Implications of CD45RA and CD45RO T cell subsets in patients of chronic rhinosinusitis with nasal polyposis infected with Aspergillus flavus.

T cell subsets (CD4 and CD8) play a prominent role in the development of chronic rhinosinusitis with nasal polyposis (CRSwNP). Colonization with Aspergillus flavus is recognized as a trigger for the growth of nasal polyps. The fungal proteins initiate the recruitment of T cells into the nasal mucosa, which contributes to the progression of nasal polyps. The study included 50 cases of CRSwNP and 50 healthy controls. Biopsies were subjected to KOH and culture for mycological investigation. We examined the changes in T helper (CD4+) and T cytotoxic (CD8+) in total T cells (CD3+) and expression of naive (CD45RA) and memory (CD45RO) cell markers in T cell subsets in peripheral blood mononuclear cells (PBMCs) challenged by A. flavus antigens in cases before and after treatment and in healthy controls by flow cytometry. Predominantly, A. flavus (86%) identified in nasal polyp biopsies of patients. An increased percentage of CD3+CD4+ T cells observed after A. flavus stimulation in patients when compared with healthy controls. The expression of CD4+CD45RA+ cells was significantly (P < .05) reduced in patients and increased CD4+CD45RO+ was observed upon stimulation with A. flavus in patients when compared with healthy control. Continuous exposure to inhaled fungal spores may induce aberrant immune responses to A. flavus spores, causing an allergic immunological reaction with high CD4+T cell responses, resulting in an unfavourable outcome. Elevated CD4+CD45RO+ T cells may transform the pathogenic response and highlight the chances of A. flavus reactive T cells involvement in prompting inflammation in CRSwNP.

Typical and atypical enteropathogenic Escherichia coli in children with acute diarrhoea: Changing trend in East Delhi.

BACKGROUND: Worldwide around 2 million deaths occur every year due to diarrhoeal illnesses among children less than 5 years of age. Among diarrhoeagenic Escherichia coli, Enteropathogenic E. coli (EPEC) is highly prevalent in both community and hospital settings and is one of the main causes of persistent diarrhea in children in developing countries. EPEC remains underdiagnosed in India due to lack of conventional tools for identification. METHODS: We in this study investigated the prevalence and regional variation of EPEC in paediatric population suffering from diarrhoea in East Delhi, India. Two hundred stool samples were collected from children, aged between 0.5 and 5 years, with acute diarrhoea. E. coli were identified by conventional tests and PCR. RESULTS: We observed 7% atypical EPEC (aEPEC) and 2.5% typical EPEC (tEPEC), with an overall 9.5% EPEC prevalence amongst total samples. E. coli phylogenetic group A was the predominant. The most common age group affected was 6-23 months with common symptoms being vomiting, watery diarrhoea and severe dehydration. High drug resistance pattern was observed in EPEC isolates. CONCLUSION: The study depicts a changing trend of aEPEC over tEPEC in children less than 5 years with diarrhoea, an emerging drug resistant enteropathogen and a public health concern demanding monitoring and surveillance.

TLR-2 expression and dysregulated human Treg/Th17 phenotype in Aspergillus flavus infected patients of chronic rhinosinusitis with nasal polyposis.

BACKGROUND: T helper (Th)17 and regulatory T (Treg) cells with toll-like receptor (TLR)-2 have been acknowledged to play a critical role in chronic rhinosinusitis with nasal polyposis (CRSwNP). However, its pathogenesis has been perplexed by conflicting reports on the role of Th17/Treg cells in patients of distinct ethnicities. We attempted to understand the role of Th responses induced during host defense against Aspergillus flavus. RESULTS: The percentages of Th17 (CD4+CD161+IL23R+) and Treg (CD4+CD25+FoxP3+) cell populations and various cytokine profiles in peripheral blood mononuclear cells (PBMCs) challenged by A. flavus antigens were characterized from 50 CRSwNP cases, before and after treatment, and in 50 healthy controls. TLR-2 expression was analyzed in tissues of cases and controls for disease co-relation. The major pathogen identified in our study was A. flavus by mycological investigations. A marked immune imbalance was noted with elevated Th17 and decreased Tregs in PBMCs of CRSwNP patients after A. flavus stimulation. Comparatively, interleukin (IL)-17 and IL-10 levels were increased, with low transforming growth factor (TGF)-ß levels in A. flavus stimulated PBMC supernatants of patients. The mRNA expression of TLR-2 in polyps of CRSwNP patients indicated significant (p = 0.001) upregulation in comparison to the controls. CONCLUSIONS: Our data highlights the excessive expression of TLR-2 in nasal polyps contributing to the imbalance in Th17/Tregs population in patients. After therapy, recovery of Tregs cells indicates restoration and tissue homeostasis, though high circulating CD4+CD161+ Th17 cells may continue to be a threat to patients predisposed to future recurrences. The constant exposure and tendency of A. flavus to colonize nasal cavities can lead to a Th17 driven airway inflammation. Dysregulated Th17 with TLR-2 promote resistance to treatment and progression to the chronicity of the disease.

Genetic and Functional Characterization of HIV-1 Vpu from HIV-1-Infected North Indian Population.

Acquired immunodeficiency syndrome is a pandemic disease due to increased variability in causative agent in global distribution; it is attributed to various complications in developing the vaccine, namely, error-prone reverse transcriptase, rapid replication, and high recombination rate. Vpu downmodulates CD4 in infected cells, and it targets the newly synthesized CD4 molecules from the endoplasmic reticulum. The aim of this study was to identify the level of genetic changes in the Vpu gene from HIV-1-infected North Indian individuals and determine the functional relevance with respect to the CD4 downregulation potential of this protein. Genomic DNA was isolated from peripheral blood mononuclear cells, and the Vpu gene was polymerase chain reaction amplified with specific primers followed by cloning, sequencing, and sequence analyses using bioinformatic tools for predicting HIV-1 subtypes, recombination events, conservation of domains, and phosphorylation sites. Among all Vpu variants, three of the variants having serine substitution (serine-52 and serine-56 conversion to isoleucine; S52I and S56I) had lost their functional ß-TrcP binding motif. However, the specific determinants for CD4 (V20, W22, S23) and BST-2 (A11, A15, I17, and A19) binding remained highly conserved. The data obtained with Vpu mutants recommend that the serine residue substitutions in cytoplasmic domain distress the CD4 downregulation activity of Vpu. These events are likely to have implications for viral pathogenesis and vaccine formulations.

In-Vitro Subtype-Specific Modulation of HIV-1 Trans-Activator of Transcription (Tat) on RNAi Silencing Suppressor Activity and Cell Death.

Human immunodeficiency virus (HIV) is a global health concern affecting millions of individuals with a wide variety of currently circulating subtypes affecting various regions of the globe. HIV relies on multiple regulatory proteins to modify the host cell to promote replication in infected T cells, and these regulatory proteins can have subtle phenotypic differences between subtypes. One of these proteins, HIV-1 Trans-Activator of Transcription (Tat), is capable of RNA interference (RNAi) Silencing Suppressor (RSS) activity and induction of cell death in T cells. However, the subtype-specific RSS activity and induction of cell death have not been explored. We investigated the ability of Tat subtypes and variants to induce RSS activity and cell death. TatB, from HIV-1 subtype B, was found to be a potent RSS activator by 40% whereas TatC, from HIV-1 subtype C, showed 15% RSS activity while subtype TatC variants exhibited varying levels. A high level of cell death (50-53%) was induced by subtype TatB when compared to subtype TatC (25-28%) and varying levels were observed with subtype TatC variants. These differential activities could be due to variations in the functional domains of Tat. These observations further our understanding of subtype-specific augmentation of Tat in HIV-1 replication and pathogenesis.

Genetic Polymorphisms in the Open Reading Frame of the CCR5 gene From HIV-1 Seronegative and Seropositive Individuals From National Capital Regions of India.

C-C chemokine receptor type 5 (CCR5) serves as a co-receptor for Human immunodeficiency virus (HIV), enabling the virus to enter human CD4 T cells and macrophages. In the absence of CCR5, HIV strains that require CCR5 (R5 or M-tropic HIV) fail to successfully initiate infection. Various natural mutations of the CCR5 gene have been reported to interfere with the HIV-CCR5 interaction, which influences the rate of AIDS progression. Genetic characterization of the CCR5 gene in individuals from the National Capital Regions (NCRs) of India revealed several natural point mutations in HIV seropositive/negative individuals. Furthermore, we identified novel frame-shifts mutations in the CCR5 gene in HIV seronegative individuals, as well as the well reported CCR5Δ32 mutation. Additionally, we observed a number of mutations present only in HIV seropositive individuals. This is the first report to describe the genetic variations of CCR5 in individuals from the NCRs of India and demonstrates the utility of investigating understudied populations to identify novel CCR5 polymorphisms.

Suppressor of Cytokine Signaling 3 (SOCS3) Degrades p65 and Regulate HIV-1 Replication.

Human Immunodeficiency Virus-1 (HIV-1) is known to induce the expression of SOCS3 which is a negative feed-back regulator of inflammatory responses. Here, we demonstrate that reactivation of latent HIV-1 leads to degradation of SOCS3 at early time points. Interestingly, SOCS3 degradation following transfection of HIV-1 RNA as well as polyIC in THP-1 cells further confirmed the role of viral RNA signaling in SOCS3 biology. Degradation of SOCS3 contributes toward viral RNA induced inflammatory responses. NF-κB signaling is also induced upon HIV-1 infection which leads to the production of pro-inflammatory cytokines to control the viral spread. Further investigations revealed that SOCS3 inhibits the expression and activity of p65 by interacting with it and inducing its ubiquitin-dependent proteasomal degradation. SH2 domain was critical for SOCS3-p65 interaction and p65 degradation. We also found that expression of SOCS3 promotes HIV-1 replication. Thus, HIV-1 downregulates SOCS3 in early phase of infection to promote inflammatory responses for large production of activated cells which are suitable for viral spread and induces SOCS3 later on to limit inflammatory responses and ensure viral survival.

Cytomegalovirus aggravates the autoimmune phenomenon in systemic autoimmune diseases.

BACKGROUND: Human Cytomegalovirus (CMV), because of its ability to extensively manipulate host immunity during active infection, has been suggested to be involved in autoimmunity. However, its influence on T-cells and cytokines in systemic autoimmune diseases like systemic lupus erythematosus (SLE) and systemic sclerosis (SSc) is indistinct. METHODS: We investigated the in-vitro response of T lymphocytes from SLE and SSc patients to CMV antigen. Functional activity of T lymphocytes was determined by estimating Th1 (IL-2 and IFN-γ) and Th2 (IL-4 and IL-10) cytokines. RESULTS: We observed that CMV antigen stimulation in-vitro resulted in significant increase in CD4:CD8 T-cell ratio in peripheral blood mononuclear cells (PBMCs) from SLE and SSc patients; response dominated by CD4+ than CD8+ memory T-cells. SSc T-cell response was differentiated by aberrant increase in CD4+CD25+ T-cells. CMV antigen caused elevation in IL-4 and IFN-γ production in both patient PBMCs, whereas IL-2 was also raised in SLE PBMCs. The development of large pool of memory T-cells and overproduction of IFN-γ may result in flare-up of autoimmunity in these patients. CONCLUSION: Our study provides an insight into the immunopathological potential of CMV-reactive immune cells to develop new potential strategies for targeted therapeutic intervention.

Phenotypic and functional profile of Th17 and Treg cells in allergic fungal sinusitis.

Interleukin-17 producing T helper (Th17) and regulatory T cells (Treg) cells have been identified to play a critical role in atopic inflammation. However, conflicting reports on the role of Th17/Treg cells in allergic fungal rhinosinusitis (AFRS) patients of different ethnicities has mystified its pathogenesis. To better understand the pathophysiological mechanisms involved in AFRS, we conducted a prospective, analytical, case-control study involving 40 confirmed immunocompetent AFRS patients and 20 healthy controls. The distribution of Th17 and Treg cells in PBMC, intracellular mRNA expression of retinoid orphan nuclear receptor (RORγt) in Th17 and forkhead transcription factor (FoxP3) in Treg cells, and serum cytokine levels were investigated. Aspergillus flavus was identified from majority (85%) of patient tissue biopsies. Total serum IgE level along with cytokines IL-17, IL-21, IL-1ß and TGF-ß were comparatively elevated in AFRS. Nevertheless, IL-2 and IL-10 were reduced. Higher percentages of CD3+CD4+ T cells in AFRS with increased expression of CD161 and/or IL-23R markers were observed. Though, lower percentages of CD4+CD25+ Treg cells with elevated expression of GITR were patent. Transcription factor RORγt mRNA was upregulated, whereas FoxP3 mRNA was downregulated in AFRS patients. This inclination of Th17/Treg balance towards Th17, and the proposed role of Tregs on Th1 and Th2 cells in AFRS, directed us to conclude that Aspergillus infestation may lead to development of atopy and immunological dysbalance inciting a Th17 driven response, thereby, promoting aggravation of nasal polyposis. The observation may provide new insight into the molecular mechanisms leading to revision of the classical paradigm.

Serum Cytokine Profile in Patients with Chronic Rhinosinusitis with Nasal Polyposis Infected by Aspergillus flavus.

BACKGROUND: Fungi, especially Aspergillus flavus, can cause chronic rhinosinusitis with nasal polyposis and modulate host innate immune components. The objective of this study was to examine the serum levels of T helper (Th) cell subset Th1, Th2, and Th17 cytokines and total IgE in patients having chronic rhinosinusitis with nasal polyposis and Aspergillus flavus infection. METHODS: A case-control study including 40 patients with chronic rhinosinusitis with nasal polyposis and 20 healthy controls was conducted. Aspergillus flavus infection was confirmed by standard potassium hydroxide (KOH) testing, culture, and PCR. Serum samples of all patients and controls were analyzed for various cytokines (interleukins [IL]-1ß, IL-2, IL-4, IL-6, IL-17, IL-21, IL-27, TGF-ß) and total IgE by ELISA. Data from patients with Aspergillus flavus infection and healthy volunteers were compared using the independent t-test and non-parametric Mann-Whitney U test. RESULTS: Aspergillus flavus infection was found in 31 (77.5%) patients with chronic rhinosinusitis with nasal polyposis. IL-1ß, IL-17, IL-21, and TGF-ß serum levels were significantly higher in these patients than in controls; however, IL-2, IL-4, IL-6, and IL-27 levels were lower. Compared with nine (22.5%) patients without Aspergillus flavus infection, IL-17 level was higher while IL-2 level was lower in patients with Aspergillus flavus infection. Total IgE was significantly higher in patients with Aspergillus flavus infection than in controls. CONCLUSIONS: High levels of IL-17 and its regulatory cytokines in patients with chronic rhinosinusitis with nasal polyposis infected by Aspergillus flavus raise a concern about effective disease management and therapeutic recovery. Surgical removal of the nasal polyp being the chief management option, the choice of post-operative drugs may differ in eosinophilic vs. non-eosinophilic nasal polyposis. The prognosis is likely poor, warranting extended care.

FcɛR1α gene polymorphism shows association with high IgE and anti-FcɛR1α in Chronic Rhinosinusitis with Nasal Polyposis.

Despite large number of investigations, the etiology of chronic rhinosinusitis (CRS) remains unclear. Several factors are likely involved in its onset. The genetic susceptibility of IgE-responsiveness likely caused by polymorphism(s) in high affinity receptor for IgE (FcɛR1α) gene can help in understanding the pathophysiology of CRS with nasal polyposis (CRSwNP). A population-based case-control association analysis was conducted to assess the risk of CRSwNP conferred by single nucleotide polymorphisms (SNPs) in FcɛR1α gene in a North Indian cohort. Two promoter and three exonic regions of FcɛR1α gene were amplified and sequenced to investigate five SNPs: rs2427827, rs2251746, rs2298804, rs2298805, and rs2269718. BLAST analysis and subsequent multiple alignments, with known sequences available in the NCBI database, were performed. Total serum IgE and FcɛR1α antibody levels were estimated. Patient IgE level of 461.22 ± 436.43 in comparison to 83.62 ± 58.043 IU/mL in controls (P < 0.0001), and FcɛR1α antibody level of 292.38 ± 115.27 in comparison to 160.56 ± 105.9 in controls (P < 0.0001), depicts their highly significant associations with CRSwNP disease. However, no SNP showed evidence of association with CRSwNP; although relatively higher Odds ratios were observed with rs2427827, rs2251746, and rs2298804. Patient stratification revealed a significant association (P < 0.05) of rs2427827 SNP with high IgE level CRSwNP patients. Nonetheless, we found no SNP associated with low serum IgE level patients. SNP (rs2427827) in the FcɛR1α gene region and high IgE levels may confer susceptibility to CRSwNP in north Indian population. However, further studies including larger sample size, gene-gene, and gene-environment interactions are required for its elucidation.

Correlation of altered expression of a long non-coding RNA, NEAT1, in peripheral blood mononuclear cells with dengue disease progression.

The association of long non-coding RNAs (lncRNAs) with dengue disease progression is currently unknown. Therefore, the present study aimed to identify lncRNAs in different categories of dengue patients and evaluate their association with dengue disease progression. Herein, we examined the expression profiles of lncRNAs and protein-coding genes between other febrile illness (OFI) and different grade of dengue patients through high-throughput RNA sequencing. We identified Nuclear Enriched Abundant Transcript 1 (NEAT1) as one of the differentially expressed lncRNAs (adjusted P ≤ 0.05 and log-fold change ≥ 2) and subsequently validated the expression by qRT-PCR. The co-expression analysis further revealed that NEAT1 and the coding gene IFI27 were highly co-expressed and negatively correlated with dengue severity. Using regression analysis, we observed that NEAT1 expression was significantly dependent on disease progression (Coefficient = -0.27750, SE Coefficient = 0.07145, and t = -3.88).Further, receiver operating characteristic (ROC) curve revealed that NEAT1 expression could discriminate DI from DS (sensitivity and specificity of 100% (95%CI: 85.69 - 97.22) and area under the curve (AUC) = 0.97). Overall, the results of this study offer the first experimental evidence demonstrating the correlation between lncRNAs and severe dengue phenotype. Monitoring NEAT1and IFI27 expression in PBMC may be useful in understanding dengue virus-induced disease progression.

In silico Analyses of Subtype Specific HIV-1 Tat-TAR RNA Interaction Reveals the Structural Determinants for Viral Activity.

HIV-1 Tat transactivates viral genes through strong interaction with TAR RNA. The stem-loop bulged region of TAR consisting of three nucleotides at the position 23-25 and the loop region consisting of six nucleotides at the position 30-35 are essential for viral transactivation. The arginine motif of Tat (five arginine residues on subtype TatC) is critically important for TAR interaction. Any mutations in this motif could lead to reduce transactivation ability and pathogenesis. Here, we identified structurally important residues (arginine and lysine residues) of Tat in this motif could bind to TAR via hydrogen bond interactions which is critical for transactivation. Natural mutant Ser46Phe in the core motif could likely led to conformational change resulting in more hydrogen bond interactions than the wild type Tat making it highly potent transactivator. Importantly, we report the possible probabilities of number of hydrogen bond interactions in the wild type Tat and the mutants with TAR complexes. This study revealed the differential transactivation of subtype B and C Tat could likely be due to the varying number of hydrogen bonds with TAR. Our data support that the N-terminal and the C-terminal domains of Tat is involved in the TAR interactions through hydrogen bonds which is important for transactivation. This study highlights the evolving pattern of structurally important determinants of Tat in the arginine motif for viral transactivation.

RNA-Seq analysis of peripheral blood mononuclear cells reveals unique transcriptional signatures associated with disease progression in dengue patients.

Patients infected with Dengue virus usually present a mild, self-limiting febrile dengue infection (DI) that occasionally leads to a potentially lethal complication, called the severe dengue (DS). The ability to identify the prognostic markers of DS could allow an improved disease intervention and management. To identify the transcriptional signatures associated with the dengue disease progression, we carried out the high-throughput sequencing of the RNA isolated from the peripheral blood mononuclear cells (PBMCs) of the dengue patients of varying severity and compared with that in the patients with other febrile illnesses (OFIs) or the healthy controls. The transcriptional signatures that discriminated the DS patients from OFI and DI patients were broadly related to the pathways involving glycine, serine, and threonine metabolisms, extracellular matrix organization, ubiquitination, and cytokines and inflammatory response. Several upregulated genes in the inflammatory process (MPO, DEFA4, ELANE, AUZ1, CTSG, OLFM4, SLC16A14, and CRISP3) that were associated with the dengue disease progression are known to facilitate leukocyte-mediated migration, and neutrophil activation and degranulation process. High activity of MPO and ELANE in the plasma samples of the follow-up and recovered dengue patients, as well as and the presence of a larger amount of cell-free dsDNA in the DS patients, suggested an association of neutrophil-mediated immunity with dengue disease progression. Careful monitoring of some of these gene transcripts, and control of the activity of proteins encoded by them, may have a great translational significance for the prognosis and management of the dengue patients.

Impact of Genetic Variations in HIV-1 Tat on LTR-Mediated Transcription via TAR RNA Interaction.

HIV-1 evades host defense through mutations and recombination events, generating numerous variants in an infected patient. These variants with an undiminished virulence can multiply rapidly in order to progress to AIDS. One of the targets to intervene in HIV-1 replication is the trans-activator of transcription (Tat), a major regulatory protein that transactivates the long terminal repeat promoter through its interaction with trans-activation response (TAR) RNA. In this study, HIV-1 infected patients (n = 120) from North India revealed Ser46Phe (20%) and Ser61Arg (2%) mutations in the Tat variants with a strong interaction toward TAR leading to enhanced transactivation activities. Molecular dynamics simulation data verified that the variants with this mutation had a higher binding affinity for TAR than both the wild-type Tat and other variants that lacked Ser46Phe and Ser61Arg. Other mutations in Tat conferred varying affinities for TAR interaction leading to differential transactivation abilities. This is the first report from North India with a clinical validation of CD4 counts to demonstrate the influence of Tat genetic variations affecting the stability of Tat and its interaction with TAR. This study highlights the co-evolution pattern of Tat and predominant nucleotides for Tat activity, facilitating the identification of genetic determinants for the attenuation of viral gene expression.

Interleukin-6-174G > C (rs1800795) polymorphism distribution and its association with rheumatoid arthritis: A case-control study and meta-analysis.

The association of interleukin-6 (IL-6)-174G > C (rs1800795) single nucleotide polymorphism (SNP) with the risk of acquiring rheumatoid arthritis (RA) is a relevant issue because of conflicting and consensus lacking reports published in literature. We investigated IL-6-174G > C promoter polymorphism in 34 RA patients, attending a tertiary care hospital in north India. We also performed a meta-analysis, of the previously published studies reporting this genetic relationship, in overall population, and independently in Asian and Caucasian ethnicities to further elucidate this association. A total of 13 studies, including the current one, involving 3291 RA cases and 3812 controls were analyzed. Out of the 13 studies, 6 were from Asian, 6 from Caucasian and 1 from a mixed population. Our case-control study showed significant association of IL-6-174G > C SNP with increased RA risk: allelic (OR = 3.750, 95% CI = 1.800-7.813, p < 0.001); dominant (OR = 2.800, 95% CI = 1.167-6.721, p = 0.021); and recessive (OR = 36.72, 95% CI = 2.004-672.7, p = 0.015). The meta-analysis revealed the increased RA risk associated with IL-6-174G > C SNP in overall population: allelic (OR = 1.650, 95% CI = 1.169-2.329, p = 0.004); homozygous (OR = 1.380, 95% CI = 0.906-2.101, p = 0.133); heterozygous (OR = 1.559, 95% CI = 1.001-2.428, p = 0.049); dominant (OR = 1.663, 95% CI = 1.078-2.567, p = 0.022); and recessive (OR = 1.366, 95% CI = 0.964-1.935, p = 0.079). Subgroup analysis also showed this polymorphism to be associated with increased RA risk in Asian population: allelic (OR = 3.724, 95% CI = 1.361-10.190, p = 0.010); dominant (OR = 3.823, 95% CI = 1.320-11.074, p = 0.013); and recessive (OR = 4.357, 95% CI = 1.634-11.623, p = 0.003), but not in Caucasian population. This meta-analysis shows that IL-6-174G > C SNP is significantly associated with increased RA risk in overall, and specifically in Asian population.

Empirical model for estimating dengue incidence using temperature, rainfall, and relative humidity: a 19-year retrospective analysis in East Delhi.

OBJECTIVES: Aedes mosquitoes are responsible for transmitting the dengue virus. The mosquito lifecycle is known to be influenced by temperature, rainfall, and relative humidity. This retrospective study was planned to investigate whether climatic factors could be used to predict the occurrence of dengue in East Delhi. METHODS: The number of monthly dengue cases reported over 19 years was obtained from the laboratory records of our institution. Monthly data of rainfall, temperature, and humidity collected from a local weather station were correlated with the number of monthly reported dengue cases. One-way analysis of variance was used to analyse whether the climatic parameters differed significantly among seasons. Four models were developed using negative binomial generalized linear model analysis. Monthly rainfall, temperature, humidity, were used as independent variables, and the number of dengue cases reported monthly was used as the dependent variable. The first model considered data from the same month, while the other three models involved incorporating data with a lag phase of 1, 2, and 3 months, respectively. RESULTS: The greatest number of cases was reported during the post-monsoon period each year. Temperature, rainfall, and humidity varied significantly across the pre-monsoon, monsoon, and post-monsoon periods. The best correlation between these three climatic factors and dengue occurrence was at a time lag of 2 months. CONCLUSIONS: This study found that temperature, rainfall, and relative humidity significantly affected dengue occurrence in East Delhi. This weather-based dengue empirical model can forecast potential outbreaks 2-month in advance, providing an early warning system for intensifying dengue control measures.

Tumor necrosis factor (TNF)-α -308G/A (rs1800629) polymorphism distribution in North India and its association with pemphigus: Case-control study and meta-analysis.

Pemphigus is an autoimmune blistering disorder of skin and/or mucosal surfaces characterized by intraepithelial lesions and immunoglobulin-G autoantibodies against desmogleins (proteins critical in cell-to-cell adhesion). Genetic, immunological, hormonal, and environmental factors are known to contribute to its etiology. Tumor necrosis factor-alpha (TNF-α) which plays a key role in pathogenesis of many infectious and inflammatory diseases has been found in high levels in lesional skin and sera of pemphigus patients. However, studies on association of single nucleotide polymorphism (SNP) in promoter region of TNF-α at position -308 affecting G to A transition with pemphigus has been scarce. This study was conducted to evaluate the TNF-α -308G/A SNP distribution in North Indian cohort, and to define the association between the TNF-α -308G/A SNP distribution and pemphigus, globally, by means of meta-analysis. TNF-α -308G/A SNP in pemphigus patients was investigated by cytokine genotyping using genomic DNA by PCR with sequence-specific primers. Meta-analysis of the data, including four previously published studies from other populations, was performed to generate a meaningful relationship. The results of our case-control study indicate non-significant differences between patients and controls in TNF-α -308G/A SNP. The meta-analysis also revealed that TNF-α -308G/A SNP is not associated with pemphigus risk in population at large; however, it may be contributing towards autoimmune phenomenon in pemphigus by being a part of its multi-factorial etiology. This study provides evidence that the TNF-α -308G/A polymorphism is not associated with overall pemphigus susceptibility. Nevertheless, further studies on specific ethnicity and pemphigus variants are necessary to validate the findings.

Superantigen influence in conjunction with cytokine polymorphism potentiates autoimmunity in systemic lupus erythematosus patients.

Risk posed by microbial superantigens in triggering or exacerbating SLE in genetically predisposed individuals, thereby altering the response to its treatment strategies, has not been studied. Using streptococcal pyrogenic exotoxin A and staphylococcal enterotoxin B as prototype superantigens, we have demonstrated that they profoundly affect the magnitude of polyclonal T cell response, particularly CD4(+) T cells and expression of CD45RA and CD45RO, and cytokine secretion in vitro in SLE patient PBMCs. Also, reduced proportions of FoxP3 expressing CD4(+)CD25(+) T cells were detected in SLE as compared to healthy control PBMCs. Furthermore, polymorphism in IL-10 and TGF-ß showed significant association with SLE in our study population. These results indicate that accumulation of superantigen-reactive T cells and cytokine polymorphism may cause disease exacerbation, relapse, or therapeutic resistance in SLE patients. Attempts to contain colonizing and/or superantigen-producing microbial agents in SLE patients in addition to careful monitoring of their therapy may be worthwhile in decreasing disease severity or preventing frequent relapses. The study suggests that superantigen interference in conjunction with cytokine polymorphism may play a role in immune dysregulation, thereby contributing to autoimmunity in SLE. Therefore, changes in T cell phenotypes and cytokine secretion might be good indicators of therapeutic efficacy in these patients.

Genetic and functional characterization of HIV-1 Vif on APOBEC3G degradation: First report of emergence of B/C recombinants from North India.

UNLABELLED: HIV-1 is characterized by high genetic heterogeneity which is a challenge for developing therapeutics. Therefore, it is necessary to understand the extent of genetic variations that HIV is undergoing in North India. The objective of this study was to determine the role of genetic and functional role of Vif on APOBEC3G degradation. Vif is an accessory protein involved in counteracting APOBEC3/F proteins. Genetic analysis of Vif variants revealed that Vif C variants were closely related to South African Vif C whereas Vif B variants and Vif B/C showed distinct geographic locations. This is the first report to show the emergence of Vif B/C in our population. The functional domains, motifs and phosphorylation sites were well conserved. Vif C variants differed in APOBEC3G degradation from Vif B variants. Vif B/C revealed similar levels of APOBEC3G degradation to Vif C confirming the presence of genetic determinants in C-terminal region. High genetic diversity was observed in Vif variants which may cause the emergence of more complex and divergent strains. These results reveal the genetic determinants of Vif in mediating APOBEC3G degradation and highlight the genetic information for the development of anti-viral drugs against HIV. IMPORTANCE: Vif is an accessory HIV-1 protein which plays significant role in the degradation of human DNA-editing factor APOBEC3G, thereby impeding the antiretroviral activity of APOBEC3G. It is known that certain natural polymorphisms in Vif could degrade APOBEC3G relatively higher rate, suggesting its role in HIV-1 pathogenesis. This is the first report from North India showcasing genetic variations and novel polymorphisms in Vif gene. Subtype C is prevalent in India, but for the first time we observed putative B/C recombinants with a little high ability to degrade APOBEC3G indicating adaptation and evolving nature of virus in our population. Indian Vif C variants were able to degrade APOBEC3G well in comparison to Vif B variants. These genetic changes were most likely selected during adaptation of HIV to our population. These results elucidate that the genetic determinants of Vif and highlights the potential targets for therapeutics.