Potent neutralization by a receptor binding domain monoclonal antibody with broad specificity for SARS-CoV-2 JN.1 and other variants

SARS-CoV-2 continues to be a public health burden, driven in-part by its continued antigenic diversification and resulting emergence of new variants. While increasing herd immunity, current vaccines, and therapeutics have improved outcomes for some; prophylactic and treatment interventions that are not compromised by viral evolution of the Spike protein are still needed. Using a rationally designed SARS-CoV-2 Receptor Binding Domain (RBD) - ACE2 fusion protein and differential selection process with native Omicron RBD protein, we developed a recombinant human monoclonal antibody (hmAb) from a convalescent individual following SARS-CoV-2 Omicron infection. The resulting hmAb, 1301B7 potently neutralized a wide range of SARS-CoV-2 variants including the original Wuhan and more recent Omicron JN.1 strain, as well as SARS-CoV. Structure determination of the SARS-CoV-2 EG5.1 Spike/1301B7 Fab complex by cryo-electron microscopy at 3.1Å resolution demonstrates 1301B7 contacts the ACE2 binding site of RBD exclusively through its VH1-69 heavy chain, making contacts using CDRs1-3, as well as framework region 3 (FR3). Broad specificity is achieved through 1301B7 binding to many conserved residues of Omicron variants including Y501 and H505. Consistent with its extensive binding epitope, 1301B7 is able to potently diminish viral burden in the upper and lower respiratory tract and protect mice from challenge with Omicron XBB1.5 and Omicron JN.1 viruses. These results suggest 1301B7 has broad potential to prevent or treat clinical SARS-CoV-2 infections and to guide development of RBD-based universal SARS-CoV-2 prophylactic vaccines and therapeutic approaches.

Highly Cross-Reactive and Protective Influenza A Virus H3N2 Hemagglutinin- and Neuraminidase-Specific Human Monoclonal Antibodies

Due to antigenic drift and shift of influenza A viruses (IAV) and the tendency to elicit predominantly strain-specific antibodies, humanity remains susceptible to new strains of seasonal IAV and is at risk from viruses with pandemic potential for which limited or no immunity may exist. The genetic drift of H3N2 IAV is specifically pronounced, resulting in two distinct clades since 2014. Here, we demonstrate that immunization with a seasonal inactivated influenza vaccine (IIV) results in increased levels of H3N2 IAV-specific serum antibodies against hemagglutinin (HA) and neuraminidase (NA). Detailed analysis of the H3N2 B cell response indicated expansion of H3N2-specific peripheral blood plasmablasts 7 days after IIV immunization which expressed monoclonal antibodies (MAbs) with broad and potent antiviral activity against many H3N2 IAV strains as well as prophylactic and therapeutic activity in mice. These H3N2-specific B cell clonal lineages persisted in CD138+ long-lived bone marrow plasma cells. These results demonstrate that IIV-induced H3N2 human MAbs can protect and treat influenza virus infection in vivo and suggest that IIV can induce a subset of IAV H3N2-specific B cells with broad protective potential, a feature that warrants further study for universal influenza vaccine development. IMPORTANCE Influenza A virus (IAV) infections continue to cause substantial morbidity and mortality despite the availability of seasonal vaccines. The extensive genetic variability in seasonal and potentially pandemic influenza strains necessitates new vaccine strategies that can induce universal protection by focusing the immune response on generating protective antibodies against conserved targets within the influenza virus hemagglutinin and neuraminidase proteins. We have demonstrated that seasonal immunization with inactivated influenza vaccine (IIV) stimulates H3N2-specific monoclonal antibodies in humans that are broad and potent in their neutralization of virus in vitro. These antibodies also provide protection from H3N2 IAV in a mouse model of infection. Furthermore, they persist in the bone marrow, where they are expressed by long-lived antibody-producing plasma cells. This significantly demonstrates that seasonal IIV can induce a subset of H3N2-specific B cells with broad protective potential, a process that if further studied and enhanced could aid in the development of a universal influenza vaccine.

Fc-Effector-Independent in vivo Activity of a Potent Influenza B Neuraminidase Broadly Neutralizing Antibody

Influenza B virus (IBV) contributes to substantial influenza-mediated morbidity and mortality, particularly among children. Similar to influenza A viruses (IAV), the hemagglutinin (HA) and neuraminidase (NA) of IBV undergo antigenic drift, necessitating regular reformulation of seasonal influenza vaccines. NA inhibitors, such as oseltamivir, have reduced activity and clinical efficacy against IBV, while M2 channel inhibitors are only effective against IAV, highlighting the need for improved vaccine and therapeutics for the treatment of seasonal IBV infections. We have previously described a potent human monoclonal antibody (hMAb), 1092D4, that is specific for IBV NA and neutralizes a broad range of IBVs. The anti-viral activity of MAbs can include direct mechanisms such as through neutralization and/or Fc-mediated effector functions that are dependent on accessory cells expressing Fc receptors and that could be impacted by potential host-dependent variability. To discern if the in vivo efficacy of 1092D4 was dependent on Fc-effector function, 1092D4 hMAb with reduced ability to bind to Fc receptors (1092D4-LALAPG) was generated and tested. 1092D4-LALAPG had comparable in vitro binding, neutralization, and inhibition of NA activity to 1092D4. 1092D4-LALAPG was effective at protecting against a lethal challenge of IBV in mice. These results suggest that hMAb 1092D4 in vivo activity is minimally dependent on Fc-effector functions, a characteristic that may extend to other hMAbs that have potent NA inhibition activity.

Mixed Origins: HIV gp120-Specific Memory Develops from Pre-Existing Memory and Naive B Cells Following Vaccination in Humans

The most potent and broad HIV envelope (Env)-specific antibodies often when reverted to their inferred germline versions representing the naive B cell receptor, fail to bind Env, suggesting that the initial responding B cell population not only exclusively comprises a naive population, but also a pre-existing cross-reactive antigen-experienced B cell pool that expands following Env exposure. Previously we isolated gp120-reactive monoclonal antibodies (mAbs) from participants in HVTN 105, an HIV vaccine trial. Using deep sequencing, focused on immunoglobulin G (IgG), IgA, and IgM, VH-lineage tracking, we identified four of these mAb lineages in pre-immune peripheral blood. We also looked through the ∼7 month postvaccination bone marrow, and interestingly, several of these lineages that were found in prevaccination blood were still persistent in the postvaccination bone marrow, including the CD138+ long-lived plasma cell compartment. The majority of the pre-immune lineage members included IgM, however, IgG and IgA members were also prevalent and exhibited somatic hypermutation. These results suggest that vaccine-induced gp120-specific antibody lineages originate from both naive and cross-reactive memory B cells. ClinicalTrials.gov NCT02207920.

Potent universal beta-coronavirus therapeutic activity mediated by direct respiratory administration of a Spike S2 domain-specific human neutralizing monoclonal antibody

Severe Acute Respiratory Syndrome Coronavirus-2 (SARS-CoV-2) marks the third novel β-coronavirus to cause significant human mortality in the last two decades. Although vaccines are available, too few have been administered worldwide to keep the virus in check and to prevent mutations leading to immune escape. To determine if antibodies could be identified with universal coronavirus activity, plasma from convalescent subjects was screened for IgG against a stabilized pre-fusion SARS-CoV-2 spike S2 domain, which is highly conserved between human β-coronavirus. From these subjects, several S2-specific human monoclonal antibodies (hmAbs) were developed that neutralized SARS-CoV-2 with recognition of all variants of concern (VoC) tested (Beta, Gamma, Delta, Epsilon, and Omicron). The hmAb 1249A8 emerged as the most potent and broad hmAb, able to recognize all human β-coronavirus and neutralize SARS-CoV and MERS-CoV. 1249A8 demonstrated significant prophylactic activity in K18 hACE2 mice infected with SARS-CoV-2 lineage A and lineage B Beta, and Omicron VoC. 1249A8 delivered as a single 4 mg/kg intranasal (i.n.) dose to hamsters 12 hours following infection with SARS-CoV-2 Delta protected them from weight loss, with therapeutic activity further enhanced when combined with 1213H7, an S1-specific neutralizing hmAb. As little as 2 mg/kg of 1249A8 i.n. dose 12 hours following infection with SARS-CoV Urbani strain, protected hamsters from weight loss and significantly reduced upper and lower respiratory viral burden. These results indicate in vivo cooperativity between S1 and S2 specific neutralizing hmAbs and that potent universal coronavirus neutralizing mAbs with therapeutic potential can be induced in humans and can guide universal coronavirus vaccine development.

HIV gp120-specific memory develops from pre-existing memory and naive B cells following vaccination in humans

The most potent and broad HIV envelope (Env)-specific antibodies often when reverted to their inferred germline versions representing the naïve B cell receptor, fail to bind Env suggesting that the initial responding B cell population is not exclusively comprised of a naïve population, but also a pre-existing cross-reactive antigen-experienced B cell pool that expands following Env exposure. Previously we isolated gp120-reactive monoclonal antibodies (mAbs) from participants from HVTN105, a phase I trial testing AIDSVAX B/E (gp120 protein) combined with a DNA immunogen. Using MiSeq-based deep sequencing VH-lineage tracking we identified several of these mAb lineages in pre-immune peripheral blood. Additionally, we sought to characterize the gp120-specific B cell repertoire prior to immunization, and the features of those pre-immune B cell clonal lineages that ultimately respond to the vaccine. Several of these pre-immune lineages also persisted in the bone marrow, including CD138+ long-lived plasma cell compartment, ~7 months after the final vaccination. Greater gp120 binding activity was observed from the non-naïve pre-immune VH members than their germline VH versions. The majority of the pre-immune gp120-reactive lineages included IgM, however IgG and IgA members were also predominant prior to vaccination. Additionally, the majority of the pre-immune lineage members exhibited somatic hypermutation prior to vaccination, suggesting that the vaccine-induced gp120-specific antibody lineages originated from both naïve B cells and cross-reactive memory B cells.

Supported by grants from the NIH (R01AI117787, R21AI116285).

Pan-coronavirus neutralizing S2 human monoclonal antibodies and utility of direct respiratory administration as combination therapy with S1 antibodies against SARS-CoV-2

To determine if pan-coronavirus neutralizing antibodies are induced by SARS-CoV-2 infection, human monoclonal antibodies (mAb) targeting the highly conserved S2 domain of the Spike glycoprotein were cloned from B cells isolated from convalescent patients with rationally designed SARS-CoV-2 stabilized S2 and SARS-CoV/SARS-CoV-2 S1S2 chimera recombinant protein probes. mAbs emerged capable of binding SARS-CoV-2, including the variants of concern (Beta, Gamma, Delta, and Omicron), SARS-CoV and MERS-CoV. The most potent neutralizing mAb with greatest breadth, 1249A8, recognizes all beta-coronaviruses tested including high affinity for SARS-CoV-2, SARS-CoV, and MERS-CoV. The 1249A8 lineage appears to have developed from a pre-existing OC43-specific memory B cell that was expanded as result of SARS-CoV-2 infection, and further expanded following COVID-19 vaccination. Treating K18 hACE2 transgenic mice with 1249A8 intraperitoneally prior to co-infection with SARS-CoV-2 Wa-1 and Beta VoC strains prevented weight loss and death, with viral titers below detectable levels by 4 days post-infection. 1249A8 delivered as a single 4mg/kg intranasal (i.n.) dose to hamsters 12 hours following infection with SARS-CoV-2/Delta significantly protected them from weight loss, with therapeutic activity enhanced when combined with an S1-specific neutralizing mAb. As little as 2 mg/kg of 1249A8 i.n. 20 hours following infection with SARS-CoV/Urbani protected hamsters from weight loss. 1249A8 recognizes a highly conserved region near HR2 of the S2 domain of Spike. These results indicate that potent pan-coronavirus neutralizing mAbs with therapeutic potential can be induced in humans and can inform pan-coronavirus vaccine development.

Supported in-part by Aridis Pharmaceuticals and NIH (R01AI161175).

Targeting tonsillar B cells with IL-9 and IL-33 enhances the rhesus macaque humoral response to DNA/protein-based HIV envelope vaccine

Development of an effective HIV vaccine is dependent on the quantity and quality of HIV Envelope specific antibody at the mucosal sites. Priming of the oral mucosa is a promising approach to generate mucosal antibody at HIV entry sites. Our recent work in mice has demonstrated the ability of IL-9 and IL-33, known regulators of mucosal immunity, to promote robust development of HIV Env-specific IgG; in addition they increase the breadth, magnitude, and durability of the Env-specific IgG response when combined with the DNA/protein HIV Env immunogen platform VC10014, which elicits Tier 2 neutralizing antibody in rhesus macaques. We hypothesized that conditioning the tonsil microenvironment with IL-9 or IL-33 would enable the rapid induction of durable and effective mucosal humoral immunity by the VC10014 DNA/protein HIV vaccine platform. Rhesus macaques were primed with VC10014 gp160 DNA plasmids in the absence or presence of IL-9 or IL-33 intra-tonsillar (IT), followed by intramuscular (IM) boosting with the DNA/protein HIV vaccine regimen. IT immunization with IL-9 or IL33 induced plasma Env-specific IgG that was present as early as week 6, mucosal Env-specific IgG and heterologous plasma neutralizing antibody. IL-33 treated animals exhibited the greatest number of germinal centers (GCs) and largest GCs following the first IM boost whereas IL-9 treated animals showed the greatest number of GCs following the second IM boost in the draining lymph nodes. The difference in kinetics, with IL-33 promoting an earlier B cell response, and IL-9 promoting greater magnitude later, may suggest that IL-9 and IL-33 promote the development of qualitatively different B cells subsets and may have synergistic potential in HIV vaccine development.

Supported by a grant from NIH (R01DE027245).

Potent universal-coronavirus therapeutic activity mediated by direct respiratory administration of a Spike S2 domain-specific human neutralizing monoclonal antibody

Severe Acute Respiratory Syndrome Coronavirus-2 (SARS-CoV-2) marks the third novel β-coronavirus to cause significant human mortality in the last two decades. Although vaccines are available, too few have been administered worldwide to keep the virus in check and to prevent mutations leading to immune escape. To determine if antibodies could be identified with universal coronavirus activity, plasma from convalescent subjects was screened for IgG against a stabilized pre-fusion SARS-CoV-2 spike S2 domain, which is highly conserved between human β-coronavirus. From these subjects, several S2-specific human monoclonal antibodies (hmAbs) were developed that neutralized SARS-CoV-2 with recognition of all variants of concern (VoC) tested (Beta, Gamma, Delta, Epsilon, and Omicron). The hmAb 1249A8 emerged as the most potent and broad hmAb, able to recognize all human β-coronavirus and neutralize SARS-CoV and MERS-CoV. 1249A8 demonstrated significant prophylactic activity in K18 hACE2 mice infected with SARS-CoV-2 lineage A and lineage B Beta, and Omicron VoC. 1249A8 delivered as a single 4 mg/kg intranasal (i.n.) dose to hamsters 12 hours following infection with SARS-CoV-2 Delta protected them from weight loss, with therapeutic activity further enhanced when combined with 1213H7, an S1-specific neutralizing hmAb. As little as 2 mg/kg of 1249A8 i.n. dose 12 hours following infection with SARS-CoV Urbani strain, protected hamsters from weight loss and significantly reduced upper and lower respiratory viral burden. These results indicate in vivo cooperativity between S1 and S2 specific neutralizing hmAbs and that potent universal coronavirus neutralizing mAbs with therapeutic potential can be induced in humans and can guide universal coronavirus vaccine development.

Modernising physician resource planning: a national interactive web platform for Canadian medical trainees

Background

Healthcare systems rely heavily upon human resources to ensure high-quality access to care for the general population. With significant health worker shortages predicted worldwide in the coming decades, maximizing the current workforce by means of a physician resource planning (PRP) strategy that ensures the right number, mix, and distribution of physicians to meet population needs is warranted. In Canada, there is an insufficient number of primary care providers, and disproportionately low numbers of specialist physicians in rural compared to urban regions. Currently, Canadian medical students are not effectively included in PRP strategy and lack the required information for career orientation to help rebalance the population’s workforce needs. This paper present the Health Human Resource (HHR) Platform, a comprehensive web tool that includes relevant workforce data to empower medical students in choosing a discipline based on both personal interests and social accountability.

Results

Physician workforce data, comments from Canadian residency program directors, and career planning resources were collected by the Canadian Federation of Medical Student’s (CFMS) HHR Task Force. This information was consolidated to create a national interactive platform that uses a map, comparison table, and trend graphs to illustrate over 500,000 unique data points from 37 datasets, including specific information and resources spanning 62 medical specialties from 2015 onwards. There was a 24.6% response rate for program director comments. During the first 4 months of the HHR Platform launch, there were 2434 different users, of which 985 were returning, with an average of 20.0 users per day spending on average 3 min on the platform.

Conclusions

The HHR Platform constitutes a national approach to PRP informing medical students on the mix and distribution of physicians needed to meet the future healthcare demands of the Canadian population.

CD4+ T Cells Are Dispensable for Induction of Broad Heterologous HIV Neutralizing Antibodies in Rhesus Macaques

Induction of broadly neutralizing antibodies (bNAbs) is a major goal for HIV vaccine development. HIV envelope glycoprotein (Env)-specific bNAbs isolated from HIV-infected individuals exhibit substantial somatic hypermutation and correlate with T follicular helper (Tfh) responses. Using the VC10014 DNA-protein co-immunization vaccine platform consisting of gp160 plasmids and gp140 trimeric proteins derived from an HIV-1 infected subject that developed bNAbs, we determined the characteristics of the Env-specific humoral response in vaccinated rhesus macaques in the context of CD4+ T cell depletion. Unexpectedly, both CD4+ depleted and non-depleted animals developed comparable Tier 1 and 2 heterologous HIV-1 neutralizing plasma antibody titers. There was no deficit in protection from SHIV challenge, no diminution of titers of HIV Env-specific cross-clade binding antibodies, antibody dependent cellular phagocytosis, or antibody-dependent complement deposition in the CD4+ depleted animals. These collective results suggest that in the presence of diminished CD4+ T cell help, HIV neutralizing antibodies were still generated, which may have implications for developing effective HIV vaccine strategies.

Unusual Growth and Hydration Characteristics of Oil Solubilized Micelles in Aqueous Pluronic Systems

Lipophile induced modulations of self-assembly characteristics in aqueous Pluronic systems merit attention because of wide-ranging uses of Pluronics as solubilizing agents of lipophilic substances. In this paper, we report unusual evolutions of structural and hydration properties in lavender essential oil (LO) solubilized Pluronic P85 aqueous micellar systems as a function of micellar volume fraction and temperature. Our DLS, SANS, and viscometry studies show that the spherical-to-wormlike micellar structural transition observed in 1% P85 solutions upon solubilization of LO quite unexpectedly gets suppressed with increased P85 concentration to ≥5%. Detailed SANS studies reveal that the core sizes of the oil solubilized micelles cannot attain the threshold value required for the onset of structural transition at higher copolymer concentrations due to their progressive shrinking with an increase in P85 concentration. Oil solubilized P85 solutions show two cloud points and very interestingly exhibit micellar growth upon cooling to their lower cloud points. Steady state fluorescence studies explain this based on increasing dehydration of micellar corona with a decrease in temperature, very much opposite to what is observed in pure aqueous Pluronic systems. The results give new insight into viscous flow properties and low temperature storage possibilities of oil solubilized aqueous Pluronic systems.

Therapeutic activity of an inhaled potent SARS-CoV-2 neutralizing human monoclonal antibody in hamsters

SARS-CoV-2 infection results in viral burden in the respiratory tract, enabling transmission and leading to substantial lung pathology. The 1212C2 fully human monoclonal antibody was derived from an IgM memory B cell of a COVID-19 patient, has high affinity for the Spike protein receptor binding domain, neutralizes SARS-CoV-2, and exhibits in vivo prophylactic and therapeutic activity in hamsters when delivered intraperitoneally, reducing upper and lower respiratory viral burden and lung pathology. Inhalation of nebulized 1212C2 at levels as low as 0.6 mg/kg, corresponding to 0.03 mg/kg lung-deposited dose, reduced the viral burden below the detection limit and mitigated lung pathology. The therapeutic efficacy of an exceedingly low dose of inhaled 1212C2 supports the rationale for local lung delivery for dose-sparing benefits, as compared to the conventional parenteral route of administration. These results suggest that the clinical development of 1212C2 formulated and delivered via inhalation for the treatment of SARS-CoV-2 infection should be considered.

The 1212C2 human monoclonal antibody potently neutralizes SARS-CoV-2

1212C2 mAb was isolated from an IgM memory B cell of a recovered COVID-19 patient

Inhaled 1212C2 mAb is rapidly distributed in the lungs

Inhaled 1212C2 mAb treatment reduces viral burden and lung pathology in hamsters

Persistence of HIV-1 Env-Specific Plasmablast Lineages in Plasma Cells after Vaccination in Humans

Induction of persistent HIV-1 Envelope (Env) specific antibody (Ab) is a primary goal of HIV vaccine strategies; however, it is unclear whether HIV Env immunization in humans induces bone marrow plasma cells, the presumed source of long-lived systemic Ab. To define the features of Env-specific plasma cells after vaccination, samples were obtained from HVTN 105, a phase I trial testing the same gp120 protein immunogen, AIDSVAX B/E, used in RV144, along with a DNA immunogen in various prime and boost strategies. Boosting regimens that included AIDSVAX B/E induced robust peripheral blood plasmablast responses. The Env-specific immunoglobulin repertoire of the plasmablasts is dominated by VH1 gene usage and targeting of the V3 region. Numerous plasmablast-derived immunoglobulin lineages persisted in the bone marrow >8 months after immunization, including in the CD138+ long-lived plasma cell compartment. These findings identify a cellular linkage for the development of sustained Env-specific Abs following vaccination in humans.

CD4+ T cells are dispensable for induction of heterologous tier 2 HIV neutralizing antibodies in rhesus macaques

Induction of a sustained and broad neutralizing antibody (Ab) response is a major goal in developing a protective HIV vaccine. Many HIV Envelope (Env)-specific broadly neutralizing antibodies isolated to date exhibit substantial somatic hypermutation, and their development in HIV infected individuals has been correlated with T follicular helper responses. This has bolstered the rational that a robust CD4+ T helper cell response will likely be required for the induction of such HIV broadly neutralizing antibody responses by vaccination. Using the VC10014 DNA-protein co-immunization vaccine platform consisting of gp160 envelope plasmids and gp140 trimeric envelope proteins derived from a clade B HIV-1 infected subject who developed broadly neutralizing serum Abs, and which has been previously shown to induce Tier 2 heterologous neutralizing Abs in rabbits and rhesus macaques, we determined the influence of CD4+ T cell depletion during the vaccination regimen on the characteristics of the Env-specific humoral response in rhesus macaques. Both CD4+ depleted and non-depleted animals developed Tier 2 heterologous neutralizing plasma antibodies, with no inferiority in titers among the CD4+ T cell depleted animals. Similarly, there was no diminishment of titers of HIV Env-specific cross-clade binding antibodies, antibody dependent cellular phagocytosis or antibody dependent complement deposition in the CD4+ depleted animals. These results suggest that HIV neutralizing antibodies can be induced in the absence of robust CD4+ T cell help, which may have implications for developing effective HIV vaccine strategies.

Mixed origins: HIV vaccine induced Env-specific antibodies arise from naive and cross-reactive memory B cells

The most potent and broad HIV envelope (Env)-specific antibodies (Abs) often when reverted to their inferred germline versions representing the naïve B cell receptor, usually fail to bind Env. This may suggest that the primary B cell population that responds to the initial Env exposure is not exclusively comprised of a naïve population, but also a pre-existing cross-reactive antigen-experienced B cell pool that expands following Env exposure. Previously we isolated 66 gp120 reactive mAbs from participants from HVTN105, a phase I trial testing AIDSVAX B/E (gp120 protein) combined with a DNA immunogen. In order to determine the origin of these mAb producing B cells, we used Miseq-based VH lineage tracking approach and identified several of these mAb lineages in peripheral blood prior to vaccination (pre-immune). Further, several of these pre-immune lineages also persist in the bone marrow ~8 months after the final vaccination, including within in the CD138+ long-lived plasma cell compartment. When tested by ELISA, pre-immune mAbs bound to HIV Env, with relatively lower ability than their post-vaccination forms, but showed higher reactivity than their germline form. The majority of the pre-immune lineage members were IgM, however IgG and IgA members were predominant prior to vaccination and the majority of the pre-immune lineage members exhibited somatic hypermutation. These results may indicate that the vaccine-induced Env-specific antibody lineages originated from a mixed ancestor population of naïve and cross-reactive memory cells.

Altering the X-ray Scattering Contrast of Triton X-100 Micelles and Its Trapping in a Supercooled Solvent

The structure of core-shell micelles formed by nonionic surfactant Triton X-100 (TX-100) in a supercooled glucose-urea melt is investigated by contrast variation small-angle X-ray scattering (SAXS), small angle neutron scattering (SANS), and HR-TEM. Cooling a molten mixture of glucose-urea (weight ratio of 3:2) to room temperature yields a supercooled solvent without crystallization that can be used for trapping micelles of TX-100. By use of a combination of water and glucose-urea mixture at different proportions as solvent for micellization, the scattering length density (SLD) of the solvent can be tuned to match the shell contrast of the micelles. A systematic analysis of SAXS and SANS data with different SLD of solvent permits a quantitative evaluation of electron density profile of micelles in different matrices. The core of TX-100 micelles shows significant swelling in glucose-urea melt, as compared to that in water. The dimension and morphology of micelles were evaluated by scattering techniques and HR-TEM. Dynamic light scattering (DLS) studies suggest that, unlike micelles in water, the diffusion of micelles in supercooled glucose-urea melt decreased by several orders of magnitude.

IL-33 enhances the kinetics and quality of the antibody response to a DNA and protein-based HIV-1 Env vaccine

Induction of a sustained and broad antibody (Ab) response is a major goal in developing a protective HIV-1 vaccine. DNA priming alone shows reduced levels of immunogenicity; however, when combined with protein boosting is an attractive vaccination strategy for induction of humoral responses. Using the VC10014 DNA and protein-based vaccine consisting of HIV-1 envelope (Env) gp160 plasmids and trimeric gp140 proteins derived from an HIV-1 clade B infected subject who developed broadly neutralizing serum Abs, and which has been previously demonstrated to induce Tier 2 heterologous neutralizing Abs in rhesus macaques, we evaluated whether MPLA and IL-33 when administered during the DNA priming phase enhances the humoral response in mice. The addition of IL-33 during the gp160 DNA priming phase resulted in high titer gp120-specific plasma IgG after the first immunization. The IL-33 treated mice had higher plasma IgG Ab avidity, breadth, and durability after DNA and protein co-immunization with alum adjuvant as compared to MPLA and alum only treated mice. IL-33 was also associated with a significant IgM Env-specific response and expansion of peritoneal and splenic B-1b B cells. These results indicate that DNA priming in the presence of exogenous IL-33 qualitatively alters the HIV-1 Env-specific humoral response, improving the kinetics and breadth of potentially protective Ab.

Induction and relationship of HIV Envelope-specific B cells in the peripheral blood and bone marrow following vaccination in humans

Induction of long-lived plasma cells producing protective HIV-1 Envelope (Env)-specific antibody (Ab) is a primary goal of HIV vaccine strategies. However, vaccine-induced Env-specific human plasma cells have not yet been identified. In an effort to do so, samples were obtained from HVTN 105, a phase I trial in which participants were immunized with the same bivalent gp120 protein, AIDSVAX B/E, as used in RV144, although combined with a DNA immunogen (instead of ALVAC-HIV) in various prime/boost strategies. Participants who received a boosting regimen that included AIDSVAX B/E had robust peripheral blood plasmablast responses as measured by Env-specific ELISpot (n=21) and flow cytometry (n=20). The Env-specific immunoglobulin repertoire of the plasmablasts, assessed by monoclonal Ab generation (>110 mAbs total from 15 participants), was dominated by VH1 gene usage (~60%, VH1-2>VH1-46>VH1-24), and had modest mutation from germline (~5%). Ongoing epitope mapping has indicated V3 is a dominant target; however other regions including V1/V2 and C1/C5 were also targeted. The majority of the mAbs are high avidity, and a subset can mediate Ab-dependent cellular phagocytosis; additional functional analysis is ongoing. Bone marrow was evaluated ~7 months after immunization (n=3), and although ELISpot of CD138+ plasma cells could readily detect influenza specific IgG Ab secreting cells (ASCs), Env-specific IgG ASCs were not convincingly detected by ELISpot. However, when using VH deep sequencing of the bone marrow (n=4), multiple members of plasmablast-derived mAb clonal lineages were detected. Our results indicate that HIV-1 Env-specific B cells are present in human bone marrow after vaccination, but may persist at very low frequency.

A Highly Potent and Broadly Neutralizing H1 Influenza-Specific Human Monoclonal Antibody

Influenza’s propensity for antigenic drift and shift, and to elicit predominantly strain specific antibodies (Abs) leaves humanity susceptible to waves of new strains with pandemic potential for which limited or no immunity may exist. Subsequently new clinical interventions are needed. To identify hemagglutinin (HA) epitopes that if targeted may confer universally protective humoral immunity, we examined plasmablasts from a subject that was immunized with the seasonal influenza inactivated vaccine, and isolated a human monoclonal Ab (mAb), KPF1. KPF1 has broad and potent neutralizing activity against H1 influenza viruses, and recognized 83% of all H1 isolates tested, including the pandemic 1918 H1. Prophylactically, KPF1 treatment resulted in 100% survival of mice from lethal challenge with multiple H1 influenza strains and when given as late as 72 h after challenge with A/California/04/2009 H1N1, resulted in 80% survival. KPF1 recognizes a novel epitope in the HA globular head, which includes a highly conserved amino acid, between the Ca and Cb antigenic sites. Although recent HA stalk-specific mAbs have broader reactivity, their potency is substantially limited, suggesting that cocktails of broadly reactive and highly potent HA globular head-specific mAbs, like KPF1, may have greater clinical feasibility for the treatment of influenza infections.

IL-33 enhances the induction, durability, and breadth of the antibody response to a DNA/protein-based HIV Env vaccine

Induction of a sustained and broad antibody (Ab) response is a major goal in developing a protective HIV vaccine. DNA is an attractive priming strategy when combined with protein or viral vector boosting; however, DNA priming alone fails to induce a substantial Ab response, limiting its potential as a stand-alone immunogen. Using the VC10014 DNA/protein vaccine consisting of gp160 plasmids and gp140 proteins derived from an HIV clade B infected subject who developed broadly neutralizing serum Abs, and which has been previously shown to induce Tier 2 heterologous neutralizing Abs in rhesus macaques, we screened a panel of factors in C57BL/6 mice for their ability to enhance the Env-specific Ab response. IL-33, an alarmin, emerged as the lead candidate. The addition of recombinant IL-33 during the gp160 DNA priming phase dramatically changed the kinetics of the Ab response, inducing serum gp120-specific IgG (>1:12,500 titer) after a single DNA immunization, which was not detectable in mice that did not receive IL-33 (p<0.0001). Then following boosting with DNA/protein coimmunization in Alum, gp120-specific IgG levels were extraordinarily durable, remaining stable even at 6 weeks after final immunization compared to mice not receiving IL-33 (p<0.0001), in which they rapidly declined. IL-33 also increased the cross-clade breadth and avidity of the serum gp120-specific IgG response. Analysis of the Env-specific B cell immunoglobulin repertoire and the IL-33 mechanism of action is ongoing. These results demonstrate the profound effect that priming conditions can have on the quality of the Env-specific antibody response.

Molecular cloning of IgZ heavy chain isotype in Catla catla and comparative expression profile of IgZ and IgM following pathogenic infection

Immunoglobulins serve as a crucial arm of the adaptive immune system against detrimental pathogenic threats in teleosts. However, whether the novel Ig isotype IgZ is present in the Indian major carp, Catla catla, has not yet been elucidated. The present study reports the presence of IgZ ortholog in C. catla (CcIgZ) and further demonstrates its comparative tissue specific expression with IgM (CcIgM) in response to bacterial and parasitic stimulation. The putative 139 amino acid sequence of IgZ heavy chain cDNA of C. catla showed homology with IgZ constant domains of other teleosts. Phylogenetic analysis of the predicted IgZ transcript sequence clustered with previously identified IgZ heavy chain sequences of Cyprinidae family members. The inductive expression profiles of IgZ and IgM genes were evaluated in immunologically relevant tissues at 24, 48 and 72 hr post infection with Aeromonas hydrophila, Streptococcus uberis and Argulus sp. Both CcIgZ and CcIgM were expressed most strongly in the kidneys of healthy fish. Basal expression of CcIgM transcript was higher than that of CcIgZ in all the examined tissues. Stimulation with bacteria triggered significant increase of IgZ in the intestine (P < 0.001) and spleen (P < 0.01), whereas IgM was relatively up-regulated in blood (P < 0.001) after stimulation with each of the three pathogens assessed. The study is the first to report identification of IgZ in C. catla. Further, it provides insights into the differential expression profiles of IgZ and IgM isotypes against various pathogenic infection in C. catla, which may facilitate better prophylaxis again such infections.

Molecular cloning and characterization of LrTLR4, analysis of its inductive expression and associated down-stream signaling molecules following lipopolysaccharide stimulation and Gram-negative bacterial infection

Toll-like receptors (TLRs) play key roles in innate immunity from lower to higher vertebrates. Among various TLR types, TLR4 was reported to recognize LPS in higher vertebrates resulting in the activation of down-stream signaling pathway. Except in some teleosts, function of TLR4 in most fish species including rohu (Labeo rohita) a commercially important fish species in the South-East Asian countries remained unknown. To investigate it, full-length cDNA of Labeo rohita TLR4 (LrTLR4) was cloned, and it consisted of 2729 bp, with a single ORF of 2469 bp encoding a polypeptide of 822 aa with a predicted molecular mass of 94.753 kDa. Structurally, LrTLR4 consisted of 25 LRRs (leucine rich repeat regions), one TM (trans-membrane) domain and one TIR (Toll/interleukin-1 receptor) domain, and was similar to higher vertebrate's TLR4. Phylogenetically, LrTLR4 exhibited highest (85%) identity with the common carp TLR4b amino acids sequence, and formed a separate subgroup in the phylogenetic tree. LrTLR4 was widely expressed in all tested organs/tissues, and amidst the tissues highest expression was detected in blood and the lowest in eye. In response to LPS-stimulation, LrTLR4 was induced with the activation of MyD88-dependent and TRIF-dependent signaling pathway resulting in pro-inflammatory cytokines (interleukin 6 and 8) and type I IFN gene expression. Infection of rohu with a Gram-negative fish pathogen (Aeromonas hydrophila), also activated LrTLR4. Together, these findings suggest the important role of TLR4 in LPS sensing and augmentation of innate immunity against Gram-negative bacterial infection in fish.

Insight of solvent extraction process: Reassessment of trace level determinations

Solvent extraction is hoary yet modern technique with great scope of research due to the various intriguing phenomena in the system. Tri-n-butyl phosphate (TBP) is a well known extractant which has been extensively used for separation of uranium matrix prior to elemental profiling. In this paper, one of the impurities namely Fe is being considered as it posed a challenge to the separation due to its co-extraction with TBP along with uranium. In these studies, for the first time, the existence of cation-cation inner sphere complexes between the UO2(2+)and Fe(3+) ions in both aqueous and organic phases have been establisted in addition to the selective separation of iron from uranium sample matrix using only TBP. The data from both spectrophotometric and thermophysical studies corroborated one another confirming the presence of cation-cation interactions (CCIs). The developed solvent extraction with only TBP showed almost no interferences on the iron extraction from matrix uranium and other co-ions like aluminum and copper. This has been the first time application of pure TBP for selective removal of iron from uranium samples. The procedure possessed excellent reproducibility and robustness.

Lactobacillus acidophilus attenuates Aeromonas hydrophila induced cytotoxicity in catla thymus macrophages by modulating oxidative stress and inflammation

The pathogenesis of Aeromonas hydrophila, a potent fish pathogen, is attributed to its ability to cause motile aeromonad septicaemia leading to apoptosis in a myriad of fish species, including freshwater carp Catla catla. However, the underlying mechanism of antagonistic activity of probiotics against A. hydrophila induced apoptosis is not elucidated due to lack of appropriate in-vitro models. This study reported that the exposure of catla thymus macrophages (CTM) to A. hydrophila markedly induced cellular injuries as evidenced by elevated levels of reactive oxygen species (ROS), reactive nitrogen species (RNS), increased apoptosis, DNA damage and decreased cellular viability. Flow cytometry analysis and Annexin-V/propidium iodide assay further confirmed increased ROS positive cells leading to cell death after infection. The quantitative real-time PCR analysis, also revealed upregulation of inducible nitric-oxide synthase (iNOS), pro-inflammatory cytokine (TNFα), cyclooxygenase2 (COX-2) and downregulation of anti-inflammatory cytokine (IL-10). Pretreatment of cells with probiotic, Lactobacillus acidophilus attenuated A. hydrophila induced apoptosis as evident from the decrease in the levels of ROS, RNS and DNA damage. Significant increase (P≤0.05) in expression of TNFα and IL-10 and decrease in iNOS and COX-2 was observed on probiotic stimulation. In-vivo study using catla fingerlings confirmed similar pattern of ROS, iNOS, NO production and cytokine expression in thymus. This study provides a comprehensive insight into the mechanistic basis of L. acidophilus induced macrophage mediated inflammatory response against A. hydrophila in CTM cells. Further, it speculates the possibility of using cost-effective in-vitro models for screening probiotic candidates of therapeutic potential in aquaculture industry.

Modulation of TLR2, TLR4, TLR5, NOD1 and NOD2 receptor gene expressions and their downstream signaling molecules following thermal stress in the Indian major carp catla (Catla catla)

Toll-like receptors (TLRs) and nucleotide binding and oligomerization domain (NOD) receptors are pattern recognition receptors (PRRs) that recognize pathogen-associated molecular patterns (PAMPs) and play crucial role in innate immunity. In addition to PAMPs, PRRs recognize endogenous molecules released from damaged tissue or dead cells [damage-associated molecular patterns (DAMPs)] and activate signaling cascades to induce inflammatory processes. In the aquatic environment, large variation in seasonal and diurnal water temperature causes heat and cold stresses in fish, resulting in tissue injury and mortality of fish. In the Indian subcontinent, catla (Catla catla) is an economically important freshwater fish species and is prone to thermal stresses. To investigate the response of pattern recognition receptors in thermal stress, we analyzed TLRs (TLR2, TLR4 and TLR5) and NOD (NOD1 and NOD2) receptors gene expression in catla following heat and cold stress. Analysis of tissue samples (gill, liver, kidney and blood) of the thermal stressed and control fish by quantitative real-time PCR (qRT-PCR) assay revealed significant (p < 0.05) induction of TLR2, TLR4 and NOD2 gene expression in majority of the tested tissues of the treated fish as compared to the control. The expression of TLR5 and NOD1 gene was also induced in the heat and cold stressed fish, but mostly restricted in the blood. The downstream signaling molecule of TLR and NOD signaling pathway viz., MyD88 (myeloid differentiation primary response gene 88) and RICK (receptor interacting serine-threonine protein kinase-2) was also induced in the thermal stressed fish suggesting the engagement of TLR and NOD signaling pathway during thermal stress.

A Case of Hereditary Pancreatitis Presenting as Recurrent Abdominal Pain in a 11 Year Old Girl

Recurrent abdominal pain is a common problem among children. Since its first description by John Apley in 1958, the condition has remained poorly understood with a multitude of factors being implicated in causation. The symptoms tend to be vague and investigations seldom show organic disease. But the importance to evaluate each child with recurrent abdominal pain should be considered important nevertheless, particularly, in protracted cases. Here, we present a case who presented with history of recurrent abdominal pain for several years before being diagnosed as a case of hereditary pancreatitis. This stresses the importance of evaluating each case with a detailed and complete history, physical examination and selected investigations.J Nepal Paediatr Soc 2015;35(1):57-58

Characterization and Inductive Expression Analysis of Interferon Gamma-Related Gene in the Indian Major Carp, Rohu (Labeo rohita)

Interferon gamma (IFN-γ) is one of the key cytokines that plays a major role against viral and intracellular bacterial infection. In addition to the IFN-γ gene, teleost fish possess a second copy known as IFN-γ-related (IFN-γrel) gene. This report describes structural and functional properties of IFN-γrel gene in the Indian major carp, rohu (Labeo rohita), a commercially important freshwater fish species in the Indian subcontinent. The rohu IFN-γrel gene consisted of four exons with three intervening introns and phylogenetically closely related to grass carp. The full-length IFN-γrel cDNA comprised 927 bp nucleotides with a single open reading frame of 504 bp, encoding 167 amino acids (aa) polypeptide with a signal peptide of 24 aa. The mature rohu IFN-γrel protein was 143 aa with a predicted molecular weight of 16.85 kDa. Basal expression analysis of IFN-γrel showed its wide range of expression in all examined tissues: The highest was in the skin and the lowest was in the liver. In response to LPS, poly I:C, iE-DAP, muramyl dipeptide stimulations, and bacterial infections, IFN-γrel gene expression was significantly (p<0.05) induced in treated fish tissues as compared with their control. The IFN-γrel was expressed as recombinant protein (rIFN-γrel) and confirmed through western blot. Stimulation of peripheral blood leukocytes with rIFN-γrel protein resulted in the activation of IFN-γ receptor and marked induction of inducible nitric oxide synthase gene expression. These results together may suggest the important role of IFN-γrel as an antimicrobial cytokine in fish.

Salivary biochemical markers as potential acute toxicity parameters for acute radiation injury: A study on small experimental animals

Researchers have been evaluating several biodosimetric/screening approaches to assess acute radiation injury, related to mass causality. Keeping in mind this background, we hypothesized that effect of whole-body irradiation in single fraction in graded doses can affect the secretion of various salivary components that could be used as acute radiation injury/toxicity marker, which can be used in screening of large population at the time of nuclear accidents/disaster. Thirty Sprague Dawley rats treated with whole-body cobalt-60 gamma irradiation of dose 1-5 Gy (dose rate: 0.95 Gy/min) were included in this study. Whole mixed saliva was collected from all animals before and after radiation up to 72 h postradiation. Saliva was analyzed for electrolytes, total protein, urea, and amylase. Intragroup comparison of salivary parameters at different radiation doses showed significant differences. Potassium was significantly increased as the dose increased from 1 Gy to 5 Gy (p < 0.01) with effect size of difference (r > 0.5). Sodium was significantly altered after 3-5 Gy (p < 0.01, r > 0.5), except 1 and 2 Gy, whereas changes in sodium level were nonsignificant (p > 0.5). Urea, total protein, and amylase levels were also significantly increased as the radiation dose increased (p < 0.01) with large effect size of difference (r > 0.5). This study suggests that salivary parameters were sensitive toward radiation even at low radiation dose which can be used as a predictor of radiation injury.

LRRsearch: An asynchronous server-based application for the prediction of leucine-rich repeat motifs and an integrative database of NOD-like receptors

The leucine-rich repeat (LRR) motifs of the nucleotide-binding oligomerization domain like receptors (NLRs) play key roles in recognizing and binding various pathogen associated molecular patterns (PAMPs) resulting in the activation of downstream signaling and innate immunity. Therefore, identification of LRR motifs is very important to study ligand-receptor interaction. To date, available resources pose restrictions including both false negative and false positive prediction of LRR motifs from the primary protein sequence as their algorithms are relied either only on sequence based comparison or alignment techniques or are over biased for a particular LRR containing protein family. Therefore, to minimize the error (≤5%) and to identify a maximum number of LRR motifs in the wide range of proteins, we have developed "LRRsearch" web-server using position specific scoring matrix (PSSM) of 11 residue LRR-HCS (highly conserved segment) which are frequently observed motifs in the most divergent classes of LRR containing proteins. A data library of 421 proteins, distributed among five known NLR families has also been integrated with the "LRRsearch" for the rich user experience. The access to the "LRRsearch" program is freely available at http://www.lrrsearch.com/.

Toll-like receptor 22 in Labeo rohita: molecular cloning, characterization, 3D modeling, and expression analysis following ligands stimulation and bacterial infection

Toll-like receptors (TLRs) are a class of innate immune receptors that sense pathogens or their molecular signatures and activate signaling cascades to induce a quick and non-specific immune response in the host. Among various types of TLRs, TLR22 is exclusively present in teleosts and amphibians and is expected to play the distinctive role in innate immunity. This report describes molecular cloning, three-dimensional (3D) modeling, and expression analysis of TLR22 in rohu (Labeo rohita), the most commercially important freshwater fish species in the Indian subcontinent. The open reading frame (ORF) of rohu TLR22 (LrTLR22) comprised of 2,838 nucleotides (nt), encoding 946 amino acid (aa) residues with the molecular mass of ∼ 107.6 kDa. The secondary structure of deduced LrTLR22 exhibited the presence of signal peptide (1-22 aa), 18 leucine-rich repeat (LRR) regions (79-736 aa), and TIR domain (792-935 aa). The 3D model of LrTLR22-LRR regions together elucidated the horse-shoe-shaped structure having parallel β-strands at the concave surface and few α-helices at the convex surface. The TIR domain structure revealed alternate presence of five α-helices and β-sheets. Phylogenetically, LrTLR22 was closely related to common carp and exhibited significant similarity (92.2 %) and identity (86.1 %) in their amino acids. In rohu, TLR22 was constitutively expressed in all embryonic developmental stages, and tissue-specific analysis illustrated its expression in all examined tissues, highest was in liver and lowest in brain. In vivo modulation of TLR22 gene expression was analyzed by quantitative real-time PCR (qRT-PCR) assay following stimulation with lipopolysaccharide (LPS), synthetic double stranded RNA (polyinosinic-polycytidylic acid), and bacterial (Aeromonas hydrophila) RNA. Among these ligands, bacterial RNA most significantly (p < 0.05) induced TLR22 gene expression in most of the tested tissues. In A. hydrophila infection, induction of TLR22 gene expression was also observed in majority of the tested tissues. Together, these data suggested that in addition to sensing other microbial signatures, TLR22 can recognize bacterial RNA and may play the important role in augmenting innate immunity in fish.

The effect of age on pressure flow parameters in women with lower urinary tract symptoms

This study aimed to evaluate changes in voiding with age in women with different urodynamic diagnoses. Correlation was used to analyse the association between age and voiding parameters (maximum flow rate, voided volume, flow rate centile and maximum detrusor pressure - PdetMax) in 896 datasets. Multivariate analysis was used to analyse the data further by age group and diagnosis - urodynamic stress incontinence (USI); detrusor overactivity (DO); mixed USI and DO; no urodynamic abnormality. Results showed that diagnosis accounts for a significant amount of variation in all four of the dependent variables Age group shows a significant effect on voiding volume but does not show significant effects on any other variable studied. There is no significant interaction term in any of the analyses, meaning that age and diagnosis do not appear to function together, e.g. age does not relate to flow rate centile, maximum flow rate or PdetQMax. It was concluded that the data suggest that there is no significant change in voiding function related to age. In the elderly, the main alteration in voiding is due to a higher prevalence of DO.

Pattern and Determinants of Overweight and Obesity Among Future Physicians

Background   Overweight including obesity is a leading cause of present day morbidity and kills more people than underweight. Keeping this background in mind this study had been conducted to establish the pattern of overweight and obesity in the midst of undergraduate medical group and to find out the association of overweight (plump) and obesity with probable hazardous factors. Materials and Methods This descriptive observational study had been conducted among undergraduate medical group for the duration of May to June 2011. Simple random sampling was adopted to select the students under study. A pretested, predesigned self-administered questionnaire was utilized for data collection. Body Mass Index (BMI) was assessed through weight and height and acted as forecaster of heavy figure and or obesity. Overweight and or obesity were analyzed to see the association with certain socio-demographic variables, dietary habits, family history of overweight and or obesity, life style issues, computer use etc. After collection of data, these were analyzed using tabulation, proportion and Chi square through Epi-Info software. Results The study subjects were young adults. The general pattern of overweight (plump) and obesity was 18.0 percent and 4.0 percent respectively. Overweight and or obesity was found significantly high among male students, fast food and soft drinks takers, low takers of fruits and vegetables, alcohol consumers, students with lack of exercise and family history of obesity. Overweight and obesity were not found associated with type of diet (vegetarian or non-vegetarian) and smoking. Conclusion Presence of probable associated factors with regard to overweight (plump) and obesity exists amid medical undergraduate pupils.DOI: http://dx.doi.org/10.3126/nje.v4i1.10134 Nepal Journal of Epidemiology 2014;4 (1): 323-329

Observational assessment and correlates to blood pressure of future physicians of Bengal

INTRODUCTION

Hypertension is a modern day epidemic and growing public health problem. A sizable proportion of world populations suffer from prehypertension or hypertension.

OBJECTIVES

The present study was carried out to detect the prevalence of undiagnosed hypertension among undergraduate medical students and to identify the associated risk factors.

MATERIALS AND METHODS

The study was observational in nature and was done in medical colleges of Bengal. Study tool was a predesigned, pretested, validated, and semi-structured questionnaire containing both open-ended and close-ended questions. Data were collected through self-administration, clinical, and anthropometric examination. The data were then tabulated, analyzed and interpretation was done by using percentage and Chi-square test.

RESULTS

Most of the students (63%) were young adults, predominantly males (67%) and day scholars (71%). Almost one-third of them either suffered from hypertension or at risk of hypertension. Hypertension was found higher among male students. Family history of hypertension or diabetes mellitus was not associated with hypertension. Vegetarian or nonvegetarian diet or extra-salt consumption was also not associated with hypertension. Smoking was shown positively associated with hypertension but alcohol consumption was not. Higher per capita monthly income and overweight or obesity were shown positively associated with hypertension.

CONCLUSION

The overall prevalence of hypertension in this study was 13% and there were positive association of hypertension with multiple socio-demographic factors like age, sex, type of family, per capita monthly income, residence, BMI, smoking, etc.

Identification of MDP (muramyl dipeptide)-binding key domains in NOD2 (nucleotide-binding and oligomerization domain-2) receptor of Labeo rohita

In lower eukaryotes-like fish, innate immunity contributed by various pattern recognition receptor (PRR) plays an essential role in protection against diseases. Nucleotide-binding and oligomerization domain (NOD)-2 is a cytoplasmic PRR that recognizes MDP (muramyl dipeptide) of the Gram positive and Gram negative bacteria as ligand and activates signalling to induce innate immunity. Hypothesizing a similar NOD2 signalling pathway of higher eukaryotes, the peripheral blood leucocytes (PBLs) of rohu (Labeo rohita) was stimulated with MDP. The data of quantitative real-time PCR (qRT-PCR) revealed MDP-mediated inductive expression of NOD2 and its down-stream molecule RICK/RIP2 (receptor-interacting serine-threonine protein kinase-2). This observation suggested the existence of MDP-binding sites in rohu NOD2 (rNOD2). To investigate it, 3D model of ligand-binding leucine-rich repeat (LRR) region of rNOD2 (rNOD2-LRR) was constructed following ab initio and threading approaches in I-TASSER web server. Structural refinement of the model was performed by energy minimization, and MD (molecular dynamics) simulation was performed in GROMACS (Groningen Machine for Chemical Simulations). The refined model of rNOD2-LRR was validated through SAVES, ProSA, ProQ, WHAT IF and MolProbity servers, and molecular docking with MDP was carried out in GOLD 4.1. The result of docking identified LRR3-7 comprising Lys820, Phe821, Asn822, Arg847, Gly849, Trp877, Trp901 and Trp931 as MDP-binding critical amino acids in rNOD2. This is the first study in fish to provide an insight into the 3D structure of NOD2-LRR region and its important motifs that are expected to be engaged in MDP binding and innate immunity.

Perineal trauma in women undergoing vaginal delivery following intra-uterine fetal demise: a case-control analysis

INTRODUCTION AND HYPOTHESIS

This study aimed to evaluate any differences in the incidence of perineal trauma in women undergoing vaginal delivery following intrauterine fetal death (IUFD) versus live-births. This information would be of interest in evaluating the possible effect of fetal demise on the mechanism of labour in the second stage and thus may provide invaluable insights to contribute to our understanding of the impact of fetal tone on the mechanics of labour and delivery.

METHODS

323 women who delivered vaginally following IUFD were matched with 1,000 women with a live-birth for age, parity, gestation and birth weight. Women undergoing assisted vaginal delivery and/or episiotomy were excluded.

RESULTS

Women with an IUFD had a significantly lower risk of perineal trauma overall (relative risk 0.16) as well as a lower risk of obstetric anal sphincter injury specifically (RR 0.12).

CONCLUSIONS

Women delivering vaginally after IUFD have a lower incidence of perineal trauma compared with women delivering a live infant. This may be due to differences in biomechanics following an IUFD.