of information on molecular epidemiology of HBV in this region, the study aimed to carry out an in-depth genetic characterization of HBV prevailing in North-East state of Tripura. Methods From sera of chronically HBV infected patients biochemical/serological tests, HBV DNA quantification, PCR-amplification, sequencing of PreS/S or full-length HBV genomes were done. HBV genotype/subgenotype determination and sequence variability were assessed by MEGA5-software. The evolutionary divergence times of different HBV subgenotypes were estimated by DNAMLK/PHYLIP program while jpHMM method was used to detect any recombination event in HBV genomes. Results HBV genotypes D (89.5%), C (6.6%) and A (3.9%) were detected among chronic carriers. While all HBV/A and HBV/C isolates belonged to subgenotype-A1 and C1 respectively, five subgenotypes of HBV/D (D1–D5) were identified including the first detection of rare D4. These non-recombinant Indian D4 (IndD4) formed a distinct phylogenetic clade, had 2.7% nucleotide divergence and recent evolutionary radiation than other global D4. Ten unique amino acids and 9 novel nucleotide substitutions were identified as IndD4 signatures. All IndD4 carried T120 and R129 in ORF-S that may cause immune/vaccine/diagnostic escape and N128 in ORF-P, implicated as compensatory Lamivudine resistance mutation. Conclusions IndD4 has potential to undermine vaccination programs or anti-viral therapy and its introduction to North-East India is believed to be linked with the settlement of ancient Tibeto-Burman migrants from East-Asia.

Synergistic impact of mutations in Hepatitis B Virus genome contribute to its occult phenotype in chronic Hepatitis C Virus carriers

We characterized occult HBV (OHBV) from hepatitis B surface antigen (HBsAg)-negative chronic HCV carriers of Eastern India to explore the impact of genomic variability of HBV in causing undetectability of HBsAg and low viremia that define the occult phenomenon. Screening of sera samples revealed the presence of OHBV in 17.8% of HCV-infected patients. Determination of full-length OHBV sequences and comparison with that from HBsAg-positive carriers led to the detection of distinct substitutions/mutations in PreS2, S, P and X ORFs and in X-promoter and Enhancer-II of OHBV. These mutations were introduced in wild-type HBV and their effects were evaluated by transfection in Huh7 cells. In vitro assays demonstrated that S-substitutions resulted in antigenically modified HBsAg that escaped detection by immunoassays whereas those in ORF-P caused significant decline in viral replication. Impairment in Enhancer-II and X-promoter activities were noted due to occult-associated mutations that generated reduced pregenomic RNA and intracellular HBV-DNA. Additionally, Enhancer-II mutations altered the small to large surface protein ratio and diminished extracellular HBV-DNA and HBsAg secretion. Further, mutations in PreS2, X and enhancer-II increased Grp78-promoter activity, suggesting that OHBV could trigger endoplasmic reticulum stress. Thus viral mutations contribute synergistically towards the genesis of occult phenotype and disease progression.

HBV quasispecies composition in Lamivudine-failed chronic hepatitis B patients and its influence on virological response to Tenofovir-based rescue therapy

The present study sought to evaluate the structure of HBV quasispecies in Lamivudine (LMV)-failed chronic hepatitis B (CHB) patients and its impact in defining the subsequent virological responses to Tenofovir (TDF)-based rescue-therapy. By analyzing HBV clones encompassing reverse transcriptase (RT) and surface (S) region from LMV-failed and treatment-naïve CHB patients, we identified 5 classical and 12 novel substitutions in HBV/RT and 9 substitutions in immune-epitopes of HBV/S that were significantly associated with LMV failure. In silico analysis showed spatial proximity of some of the newly-identified, mutated RT residues to the RT catalytic centre while most S-substitutions caused alteration in epitope hydrophobicity. TDF administration resulted in virological response in 60% of LMV-failed patients at 24-week but non-response in 40% of patients even after 48-weeks. Significantly high frequencies of 6 S-substitutions and one novel RT-substitution, rtH124N with 6.5-fold-reduced susceptibility to TDF in vitro, were noted at baseline in TDF non-responders than responders. Follow-up studies depicted greater evolutionary drift of HBV quasispecies and significant decline in frequencies of 3 RT and 6 S-substitutions in responder-subgroup after 24-week TDF-therapy while most variants persisted in non-responders. Thus, we identified the HBV-RT/S variants that could potentially predict unfavorable response to LMV/TDF-therapy and impede immune-mediated viral clearance.