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India is hyperendemic to dengue virus and over 50% of the adults are seropositive but there is limited information on the association between prior dengue exposure with neutralizing antibody profiles and how this could influence virus evolution and vaccine development. In this work, we found that the dengue seropositivity increased with age and pre-existing antibody levels negatively correlated with viremia during acute phase of illness. Adults showed a higher levels of viremia which associated with lower levels of neutralizing antibodies as compared to children. The titers of neutralizing antibodies negatively influenced the dominance of circulating dengue serotypes with highest levels of the neutralizing antibodies against DENV-2 followed by DENV-1, DENV-3 and DENV-4. We observed minimal cross-reactivity of neutralizing antibodies with related flaviviruses such as Japanese encephalitis virus and West Nile virus and the antibodies elicited against Indian isolates show a reduced ability to neutralize international dengue isolates.

India was severely affected by several waves of SARS-CoV-2 infection that occurred during April-June 2021 (second wave) and December 2021-January 2022 (third wave) and thereafter, resulting in 10 million new infections and a significant number of deaths. Global Initiative on Sharing Avian Influenza Data database was used to collect the sequence information of ~10,000 SARS-CoV-2 patients from India and our sequence analysis identified three variants B.1.1.7 (alpha, α), B1.617.2 (delta, Δ), B.1.1.529 (Omicron, Oo) and one Omicron sub-variant BA.2.75 as the primary drivers for SARS-CoV-2 waves in India. Structural visualization and analysis of important mutations of alpha, delta, Omicron and its sub-variants of SARS-CoV-2 Receptor-Binding Domain (RBD) was performed and our analysis clearly shows that mutations occur throughout the RBD, including the RBD surface responsible for human angiotensin-converting enzyme 2 (hACE-2) receptor-binding. A comparison between alpha, delta and omicron variants/sub-variants reveals many omicron mutations in the hACE-2 binding site and several other mutations within 5 Å of this binding region. Further, computational analysis highlights the importance of electrostatic interactions in stabilizing RBD-hACE-2-binding, especially in the omicron variant. Our analysis explores the likely role of key alpha, delta and omicron mutations on binding with hACE-2. Taken together, our study provides novel structural insights into the implications of RBD mutations in alpha, delta and omicron and its sub-variants that were responsible for India's SARS-CoV-2 surge.

A detailed understanding of the molecular features of the neutralizing epitopes developed by viral escape mutants is important for predicting and developing vaccines or therapeutic antibodies against continuously emerging SARS-CoV-2 variants. Here, we report three human monoclonal antibodies (mAbs) generated from COVID-19 recovered individuals during first wave of pandemic in India. These mAbs had publicly shared near germline gene usage and potently neutralized Alpha and Delta, but poorly neutralized Beta and completely failed to neutralize Omicron BA.1 SARS-CoV-2 variants. Structural analysis of these three mAbs in complex with trimeric spike protein showed that all three mAbs are involved in bivalent spike binding with two mAbs targeting class-1 and one targeting class-4 Receptor Binding Domain (RBD) epitope. Comparison of immunogenetic makeup, structure, and function of these three mAbs with our recently reported class-3 RBD binding mAb that potently neutralized all SARS-CoV-2 variants revealed precise antibody footprint, specific molecular interactions associated with the most potent multi-variant binding / neutralization efficacy. This knowledge has timely significance for understanding how a combination of certain mutations affect the binding or neutralization of an antibody and thus have implications for predicting structural features of emerging SARS-CoV-2 escape variants and to develop vaccines or therapeutic antibodies against these.

In this study, by characterizing several human monoclonal antibodies (mAbs) isolated from single B cells of the COVID-19–recovered individuals in India who experienced ancestral Wuhan strain (WA.1) of SARS-CoV-2 during early stages of the pandemic, we found a receptor binding domain (RBD)–specific mAb 002-S21F2 that has rare gene usage and potently neutralized live viral isolates of SARS-CoV-2 variants including Alpha, Beta, Gamma, Delta, and Omicron sublineages (BA.1, BA.2, BA.2.12.1, BA.4, and BA.5) with IC 50 ranging from 0.02 to 0.13 μg/ml. Structural studies of 002-S21F2 in complex with spike trimers of Omicron and WA.1 showed that it targets a conformationally conserved epitope on the outer face of RBD (class 3 surface) outside the ACE2-binding motif, thereby providing a mechanistic insights for its broad neutralization activity. The discovery of 002-S21F2 and the broadly neutralizing epitope it targets have timely implications for developing a broad range of therapeutic and vaccine interventions against SARS-CoV-2 variants including Omicron sublineages.

Previous studies showed that a discrete population of the CD8 T cells with HLADR+CD38+ phenotype expand massively during the acute febrile phase of dengue natural infection. Although about a third of these massively expanding HLADR+CD38+ CD8 T cells were of CD69high phenotype, only a small fraction of them produced IFNγ upon in vitro peptide stimulation. What other cytokines/ chemokines do these peptides stimulated HLADR+CD38+ CD8 T cells express, what transcriptional profiles distinguish the CD69+IFNγ+, CD69+IFNγ-, and CD69-IFNγ- subsets, and whether the expansion of the total HLADR+CD38+ CD8 T cells or the IFNγ producing CD8 T cells differ depending on disease severity remained unclear. This study addresses these knowledge gaps. We find that the CD69+IFNγ+ subset uniquely expressed key genes involved in protein translation, cellular metabolism, proliferation and dendritic cell cross talk. Both the CD69+IFNγ+ and CD69+IFNγ- subsets had an antigen responsive gene signature with genes involved in cytotoxic effector functions, regulation of T cell receptor signaling, signaling by MAPK, chemotaxis and T cell trafficking to inflamed tissues with the expression being more robust in the IFNγ+ CD69+ subset. On the other hand, the CD69- IFNγ- subset was biased towards expression of genes that both augment and dampen T cell responses. Lastly, the expansion of total HLADR+ CD38+ CD8 T cells and also the IFNγ producing HLADR+ CD38+ CD8 T cells was similar in patients with different grades of disease. Taken together, this study provides valuable insights into the inherent diversity of the effector CD8 T cell response during dengue.

Chikungunya virus (CHIKV), an arthropod-borne Alphavirus is responsible for chikungunya disease. Arthralgia and arthritis are the major symptom. Some patients recover early while others for a very long time. This study provides, epidemiology and molecular characterization of three whole-genome sequences of CHIKV and assessed phylogenetic analysis, physiological properties, antigenicity, and B-cell epitope prediction by in silico. We report the clinical epidemiology of 325 suspected patients. Of these, 118 (36.30%) were confirmed CHIKV positive by either PCR or ELISA. Clinical analysis showed joint pain, joint swelling and headache were frequent and significant features. Phylogenie analysis showed the currently circulating strain is in close clustring to Africa, Uganda, and Singapore CHIKV strains. Molecular characterization by WGS was done. Thirty eight amino acid changes in the nonstructural proteins were found with respect to the S27 (ECSA) strain. Of these five located in nsP2. Similarly, 34 amino acid changes in structural proteins were observed. The major change was notice; in E3 protein hydropathicity -0.281 to -0.362, in E2 isoelectric point (pI) 8.24 to 8.37, instability index 66.08 to 71.062, aliphatic index varied from 74.69 to 68.59 and E3 75.79 to 70.05. In nsP1 protein pI varies from 6.62 to 8.04, while no other change was observed in structural and nonstructural protein. The linear B-cell epitopes, position, and number varied with the mutation. The molecular characterizations of WGS demonstrate the observation of protein, antigenicity with respect to the mutation.

India is one of the most affected countries by COVID-19 pandemic; but little is understood regarding immune responses to SARS-CoV-2 in this region. Herein we examined SARS-CoV-2 neutralizing antibodies, IgG, IgM, IgA and memory B cells in COVID-19 recovered individual from India. While a vast majority of COVID-19 recovered individuals showed SARS-CoV-2 RBD-specific IgG, IgA and IgM antibodies (38/42, 90.47%; 21/42, 50%; 33/42, 78.57% respectively), only half of them had appreciable neutralizing antibody titers. RBD-specific IgG, but not IgA or IgM titers, correlated with neutralizing antibody titers and RBD-specific memory B cell frequencies. These findings have timely significance for identifying potential donors for plasma therapy using RBD-specific IgG assays as surrogate measurement for neutralizing antibodies in India. Further, this study provides useful information needed for designing large-scale studies towards understanding of inter-individual variation in immune memory to SARS CoV-2 natural infection for future vaccine evaluation and implementation efforts.

Dengue and Chikungunya are two major arboviral infections transmitted worldwide by the mosquitoes, Aedes aegypti and Ae. albopictus. India suffers enormously with both Dengue and Chikungunya as they pose a great public health challenge. The present study aims to evaluate the prevalence of Dengue Virus (DENV), Chikungunya Virus (CHIKV) and DENV/CHIKV co-infection (by Reverse-Transcriptase Polymerase Chain Reaction (RT-PCR)/Enzyme Linked Immunosorbent Assay (ELISA), their clinical features, DENV serotypes and CHIKV specific Immunoglobulin G (IgG) within a 7 years gap in the Delhi population. The study sample included clinically suspected febrile patients (?7 days) sera collected during 2017-2018 (n=87) and during 2008-2010 (n=623) from Delhi. Captured ELISA was performed for CHIKV IgG screening and nested PCR was done for DENV serotyping. The percentage prevalence for DENV was significantly higher than CHIKV with 41.38% (n=87) and 16.1% (n=87), respectively; interestingly, DENV/CHIKV co-infection was detected in 10.34% (n=9/87) cases during 2017-2018. Similarly, a high DENV prevalence was observed during 2008-2010 with the prevalence rate of 38.3% (69/180), 34.65% (35/101) and 47.07% (161/342), respectively. DENV 1 and DENV 3 were dominant serotype during 2008-2010 and 2017-2018 respectively. We have noticed a high prevalence (36.67%, 22/60) of the CHIKV IgG antibody in the 2017-2018 samples. Joint pain was more preferential to CHIKV mono-infection and DENV/CHIKV co-infection compared to DENV mono-infection. The present study highlights the need for active surveillance simultaneously for both DENV and CHIKV and to evaluate the role of CHIKV/DENV co-infections in disease severity in the endemic regions.

Chikungunya virus (CHIKV) infection is endemic in many different countries. CHIKV outbreaks are emerging in new areas and re-emerging in previously exposed geographical regions, thus making it a significant public health concern. CHIKV infections are often clinically inapparent, especially in children, which poses a challenge to testing and evaluating any vaccine. During CHIKV infection, CHIKV-specific antibodies are produced, and some of these antibodies can neutralize viruses released from infected cells before they can enter uninfected cells. In this study, we evaluated IgG binding and neutralizing antibody responses in paired serum samples from CHIKV-infected children and those with other febrile illness, using a recombinant truncated E2 protein and whole CHIKV particles as test antigens. Antibody detection using the truncated E2 protein showed a significant overlap between CHIKV-infected subjects and those with other febrile illnesses. This overlap was greater when binding antibody titers were determined using fixed CHIKV particles as the test antigen. Acute- and convalescent-phase sera collected from children after CHIKV infection showed significant differences in their neutralizing capacity. The neutralizing and binding antibody response showed a significant positive correlation. We detected IgG antibodies in most cases during the acute phase of infection. This was observed at two different geographical locations, one of which is not considered highly endemic. Conventional wisdom would suggest this to be a marker of re-infection (secondary infection). However, dissenting opinions have been voiced in other viral diseases (such as Ebola) where studies have detected IgG in acute illness. In the absence of any significant body of work documenting secondary CHIKV infections, we believe further work is needed to understand the early IgG response that we observed.

With explosive epidemics of chikungunya in India since 2004, chikungunya virus (CHIKV) now co-circulates in geographical areas where Dengue virus (DENV) is already endemic and thus provides opportunity for the same mosquito to be infected with both viruses. Although there are excellent studies that have addressed the clinical of mono and co-infection, we have little to no knowledge on the current viral sequences that pre-dominate co-infections, and the B cell response elicited. In this study, we analyzed febrile patients that were confirmed to have DENV-CHIKV co-infections and asked the following questions: 1) what is the frequency of co-infections found in a single cycle of transmission; 2) what are the viral sequences associated with them; 3) what does the antibody secreting cell / plasmablast response look like in patients that are co-infected with both viruses. We report those co-infections occur at a frequency of 6.7% in the transmission cycle, and while DENV-3 is now frequently detected, we do not see a serotype bias in the patients that are co-infected with ESCA strain of CHIKV. Moreover, the effector B cell response (plasmablasts) observed are specific to both infecting viruses indicating no overt bias. Further studies to associate whether any of these properties have a bearing on clinical disease manifestation will be both timely and important.

The SARS-CoV-2 BA.1 and BA.2 (Omicron) variants contain more than 30 mutations within the spike protein and evade therapeutic monoclonal antibodies (mAbs). Here, we report a receptor-binding domain (RBD) targeting human antibody (002-S21F2) that effectively neutralizes live viral isolates of SARS-CoV-2 variants of concern (VOCs) including Alpha, Beta, Gamma, Delta, and Omicron (BA.1 and BA.2) with IC50 ranging from 0.02 – 0.05 μg/ml. This near germline antibody 002-S21F2 has unique genetic features that are distinct from any reported SARS-CoV-2 mAbs. Structural studies of the full-length IgG in complex with spike trimers (Omicron and WA.1) reveal that 002-S21F2 recognizes an epitope on the outer face of RBD (class-3 surface), outside the ACE2 binding motif and its unique molecular features enable it to overcome mutations found in the Omicron variants. The discovery and comprehensive structural analysis of 002-S21F2 provide valuable insight for broad and potent neutralization of SARS-CoV-2 Omicron variants BA.1 and BA.2.

Over the past two decades, many countries that have reported a steady decline in reported cases of malaria and a few countries like China have been declared malaria-free by the World Health Organization. In 2020, global total malaria cases 108 malaria-endemic countries as in 2000, while the number of deaths from malaria has declined since 2000. COVID-19 pandemic has adversely affected overall public health efforts and thus it is feasible that there might be resurgence of malaria. COVID-19 and malaria share some similarities in the immune responses of the patient and these two diseases also share overlapping early symptoms such as fever, headache, nausea, and muscle pain/fatigue. In the absence of early diagnostics there can be a misdiagnosis of the infection(s) that can pose additional challenges due to delayed treatment. In both SARS-CoV-2 and Plasmodium infections there is a rapid release of cytokines/chemokines that play a key role in disease pathophysiology. In this review, we have discussed the cytokine/chemokine storm observed during COVID-19 and malaria. We observe that: (1) Severity in malaria and COVID-19 is likely a consequence primarily of an uncontrolled 'cytokine storm'; (2) five pro-inflammatory cytokines (IL-6, IL-10, TNF-α, type I IFN and IFN-γ) are significantly increased in severe/critically ill patients in both diseases; (3) Plasmodium and SARS-CoV-2 share some similar clinical manifestations and thus may result in fatal consequences if misdiagnosed during onset.

Monocytes are known to play a critical role in dengue pathophysiology. However, which monocyte subset expresses what inflammatory mediator(s) and what transcriptional features distinguish each of the monocyte subset

Previous studies have shown that plasmablasts expand massively in dengue patients as compared to many other situations such as influenza infection or vaccination. However, a detailed understanding of the phenotypes and transcriptional features of these cells is lacking. Moreover, despite India having nearly a third of global dengue disease burden, there is virtually no information on plasmablasts responses in dengue patients from India. Here, we provide a detailed characterization of plasmablast responses from dengue confirmed febrile children in India. Immunophenotyping and RNA seq analysis showed that in addition to secreting dengue specific antibodies, these massively expanding cells expressed several adhesion molecules, chemokines and chemokine receptors that are involved in endothelial interactions, homing to skin or mucosal tissues including intestine. Surprisingly, we found that these cells also upregulated expression of several cytokine genes that are involved in angiogenesis, leukocyte extravasation and vascular permeability. These transcriptional features were qualitatively similar to plasmablasts from influenza vaccinees. Interestingly, the expansion of the plasmablasts in dengue patients was significantly lower in patients with primary dengue infection compared to those with secondary dengue. Moreover, within the primary dengue patients, their expansion was significantly lower in patients with mild dengue infection (DI) compared to patients with dengue with warning signs (DW) or severe dengue (SD). These results significantly improve our understanding of human plasmablast responses in dengue.ImportanceDengue is a globally spreading with over 100 million clinical cases annually with symptoms ranging from mild self-limiting febrile illness to more severe and sometimes life-threatening dengue hemorrhagic fever or shock, especially among children. India contributes nearly a third of global dengue disease burden. The pathophysiology of dengue is complex and remains poorly understood despite many advances indicating a key role for antibody dependent enhancement of infection. While serum antibodies have been extensively studied, the characteristics of the cellular factories responsible for antibody production, i.e., plasmablasts, are only beginning to emerge. This study provides a comprehensive understanding of the magnitude, phenotype, functional and transcriptional profiles of human plasmablasts from dengue patients in India.

Objectives: To genotypically characterize dengue virus (DENV) isolates among dengue-infected children from 2012–13/2014–15 outbreaks in southern India. Methods: Children hospitalized with suspected dengue were tested for dengue RT-PCR targeting Capsid-preMembrane (C-prM) and Envelope (Env) regions. Following virologic confirmation (n = 612), a representative selection of DENV isolates (n = 99) were sequenced for C-prM, aligned using ClustalW and subjected to phylogenetic analysis by maximum-likelihood method in MEGA6. Results: In 2012–13 (n = 113), DENV-3 (44, 38.9%) and DENV-2 (43, 38.1%) predominated; DENV-1 (22, 19.5%) and DENV-4 (1, 0.9%) were less common. The pattern changed in 2014–15 (n = 499), when DENV-1 (329, 65.7%) predominated, followed by DENV-2 (97, 21.2%), DENV-3 (36, 6.7%) and DENV-4 (10, 2.0%). Multiple-serotype co-infections occurred in 2.7% and 5.4% in 2012–13 and 2014–15, respectively. Genotype III (GIII) of DENV-1 predominated (85.7%) in 2012–13, ceding to GI predominance (80.8%) in 2014–15. Among DENV-2, 71.9% (23/32) showed distinct clustering suggesting a new lineage, ‘GIVc’. All tested DENV-4 were GIC, whose clustering pattern showed the emergence of two distinct clades. Conclusions: New genotypic/lineage variations in DENV-1 and DENV-2 may have influenced the magnitude and severity of dengue epidemics in southern India during this period. These findings emphasize the role of active surveillance of DENV serotypes/genotypes in aiding outbreak control and vaccine studies. Keywords: Dengue virus, Serotyping, Sequencing, Phylogenetics, Genotypes, Lineages

While evidence suggests a division between two qualitatively distinct forms of dissociation, no scale has been specifically designed to differentiate between them. This study describes the development and validation of the Detachment and Compartmentalization Inventory (DCI). The DCI was developed from dissociation theory, 29 existing dissociation scales and expert opinion. An initial pilot study was conducted which assessed readability, explored validity and reduced items before the DCI was administered online to 89 nonclinical and 105 clinical participants. The Dissociative Experiences Scale (DES), Somatoform Dissociation Questionnaire (SDQ), and Mindfulness Attention Awareness Scale (MAAS) were included in the survey battery. The DCI exhibited good internal reliability, discriminant validity, convergent validity, construct validity and concurrent validity. The final version containing 22-items, is self-administered, grounded in the theoretical literature and supported by initial psychometric evaluation. It has 10 items assessing compartmentalization, 10 items assessing detachment and two items examining valid responding. The DCI could detect compartmentalization and detachment, and was designed for clinical research and for screening patients.

Glutaredoxins (Grxs) are single-domain redox enzymes of the thioredoxin superfamily, and primarily function as glutathione (GSH) dependent disulphide reductases. Whereas, the E. coli Glutaredoxin 2 (EcGrx2) encoded by grxB has two conserved GST-fold domains, it still lacks a classical Grx-like functions. In this study, we show for the first time, that EcGrx2 exists in both soluble and membrane integrated forms. The soluble form associates with a previously unidentified GSH dependent dehydroascrobate (DHA) reductase, and the membrane integrated form possesses ion channel activities. Using enzyme kinetic data and structural data we unequivocally demonstrate that EcGrx2 recycles ascorbate (AsA) from DHA. This ability to recycle AsA is inhibited by Zinc (Zn2+). We also show that both wildtype and the E. coli grxB deletion mutant can be rescued from H2O2-induced oxidative stress using ascorbate as an antioxidant, which otherwise is only known as a carbon source in bacteria. Moreover, the grxB- mutant is susceptible to intracellular killing by ROS producing macrophages. We further discovered that EcGrx2 integrates into the native E. coli membrane and show that the purified soluble protein readily inserts into artificial lipid bilayer membrane and conducts ions in vitro. Our data demonstrates a highly conserved functional similarity among EcGrx2-orthologs and highlights that the utilization and subsequent recycling of ascorbate as an antioxidant by grxB harbouring gram-negative bacteria, including human pathogens, may provide a survival advantage under hostile oxidative environments.

Dengue is emerging as one of the most prevalent mosquito-borne viral diseases of humans. The 11kb RNA genome of the dengue virus encodes three structural proteins (envelope, pre-membrane, capsid) and seven non-structural proteins (NS1, NS2A, NS2B, NS3, NS4A, NS4B, and NS5), all of which are translated as a single polyprotein that is subsequently cleaved by viral and host cellular proteases at specific sites. Non-structural protein 5 (NS5) is the largest of the non-structural proteins, functioning as both an RNA-dependent RNA polymerase (RdRp) that replicates the viral RNA and an RNA methyltransferase enzyme (MTase) that protects the viral genome by RNA capping, facilitating polyprotein translation. Within the human host, NS5 interacts with several proteins such as those in the JAK-STAT pathway, thereby interfering with anti-viral interferon signalling. This mini-review presents annotated, consolidated lists of known and potential NS5 interactors in the human host as determined by experimental and computational approaches respectively. The most significant protein interactors and the biological pathways they participate in are also highlighted and their implications discussed, along with the specific serotype of dengue virus as appropriate. This information can potentially stimulate and inform further research efforts towards providing an integrative understanding of the mechanisms by which NS5 manipulates the human-virus interface in general and the innate and adaptive immune responses in particular.

Amnesia is a core diagnostic criterion for Dissociative Identity Disorder (DID), however previous research has indicated memory transfer. As DID has been conceptualised as being a disorder of distinct identities, in this experiment, behavioral tasks were used to assess the nature of amnesia for episodic 1) self-referential and 2) autobiographical memories across identities. Nineteen DID participants, 16 DID simulators, 21 partial information, and 20 full information comparison participants from the general population were recruited. In the first study, participants were presented with two vignettes (DID and simulator participants received one in each of two identities) and asked to imagine themselves in the situations outlined. The second study used a similar methodology but with tasks assessing autobiographical experience. Subjectively, all DID participants reported amnesia for events that occurred in the other identity. On free recall and recognition tasks they presented a memory profile of amnesia similar to simulators instructed to feign amnesia and partial information comparisons. Yet, on tests of recognition, DID participants recognized significantly more of the event that occurred in another identity than simulator and partial information comparisons. As such, results indicate that the DID performance profile was not accounted for by true or feigned amnesia, lending support to the idea that reported amnesia may be more of a perceived than actual memory impairment.

India is one of the countries most affected by the recent COVID-19 pandemic. Characterization of humoral responses to SARS-CoV-2 infection, including immunoglobulin isotype usage, neutralizing activity and memory B cell generation, is necessary to provide critical insights on the formation of immune memory in Indian subjects. In this study, we evaluated SARS-CoV-2 receptor-binding domain (RBD)-specific IgG, IgM, and IgA antibody responses, neutralization of live virus, and RBD-specific memory B cell responses in pre-pandemic healthy versus convalescent COVID-19 individuals from India. We observed substantial heterogeneity in the formation of humoral and B cell memory post COVID-19 recovery. While a vast majority (38/42, 90.47%) of COVID-19 recovered individuals developed SARS-CoV-2 RBD-specific IgG responses, only half of them had appreciable neutralizing antibody titers. RBD-specific IgG titers correlated with these neutralizing antibody titers as well as with RBD-specific memory B cell frequencies. In contrast, IgG titers measured against SARS-CoV-2 whole virus preparation, which includes responses to additional viral proteins besides RBD, did not show robust correlation. Our results suggest that assessing RBD-specific IgG titers can serve as a surrogate assay to determine the neutralizing antibody response. These observations have timely implications for identifying potential plasma therapy donors based on RBD-specific IgG in resource-limited settings where routine performance of neutralization assays remains a challenge.ImportanceOur study provides an understanding of SARS-CoV-2-specific neutralizing antibodies, binding antibodies and memory B cells in COVID-19 convalescent subjects from India. Our study highlights that PCR-confirmed convalescent COVID-19 individuals develop SARS-CoV-2 RBD-specific IgG antibodies, which correlate strongly with their neutralizing antibody titers. RBD-specific IgG titers, thus, can serve as a valuable surrogate measurement for neutralizing antibody responses. These finding have timely significance for selection of appropriate individuals as donors for plasma intervention strategies, as well as determining vaccine efficacy.

Our understanding of human immune responses is increasing at an unprecedented scale. Cutting edge new technologies are allowing us to disregard a piecemeal approach and analyze human immune responses in a comprehensive and cohesive manner. Innovative approaches to analyze immune cell phenotype, genotype, function, and associated soluble factors have provided us with a new hope for making vaccines against diseases that have been historically impossible. This review recaps a few state-of-the-art tools and technologies that have helped us harness the power of human immunology for vaccine design, evaluation, and testing.

Introduction: Osteoporosis is the leading challenge for orthopaedic surgeons and its burden is increasing very fast. This study is conducted in the Vidarbha region of Maharashtra to know the epidemiology and effect of environmental factors on osteoporosis.Material and Methods: It’s an observational study conducted on 3287 women with age above 45 years. These patients were selected from the nine districts of Vidarbha region in Maharashtra. The assessment of bone density was done by using quantitative ultrasound technique at heel. Results: Overall prevalence of osteoporosis in Vidarbha region in women above 45 years age was 43.33%. The prevalence was highest among executive job group (55.2%) and least among tribal women (31.08%). Education and literacy level does not influence the occurrence of osteoporosis.Conclusion: The prevalence of osteoporosis is rising very fast with increase in sedentary life style and nutritional hazards. Environmental factors clearly impact the occurrence of osteoporosis in different subset of population.

Dengue virus (DENV) is most prevalent arthropod-borne human pathogen belongs to Flaviviridae family causes thousands of deaths annually. HMGB1 is highly conserved, ubiquitously expressed, non-histone nuclear protein which plays important role in diseases like metabolic disorders, cancer, and viral infections. However, the importance of HMGB1 in DENV infection is understudied. In this study, we observed that DENV-2 induces cytoplasmic translocation and secretion of HMGB1. Interestingly, inhibition of HMGB1 secretion by ethyl pyruvate (EP) enhanced viral propagation while silencing of HMGB1 resulted in abrogated viral replication in DENV-2 infected A549 cells. RNA-Electrophoretic mobility shift assay and immunoprecipitation showed that HMGB1 interacts with 5'-3' UTRs of DENV-2 genome. This interaction further stimulates production of proinflammatory cytokines like TNF-α, IL-6 and IL-1β which have been implicated in pathogenesis of severe DENV disease. Together, our finding suggests that DENV-2 modulates HMGB1 translocation and HMGB1-DENV-2 UTRs RNA interaction further induces proinflammatory cytokines production in A549 cells. This study discloses HMGB1 as an important host factor contributing to disease pathogenesis and hence can be targeted as an alternative approach for antiviral development against DENV virus infection.

Dengue surveillance relies on reverse transcription-polymerase chain reaction (RT-PCR), for confirmation of dengue virus (DENV) serotypes. We compared efficacies of published and modified primer sets targeting envelope (Env) and capsid-premembrane (C-prM) genes for detection of circulating DENV serotypes in southern India. Acute samples from children with clinically-diagnosed dengue were used for RT-PCR testing. All samples were also subjected to dengue serology (NS1 antigen and anti-dengue-IgM/IgG rapid immunochromatographic assay). Nested RT-PCR was performed on viral RNA using three methods targeting 654bp C-prM, 511bp C-prM and 641bp Env regions, respectively. RT-PCR-positive samples were validated by population sequencing. Among 171 children with suspected dengue, 121 were dengue serology-positive and 50 were dengue serology-negative. Among 121 serology-positives, RT-PCR detected 91 (75.2%) by CprM654, 72 (59.5%) by CprM511, and 74 (61.1%) by Env641. Among 50 serology-negatives, 10 (20.0%) were detected by CprM654, 12 (24.0%) by CprM511, and 11 (22.0%) by Env641. Overall detection rate using three methods sequentially was 82.6% (100/121) among serology-positive and 40.0% (20/50) among serology-negative samples; 6.6% (8/120) had co-infection with multiple DENV serotypes. We conclude that detection of acute dengue was enhanced by a modified RT-PCR method targeting the 654bp C-prM region, and further improved by using all three methods sequentially.

Chikungunya virus (CHIKV) infection is endemic in many different countries. CHIKV outbreaks are emerging in new areas and re-emerging in previously exposed geographical regions, thus making it a significant public health concern. CHIKV infections are often clinically inapparent, especially in children, which poses a challenge to testing and evaluating any vaccine. During CHIKV infection, CHIKV-specific antibodies are produced, and some of these antibodies can neutralize viruses released from infected cells before they can enter uninfected cells. In this study, we evaluated IgG binding and neutralizing antibody responses in paired serum samples from CHIKV-infected children and those with other febrile illness, using a recombinant truncated E2 protein and whole CHIKV particles as test antigens. Antibody detection using the truncated E2 protein showed a significant overlap between CHIKV-infected subjects and those with other febrile illnesses. This overlap was greater when binding antibody titers were determined using fixed CHIKV particles as the test antigen. Acute- and convalescent-phase sera collected from children after CHIKV infection showed significant differences in their neutralizing capacity. The neutralizing and binding antibody response showed a significant positive correlation. We detected IgG antibodies in most cases during the acute phase of infection. This was observed at two different geographical locations, one of which is not considered highly endemic. Conventional wisdom would suggest this to be a marker of re-infection (secondary infection). However, dissenting opinions have been voiced in other viral diseases (such as Ebola) where studies have detected IgG in acute illness. In the absence of any significant body of work documenting secondary CHIKV infections, we believe further work is needed to understand the early IgG response that we observed.

Objective: To characterize the in vitro replication fitness, viral diversity, and phylogeny of dengue viruses (DENV) isolated from Indian patients. Methods: DENV was isolated from whole blood collected from patients by passaging in cell culture. Passage 3 viruses were used for growth kinetics in C6/36 mosquito cells. Parallel efforts also focused on the isolation of DENV RNA from plasma samples of the same patients, which were processed for next-generation sequencing. Results: It was possible to isolate 64 clinical isolates of DENV, mostly DENV-2. Twenty-five of these were further used for growth curve analysis in vitro, which showed a wide range of replication kinetics. The highest viral titers were associated with isolates from patients with dengue with warning signs and severe dengue cases. Full genome sequences of 21 DENV isolates were obtained. Genome analysis mapped the circulating DENV-2 strains to the Cosmopolitan genotype. Conclusions: The replication kinetics of isolates from patients with mild or severe infection did not differ significantly, but the viral titers varied by two orders of magnitude between the isolates, suggesting differences in replication fitness among the circulating DENV-2. Keywords: Dengue virus, Growth curve, Phylogenetics, Genotype, Mutations

Chikungunya virus (CHIKV) infection causes acute febrile illness in humans, and some of these individuals develop a debilitating chronic arthritis that can persist for months to years for reasons that remain poorly understood. In this study from India, we characterized antibody response patterns in febrile chikungunya patients and further assessed the association of these initial febrile-phase antibody response patterns with protection versus progression to developing chronic arthritis. We found 5 distinct patterns of the antibody responses in the febrile phase: no CHIKV binding or neutralizing (NT) antibodies but PCR positive, IgM alone with no NT activity, IgM alone with NT activity, IgM and IgG without NT activity, and IgM and IgG with NT activity. A 20-month follow-up showed that appearance of NT activity regardless of antibody isotype or appearance of IgG regardless of NT activity during the initial febrile phase was associated with a robust protection against developing chronic arthritis in the future. These findings, while providing potentially novel insights on correlates of protective immunity against chikungunya-induced chronic arthritis, suggest that qualitative differences in the antibody response patterns that have evolved during the febrile phase can serve as biomarkers that allow prediction of protection or progression to chronic arthritis in the future.

Introduction: To evaluate the functional outcome in bony Posterior Cruciate Ligament (PCL) avulsion fractures treated with open reduction and internal fixation through Mini open technique. The approach is safe, and simple with a slight modification and technical tips. Material and Methods: Twenty four patients (19 males and 5 females) were included in the study. Fixation was done through a modified mini open technique using 4 mm cannulated cancellous screws. The minimum follow up considered in study was one year. Functional outcome was assessed using clinical examination, Tegner Lysholm knee score and stress radiography. Results: The mean Tegner Lysholm scores at the time of 1 year follow up was 91.66. The PCL laxity assessed clinically by posterior drawer test on stress radiography was grade I in 3 cases and nil in rest of 21 at 8 weeks follow-up. All the patients had achieved bony union of tibial avulsion fractures at the time of last follow up. Conclusion: Bony PCL avulsion fractures treated by Mini open technique with open reduction and internal fixation achieved good to excellent results and can prevent significant late onset disability.

Epidemiological studies suggest that India has the largest number of dengue virus infection cases worldwide. However, there is minimal information about the immunological responses in these patients. CD8 T cells are important in dengue, because they have been implicated in both protection and immunopathology. Here, we provide a detailed analysis of HLA-DR + CD38 + and HLA-DR − CD38 + effector CD8 T cell subsets in dengue patients from India and Thailand. Both CD8 T cell subsets expanded and expressed markers indicative of antigen-driven proliferation, tissue homing, and cytotoxic effector functions, with the HLA-DR + CD38 + subset being the most striking in these effector qualities. The breadth of the dengue-specific CD8 T cell response was diverse, with NS3-specific cells being the most dominant. Interestingly, only a small fraction of these activated effector CD8 T cells produced gamma interferon (IFN-γ) when stimulated with dengue virus peptide pools. Transcriptomics revealed downregulation of key molecules involved in T cell receptor (TCR) signaling. Consistent with this, the majority of these CD8 T cells remained IFN-γ unresponsive even after TCR-dependent polyclonal stimulation (anti-CD3 plus anti-CD28) but produced IFN-γ by TCR-independent polyclonal stimulation (phorbol 12-myristate 13-acetate [PMA] plus ionomycin). Thus, the vast majority of these proliferating, highly differentiated effector CD8 T cells probably acquire TCR refractoriness at the time the patient is experiencing febrile illness that leads to IFN-γ unresponsiveness. Our studies open novel avenues for understanding the mechanisms that fine-tune the balance between CD8 T cell-mediated protective versus pathological effects in dengue. IMPORTANCE Dengue is becoming a global public health concern. Although CD8 T cells have been implicated both in protection and in the cytokine-mediated immunopathology of dengue, how the balance is maintained between these opposing functions remains unknown. We comprehensively characterized CD8 T cell subsets in dengue patients from India and Thailand and show that these cells expand massively and express phenotypes indicative of overwhelming antigenic stimulus and tissue homing/cytotoxic-effector functions but that a vast majority of them fail to produce IFN-γ in vitro . Interestingly, the cells were fully capable of producing the cytokine when stimulated in a T cell receptor (TCR)-independent manner but failed to do so in TCR-dependent stimulation. These results, together with transcriptomics, revealed that the vast majority of these CD8 T cells from dengue patients become cytokine unresponsive due to TCR signaling insufficiencies. These observations open novel avenues for understanding the mechanisms that fine-tune the balance between CD8-mediated protective versus pathological effects.

Introduction: Bilateral anterior column acetabulum fractures in literature have been reported due to osteoporosis and seizure disorders. Very few cases have been reported after road traffic accident (RTA) and that too in a young patient without osteoporosis. We present a similar case in a young patient following a high-velocity injury managed with open reduction and internal fixation (ORIF). Case Report: A 28-year-old male presented with bilateral anterior column acetabulum fracture following RTA. The patient was initially admitted to emergency and stabilized hemodynamically. He was operated later with ORIF on both sides using ilioinguinal approach. At 1-year follow-up, the patient is able to walk, squat, and do routine activities without pain and fracture healed uneventfully. Discussion: Acetabulum fractures are known for their complex nature and difficulty in management. We have seen this challenging case of bilateral anterior column acetabulum fracture following RTA, which has not been reported earlier and managed with open reduction and internal fixation with excellent results. Conclusion: This is among the few reported cases of bilateral anterior column acetabulum fracture due to high-velocity injury following RTA. The pattern of injury clarifies the complexity of acetabular fractures and challenges associated with treating these injuries. Such injuries will be more common in future due to increasing incidence of high-velocity trauma.

Fruit piercing moths , Eudocima sp. (Noctuidae) are common pests of ripening fruit in tropical and subtropical Southeast Asia, Australia, and the western Pacific islands. Surveys were conducted in Maharashtra revealed that three abundant larval parasitoids viz., a tachinid fly, Goniophthalmus hali , eulophid wasps, Euplectrus maternus and Tetrastichus sp. were contributing up to 36.65, 41.46 and 36.58 % larval mortality, respectively. The host specificity of parasitoids was studied in the laboratory by exposing them to larvae of Eudocima sp. However, Goniophthalmus hali showed parasitization on other species of Eudocima , whereas E. maternus is found to be host specific on E. materna species. In laboratory investigation, 72 to 89% parasitization of Trichogramma chilonis on the eggs of E. materna was also recorded.

Chikungunyna virus is expanding globally and continue to cause major public health threat to Indian populations. Vaccine efforts are underway, and it is hoped that these will eventually progress to human evaluation. However, currently we have little understanding of the phenotypes and functions of the human T cells in chikungunya patients, a knowledge that is essential for improving vaccine design/testing and evaluation efforts. Here, we provide a detailed analysis of the CD8 T cell responses in chikungunya patients from India. We found that CD38+ HLADR+ CD8 T cell subset expanded dramatically in chikungunya febrile patients with frequencies averaging about 20% of the total CD8 T cells, and reaching as high as 50% of the CD8 T cells in some patients. The frequencies of these activated CD8 T cells were substantially low and barely above background levels in afebrile patients reporting to the clinic with persistent arthralgia/arthritis that was lasting for more than 30 days. These massively expanding CD8 T cells observed in the acute febrile patients were highly proliferating (KI67 ), robustly expressing markers indicative strong Th1 differentiation (T-bet), cytotoxic functions (Perforin) and inflammatory/synovial tissue homing characteristics (CX3CR1 and CXCR4). Interestingly, antigen-stimulation mediated IFN-g producing functions of these cells was highly compromized, reminiscent of the “cytokine stunned” phenotype. Taken together, these results suggest that these highly differentiated effector CD8 T cell that were massively expanding during acute chikungunya febrile infection might be involved in protection by homing to infected tissues and eliminating infected targets rather than causing inflammation.

Individuals with dissociative identity disorder (DID) often report having no access to autobiographical experiences encoded by other identities. This research used the autobiographical Implicit Association Test (aIAT) to determine whether there was transfer of episodic self-referential memory events across amnesic identities. Nineteen DID individuals, 16 DID simulators, and 41 comparison participants (divided into amnesic and nonamnesic groups) engaged with an audio vignette of embarrassing scenarios to produce the experience of episodic self-referential events. Results showed transfer of episodic self-referential memory using the aIAT across identities that reported no conscious awareness of encoded content in DID. These aIAT results in DID patients were similar to the nonamnesic comparison group and the simulator group, and differed from the amnestic comparison group. These results are in line with previous literature showing transfer of memories, but extends this work to episodic self-referential memory. (PsycINFO Database Record (c) 2018 APA, all rights reserved).

Background As a risk-mitigation strategy to minimize paralytic polio following withdrawal of Sabin type 2 from the oral poliovirus vaccine in April 2016, a single full dose or 2 fractional doses of inactivated poliovirus vaccine (IPV) are recommended. However, limited knowledge exists on long-term persistence of immune memory following 1- or 2-dose IPV schedules. Methods We examined induction and maintenance of immune memory following single- vs 2-dose IPV schedules, either full-dose intramuscular or fractional-dose intradermal, in rhesus macaques. Humoral responses, bone marrow–homing antibody-secreting plasma cells, and blood-circulating/lymph node–homing memory B cells were examined longitudinally. Results A single dose of IPV, either full or fractional, induced binding antibodies and memory B cells in all vaccinated macaques, despite failing to induce neutralizing antibodies (NT Abs) in many of them. However, these memory B cells declined rapidly, reaching below detection in the systemic circulation by 5 months; although a low frequency of memory B cells was detectable in draining lymph nodes of some, but not all, animals. By contrast, a 2-dose vaccination schedule, either full or fractional, efficiently induced NT Abs in all animals along with bone marrow–homing plasma cells and memory B cells. These memory B cells persisted in the systemic circulation for up to 16 months, the maximum duration tested after the second dose of vaccination. Conclusions Two doses of IPV, regardless of whether fractional or full, are more effective than a single dose for inducing long-lasting memory B cells.

Background: The Indian population is facing highest dengue burden worldwide supporting an urgent need for vaccines. For vaccine introduction, evaluation and interpretation it is important to gain a critical understanding of immune memory induced by natural exposure. However, immune memory to dengue remains poorly characterized in this region. Methods: We enumerated levels of dengue specific memory B cells (MBC), neutralizing (NT) and binding antibodies in healthy adults (n = 70) from New Delhi. Results: NT-antibodies, binding antibodies and MBC were detectable in 86%, 86.56% and 81.63% of the subjects respectively. Among the neutralizing positive subjects, 58%, 27%, 5% and 10% neutralized all four, any three, any two and any one dengue serotypes respectively. The presence of the neutralizing antibodies was associated with the presence of the MBC and binding antibodies. However, a massive interindividual variation was observed in the levels of the neutralizing antibodies (range

Individuals with dissociative identity disorder (DID) often report having no access to autobiographical experiences encoded by other identities. This research used the autobiographical Implicit Association Test (aIAT) to determine whether there was transfer of episodic self-referential memory events across amnesic identities. Nineteen DID, 16 DID simulators, and 41 comparison participants (divided into amnesic and nonamnesic groups) engaged with an audio vignette of embarrassing scenarios to produce the experience of episodic self-referential events. Results showed transfer of episodic self-referential memory using the aIAT across identities that reported no conscious awareness of encoded content in DID. These aIAT results in DID patients were similar to the nonamnesic comparison group and the simulator group, and differed from the amnestic comparison group. These results are in line with previous literature showing transfer of memories, but extends this work to episodic self-referential memory

Broadly neutralizing antibodies (bNAbs) have demonstrated protective effects against HIV-1 in primate studies and recent human clinical trials. Elite neutralizers are potential candidates for isolation of HIV-1 bNAbs. The coexistence of bNAbs such as BG18 with neutralization-susceptible autologous viruses in an HIV-1-infected adult elite controller has been suggested to control viremia. Disease progression is faster in HIV-1-infected children than in adults. Plasma bNAbs with multiple epitope specificities are developed in HIV-1 chronically infected children with more potency and breadth than in adults. Therefore, we evaluated the specificity of plasma neutralizing antibodies of an antiretroviral-naive HIV-1 clade C chronically infected pediatric elite neutralizer, AIIMS_330. The plasma antibodies showed broad and potent HIV-1 neutralizing activity with >87% (29/33) breadth, a median inhibitory dilution (ID(50)) value of 1,246, and presence of N160 and N332 supersite-dependent HIV-1 bNAbs. The sorting of BG505.SOSIP.664.C2 T332N gp140 HIV-1 antigen-specific single B cells of AIIMS_330 resulted in the isolation of an HIV-1 N332 supersite-dependent bNAb, AIIMS-P01. The AIIMS-P01 neutralized 67% of HIV-1 cross-clade viruses, exhibited substantial indels despite limited somatic hypermutations, interacted with native-like HIV-1 trimer as observed in negative stain electron microscopy, and demonstrated high binding affinity. In addition, AIIMS-P01 neutralized the coexisting and evolving autologous viruses, suggesting the coexistence of vulnerable autologous viruses and HIV-1 bNAbs in the AIIMS_330 pediatric elite neutralizer. Such pediatric elite neutralizers can serve as potential candidates for isolation of novel HIV-1 pediatric bNAbs and for understanding the coevolution of virus and host immune response. IMPORTANCE More than 50% of the HIV-1 infections globally are caused by clade C viruses. To date, there is no effective vaccine to prevent HIV-1 infection. Based on the structural information of the currently available HIV-1 bNAbs, attempts are under way to design immunogens that can elicit correlates of protection upon vaccination. Here, we report the isolation and characterization of an HIV-1 N332 supersite-dependent bNAb, AIIMS-P01, from a clade C chronically infected pediatric elite neutralizer. The N332 supersite is an important epitope and is one of the current HIV-1 vaccine targets. AIIMS-P01 potently neutralized the contemporaneous and autologous evolving viruses and exhibited substantial indels despite low somatic hypermutations. Taken together with the information on infant bNAbs, further isolation and characterization of bNAbs contributing to the plasma breadth in HIV-1 chronically infected children may help provide a better understanding of their role in controlling HIV-1 infection.