28 results on '"Vasanthapuram, Ravi"'
Search Results
2. Reduced T cell immunity in unmedicated, comorbidity-free obsessive-compulsive disorder: An immunophenotyping study
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Y.C. Janardhan Reddy, Vasanthapuram Ravi, Janardhanan C. Narayanaswamy, Ganesan Venkatasubramanian, Manjula Subbanna, Dania Jose, Monojit Debnath, Venkataram Shivakumar, and Manjunath Venkataswamy
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Obsessive-Compulsive Disorder ,T cell ,chemical and pharmacologic phenomena ,T-Lymphocytes, Regulatory ,Immunophenotyping ,03 medical and health sciences ,0302 clinical medicine ,Immune system ,Humans ,Medicine ,Cytotoxic T cell ,IL-2 receptor ,Biological Psychiatry ,Cluster of differentiation ,business.industry ,CD28 ,Flow Cytometry ,030227 psychiatry ,Psychiatry and Mental health ,medicine.anatomical_structure ,Pharmaceutical Preparations ,Immunology ,business ,030217 neurology & neurosurgery ,CD8 - Abstract
Background Immune system aberrations have been postulated to play a role in the pathophysiology of Obsessive-compulsive disorder (OCD). This study was aimed to examine the profile of immune cell subsets in peripheral blood of un-medicated OCD patients. Method Thirteen drug-naive/free OCD patients and twenty-six age & sex matched healthy controls were recruited. Immunophenotyping was carried out by staining the whole blood specimens with fluorescent monoclonal antibodies against the cell surface markers such as CD45, CD3, CD16, CD56, CD8, CD4, CD28, CD25 and CD127, followed by data acquisition on BD FACSVerse™ flow cytometer. The proportions of CD4 and CD8 T cells; T regulatory (Tregs), Natural Killer (NK) cells and NK-T cells were compared between patients with OCD and healthy control subjects. Results Significantly reduced percentage of T regulatory (Treg) cells was observed in individuals with OCD compared to healthy control subjects [1.0 ± 0.7 vs. 1.9 ± 1.4; p = 0.03, r = 0.33]. Conclusion Treg cells play a crucial role in regulating the immune response, especially by suppressing the functional activities of T cells. In this study, decreased population of Treg cells essentially indicates a dysregulated T cell and/or T cell mediated immune activation in drug-naive OCD patients. This preliminary observation might form the basis of further studies examining the immuno-inflammatory/autoimmune origin of OCD.
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- 2021
3. Th17 and MAIT cell mediated inflammation in antipsychotic free schizophrenia patients
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Ruthu Nagaraju, Monojit Debnath, Chakrakodi N. Varun, Raju Ravikumar, Shivarama Varambally, Manjunatha M. Venkataswamy, Ganesan Venkatasubramanian, and Vasanthapuram Ravi
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Adult ,Male ,Adolescent ,medicine.medical_treatment ,Lymphocyte ,Population ,Central nervous system ,Inflammation ,behavioral disciplines and activities ,Peripheral blood mononuclear cell ,Mucosal-Associated Invariant T Cells ,Pathogenesis ,Young Adult ,03 medical and health sciences ,0302 clinical medicine ,Immune system ,mental disorders ,medicine ,Humans ,Antipsychotic ,education ,Biological Psychiatry ,Psychiatric Status Rating Scales ,Immunity, Cellular ,education.field_of_study ,business.industry ,Middle Aged ,030227 psychiatry ,Psychiatry and Mental health ,medicine.anatomical_structure ,Immunology ,Schizophrenia ,Th17 Cells ,Female ,medicine.symptom ,business ,030217 neurology & neurosurgery ,Antipsychotic Agents - Abstract
The immune hypothesis of schizophrenia has gained significant popularity in recent years in schizophrenia research. Evidence suggests that the peripheral immune system communicates with central nervous system and the effect propagates through microglial and lymphocyte crosstalk, especially during neuro-inflammation. Although, there is previous literature indicating changes in lymphocyte population in schizophrenia, detailed studies with respect to T and B cells are scarce. Mucosal associated invariant T (MAIT) cells are functionally associated with the gut microbiome. The gut microbiome has been implicated in the pathogenesis of schizophrenia. However, there is no information on the frequency of MAIT cells in schizophrenia. Hence, we investigated changes in proportions of T cells, B cells and MAIT cells in peripheral blood mononuclear cells derived from antipsychotic-free patients with schizophrenia in comparison to healthy controls. In line with earlier reports, we noted perturbations in Th17 cells. This study for the first time reports changes in frequencies of MAIT cells in a homogenous population of antipsychotic-free patients with schizophrenia. These changes, though not common across all patients nevertheless point to the fact that inflammation is prevalent in a significant subset of schizophrenia cases.
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- 2019
4. Plasma cytokine abnormalities in drug-naïve, comorbidity-free obsessive–compulsive disorder
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Janardhan Reddy Yc, Vasanthapuram Ravi, Ganesan Venkatasubramanian, Anish V. Cherian, Sunil V. Kalmady, and Naren P. Rao
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Adult ,Male ,Obsessive-Compulsive Disorder ,Hamilton Anxiety Rating Scale ,medicine.medical_treatment ,Anxiety ,Severity of Illness Index ,behavioral disciplines and activities ,Pathogenesis ,Interferon-gamma ,Yale–Brown Obsessive Compulsive Scale ,mental disorders ,medicine ,Humans ,Biological Psychiatry ,medicine.diagnostic_test ,Interleukin-6 ,Tumor Necrosis Factor-alpha ,Interleukin ,medicine.disease ,Comorbidity ,Interleukin-10 ,Psychiatry and Mental health ,Drug-naïve ,Cytokine ,Case-Control Studies ,Immunology ,Clinical Global Impression ,Cytokines ,Interleukin-2 ,Female ,Interleukin-4 ,Psychology ,medicine.drug - Abstract
Growing evidence in the last decade suggest significant role of immune alterations in the pathogenesis of obsessive–compulsive disorder (OCD). Cytokines, mediators of inflammation, alter the neurotransmitter concentration and result in a hyposerotonergic and hyperglutamatergic state implicated in pathogenesis of OCD. However, only few studies have examined cytokine abnormalities in OCD with inconsistent results possibly due to confounding effects of medications and comorbid anxiety–depression. We examined 20 comorbidity free, drug free OCD patients and 20 age and sex matched healthy controls. Clinical severity was assessed using Yale Brown Obsessive Compulsive Scale, Hamilton anxiety rating scale, Hamilton depression rating scale and Clinical Global Impression. Levels of different cytokines, Interleukin (IL)-2, IL-4, IL-6, IL-10, Tumor necrosis factor (TNF)-α and Interferon (IFN)-γ were assessed using Cytometric Bead Array. OCD patients had significantly greater plasma levels of IL-2, IL-4, IL-6, IL-10 and TNF-α levels than controls but not IFN-γ. Reanalysis of data with only drug naive patients (excluding 4 drug free patients) did not alter the results. Presence of these abnormalities in drug-naive patients suggests the possible role of cytokines in the pathogenesis of OCD. Study findings have potential clinical utility in development of novel therapeutic options targeting cytokine aberrations in OCD.
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- 2015
5. Single cell immune profiling of dengue virus patients reveals intact immune responses to Zika virus with enrichment of innate immune signatures
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Jayasree Sivadasan, Monique M. Richards, Megan E. Cahill, Kevin R. Moon, Brent C. Vander Wyk, Steven H. Kleinstein, Yujiao Zhao, Mahesh M. Kumar, Bram Gerritsen, Xiaomei Wang, Erol Fikrig, David van Dijk, Priti Kumar, Matthew Amodio, Anna Malawista, Anita Desai, Smita Krishnaswamy, Vasanthapuram Ravi, Ruth R. Montgomery, and Manjunatha M. Venkataswamy
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RNA viruses ,Male ,0301 basic medicine ,Viral Diseases ,Physiology ,RC955-962 ,Dengue virus ,Pathology and Laboratory Medicine ,medicine.disease_cause ,Dengue Fever ,Zika virus ,Dengue fever ,Dengue ,White Blood Cells ,0302 clinical medicine ,Animal Cells ,Immune Physiology ,Arctic medicine. Tropical medicine ,Medicine and Health Sciences ,Cytotoxic T cell ,Immune Response ,Pathogen ,Innate Immune System ,Immunity, Cellular ,T Cells ,Zika Virus Infection ,Middle Aged ,Flow Cytometry ,3. Good health ,Infectious Diseases ,Medical Microbiology ,Viral Pathogens ,Viruses ,Cytokines ,Female ,Pathogens ,Cellular Types ,Public aspects of medicine ,RA1-1270 ,Research Article ,Neglected Tropical Diseases ,Adult ,Adolescent ,Immune Cells ,Immunology ,030231 tropical medicine ,Cytotoxic T cells ,Biology ,Microbiology ,Young Adult ,03 medical and health sciences ,Immune system ,Immunity ,medicine ,Humans ,Microbial Pathogens ,Blood Cells ,Innate immune system ,Biology and life sciences ,Flaviviruses ,Organisms ,Public Health, Environmental and Occupational Health ,Zika Virus ,Cell Biology ,Dengue Virus ,Molecular Development ,Tropical Diseases ,biology.organism_classification ,medicine.disease ,Virology ,Immunity, Innate ,High-Throughput Screening Assays ,030104 developmental biology ,Immune System ,Developmental Biology - Abstract
The genus Flavivirus contains many mosquito-borne human pathogens of global epidemiological importance such as dengue virus, West Nile virus, and Zika virus, which has recently emerged at epidemic levels. Infections with these viruses result in divergent clinical outcomes ranging from asymptomatic to fatal. Myriad factors influence infection severity including exposure, immune status and pathogen/host genetics. Furthermore, pre-existing infection may skew immune pathways or divert immune resources. We profiled immune cells from dengue virus-infected individuals by multiparameter mass cytometry (CyTOF) to define functional status. Elevations in IFNβ were noted in acute patients across the majority of cell types and were statistically elevated in 31 of 36 cell subsets. We quantified response to in vitro (re)infection with dengue or Zika viruses and detected a striking pattern of upregulation of responses to Zika infection by innate cell types which was not noted in response to dengue virus. Significance was discovered by statistical analysis as well as a neural network-based clustering approach which identified unusual cell subsets overlooked by conventional manual gating. Of public health importance, patient cells showed significant enrichment of innate cell responses to Zika virus indicating an intact and robust anti-Zika response despite the concurrent dengue infection., Author summary Mosquitoes carry many globally important human pathogens including a family of related viruses: dengue virus, West Nile virus, Yellow Fever virus, and recently of critical significance, Zika virus. The Zika virus epidemic emerged very rapidly in the susceptible South American population and in many cases immune responses were unable to control the infection. Immune history is a key element of susceptibility or resistance to severe disease. We examined whether pre-existing infection would skew or divert immune resources and might play a role in the severity of Zika infection in the Americas. Using samples from dengue patients and healthy controls from India, we tested functional responses to Zika virus in the context of pre-existing dengue infection. We quantified frequency and functional status of 36 individual cell subsets in depth using advanced profiling techniques and a novel deep learning algorithm. We showed an intact response to new infection with Zika virus which was enriched for early innate immune pathways and robust even during existing dengue infection. Thus, our study suggests that concurrent dengue infection would not be expected to impair immune responses to new infection with Zika virus.
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- 2020
6. Immune aberrations in children with Autism Spectrum Disorder: a case-control study from a tertiary care neuropsychiatric hospital in India
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Satish Chandra Girimaji, Therese van Amelsvoort, Vasanthapuram Ravi, Salah Basheer, Shoba Srinath, Manjunatha M. Venkataswamy, Rita Christopher, Psychiatrie & Neuropsychologie, RS: MHeNs - R2 - Mental Health, and MUMC+: MA Med Staf Spec Psychiatrie (9)
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0301 basic medicine ,Male ,Myeloid ,INTELLECTUAL DISABILITY ,Autism Spectrum Disorder ,Endocrinology, Diabetes and Metabolism ,medicine.medical_treatment ,Monocytes ,ACTIVATION ,0302 clinical medicine ,Endocrinology ,Immunophenotyping ,Medicine ,Myeloid Cells ,TH17 ,Prospective Studies ,Child ,biology ,ABNORMALITIES ,Interleukin-17 ,Flow Cytometry ,Psychiatry and Mental health ,IL-17 ,medicine.anatomical_structure ,Cytokine ,Autism spectrum disorder ,Child, Preschool ,Cytokines ,Female ,Interleukin 17 ,India ,Myeloid dendritic cells ,PERIPHERAL-BLOOD ,03 medical and health sciences ,Immune system ,mental disorders ,Humans ,Interleukin 6 ,Biological Psychiatry ,Inflammation ,IL-6 ,Endocrine and Autonomic Systems ,business.industry ,Interleukin-6 ,Tertiary Healthcare ,Case-control study ,Dendrites ,medicine.disease ,MICE ,030104 developmental biology ,Cross-Sectional Studies ,Immune dysfunction ,Case-Control Studies ,Immunology ,biology.protein ,T-CELLS ,ASTHMA ,Th17 Cells ,business ,030217 neurology & neurosurgery ,SYSTEM - Abstract
Multiple studies have identified the presence of peripheral immune aberrations in subjects with Autism Spectrum Disorder (ASD). However, comprehensive assessment of these peripheral immune aberrations, in the cellular and systemic compartments, in a single group of subjects with ASD is lacking. We assessed proportions of various subsets of immune cells in peripheral blood (T helper cells, T regulatory cells, B cells, monocytes, Natural Killer cells, dendritic cells) by multi-parametric flow cytometry in 50 children with ASD and compared it with thirty healthy controls matched for age, gender, socio-economic status and body mass index. There were no significant differences noted in the proportion of T regulatory cells, B cells, monocytes and Natural Killer cells, between ASD subjects and controls. On the contrary, the proportion of activated Th17 and myeloid dendritic cells were significantly higher in children with ASD. Based on these findings, group comparison of serum levels of Th17 cytokines (interleukin-6, interleukin-17A) was performed. Elevated serum levels of interleukin-6 and interleukin-17A in children with ASD corroborated our immunophenotyping findings. We did not find any significant differences among the pro-inflammatory (interleukin-1 beta), Th1 (interferon-gamma) and Th2 (interleukin-4) cytokines. This is the first evidence with concurrent findings from immunophenotyping and cytokine data demonstrating activation of the Th17 pathway in subjects with ASD. This finding assumes significance in the light of recent maternal immune activation mouse model study that has highlighted the role of Th17 pathway in the pathophysiology of ASD. Future longitudinal studies are needed to clarify the role of this dysregulated immune pathway in the development of ASD.
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- 2018
7. Plasma cytokines in minimally treated schizophrenia
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Sunil V. Kalmady, Venkataram Shivakumar, Vasanthapuram Ravi, Bangalore N. Gangadhar, Dania Jose, Ganesan Venkatasubramanian, and Matcheri S. Keshavan
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0301 basic medicine ,Adult ,Male ,Pathogenesis ,03 medical and health sciences ,0302 clinical medicine ,medicine ,Humans ,Interferon gamma ,Interleukin 6 ,Biological Psychiatry ,biology ,business.industry ,Confounding ,Interleukin ,medicine.disease ,Psychiatry and Mental health ,030104 developmental biology ,Schizophrenia ,Immunology ,biology.protein ,Cytokines ,Tumor necrosis factor alpha ,Female ,Interleukin 17 ,business ,030217 neurology & neurosurgery ,Biomarkers ,medicine.drug - Abstract
In schizophrenia, plasma cytokines abnormalities offer vital support for immunopathogenetic basis. However, most of the previous studies on plasma cytokines are confounded by examination of antipsychotic-treated schizophrenia patients. In this study, we examined a large sample of antipsychotic-naive/free schizophrenia patients (N = 75) in comparison with healthy controls (N = 102). Plasma cytokines (Interleukins ([IL] 2, 4, 6, 10, 17), Tumor necrosis factor [TNF] and Interferon gamma [IFN-g]) were assessed using cytometric bead array assay. Schizophrenia patients showed significantly greater levels of IL-6 and lower levels of IL-17 as well as IFN-g in comparison to healthy controls. However, after taking censoring into account and adjusting for potential confounders (sex, age, BMI and smoking), only IL-6 was found to be elevated in patients. Cytokine profile showed differential and pathogenetically relevant correlation with clinical symptoms. Together, these observations offer further support to immunological component in schizophrenia pathogenesis.
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- 2017
8. Correlation of plasma viral loads and presence of Chikungunya IgM antibodies with cytokine/chemokine levels during acute Chikungunya virus infection
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Vasanthapuram Ravi, Vijayalakshmi Reddy, Reeta S. Mani, and Anita Desai
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Chemokine ,medicine.medical_treatment ,virus diseases ,Disease ,Biology ,medicine.disease_cause ,Virology ,Pathogenesis ,Infectious Diseases ,Real-time polymerase chain reaction ,Immune system ,Cytokine ,Immunology ,medicine ,biology.protein ,Chikungunya ,Viral load - Abstract
Chikungunya (CHIKV) is an emerging arboviral infection of public health concern in India contributing to widespread morbidity. The precise molecular events occurring early in the infection have not been well understood. Cytokines/chemokines are suspected to play a key role in its pathogenesis. Very few studies have correlated the plasma levels of cytokines/chemokines with diagnostic markers such as viral loads and presence of CHIKV IgM antibodies. Understanding these dynamics in the early phase of CHIKV infection is likely to provide an insight into the evolution of the immune response, identify biomarkers for assessing severity, and for development of newer therapeutic strategies. This study was therefore undertaken to estimate the levels of various cytokines/chemokines in plasma samples of patients infected with CHIKV and correlate to viral load and CHIKV IgM antibodies. Cytokine/chemokine levels and viral loads in plasma were measured using cytometric bead array and TaqMan real time PCR assay, respectively. The findings revealed that acute phase of CHIKV infection is characterized by predominant inflammatory responses mediated by IL-6, IL-8, IP-10, MCP-1, and MIG (P
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- 2014
9. Association of Neurotropic Viruses in HIV-Infected Individuals Who Died of Secondary Complications of Tuberculosis, Cryptococcosis, or Toxoplasmosis in South India
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Gopalan Sridharan, Jaiprasath Sachithanandham, Susarla K. Shankar, Anita Mahadevan, Asha Mary Abraham, Anita Desai, Vasanthapuram Ravi, and Rajesh Kannangai
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Microbiology (medical) ,viruses ,AIDS-Related Opportunistic Infections ,JC virus ,India ,HIV Infections ,medicine.disease_cause ,Virus ,Virology ,Prevalence ,medicine ,Humans ,Tuberculosis ,Cerebrospinal Fluid ,biology ,Progressive multifocal leukoencephalopathy ,DNA Viruses ,Brain ,virus diseases ,Cytomegalovirus ,Cryptococcosis ,biology.organism_classification ,medicine.disease ,DNA Virus Infections ,Herpes simplex virus ,Immunology ,Coinfection ,Human herpesvirus 6 ,Multiplex Polymerase Chain Reaction ,Toxoplasmosis - Abstract
The frequencies of 10 opportunistic DNA viruses were determined by multiplex real-time PCR in paired cerebrospinal fluid (CSF) and brain tissue of HIV-infected individuals. In the CSF, viruses were detectable in 45/55 cases: JC virus (JCV) in 62%, Epstein-Barr virus (EBV) in 44%, cytomegalovirus (CMV) in 25%, varicella-zoster virus (VZV) in 3.6%, herpes simplex virus 1 (HSV-1) in 1.8%, and human herpesvirus 6 (HHV-6) in 1.8% of cases. A single virus was detectable in 20 cases, 19 cases had coinfection with two viruses, and 6 cases were positive for three viruses. JCV was detectable in the CSF of 62% of cases and in 42% of brain tissues, with higher loads in progressive multifocal leukoencephalopathy (PML) ( P < 0.05).
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- 2013
10. Human T cell responses to Japanese encephalitis virus in health and disease
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M. Veera Shankar, Stefan Fernandez, Ayako Kurioka, Vishali Satishkumar, Prachi Fadnis, Lance Turtle, Manjunatha M. Venkataswamy, Mohammed Soni, Mohammed Hussain, Sajesh Chan, Savita Chib, Ashia Begum, Paul Klenerman, Vasanthapuram Ravi, Gemma Buxton, Christopher P. Conlon, Penny Lewthwaite, Anita Desai, Tom Solomon, Srinivasa Krishna, Vijaya Satchidanandam, Christian B. Willberg, Riyaz Ahmed, Tanushka Bali, Henrik N. Kløverpris, Sutee Yoksan, and Heather Isenman
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0301 basic medicine ,Adult ,CD4-Positive T-Lymphocytes ,Male ,Adolescent ,T cell ,viruses ,030231 tropical medicine ,Immunology ,Dengue virus ,Biology ,CD8-Positive T-Lymphocytes ,Cross Reactions ,Viral Nonstructural Proteins ,medicine.disease_cause ,Virus ,Article ,Zika virus ,03 medical and health sciences ,Interferon-gamma ,0302 clinical medicine ,medicine ,Immunology and Allergy ,Humans ,Child ,Encephalitis, Japanese ,Research Articles ,Encephalitis Virus, Japanese ,Microbiology & Cell Biology ,virus diseases ,Japanese encephalitis ,Dengue Virus ,medicine.disease ,biology.organism_classification ,Virology ,3. Good health ,Flavivirus ,030104 developmental biology ,medicine.anatomical_structure ,Female ,Immunologic Memory ,CD8 ,Encephalitis - Abstract
Healthy donors exposed to Japanese encephalitis (JE) virus show a CD8+ T cell response that cross reacts with other flaviviruses. Patients that recovered from JE show a CD4+ T cell response that targets structural proteins of JE virus., Japanese encephalitis (JE) virus (JEV) is an important cause of encephalitis in children of South and Southeast Asia. However, the majority of individuals exposed to JEV only develop mild symptoms associated with long-lasting adaptive immunity. The related flavivirus dengue virus (DENV) cocirculates in many JEV-endemic areas, and clinical data suggest cross-protection between DENV and JEV. To address the role of T cell responses in protection against JEV, we conducted the first full-breadth analysis of the human memory T cell response using a synthetic peptide library. Ex vivo interferon-γ (IFN-γ) responses to JEV in healthy JEV-exposed donors were mostly CD8+ and targeted nonstructural (NS) proteins, whereas IFN-γ responses in recovered JE patients were mostly CD4+ and targeted structural proteins and the secreted protein NS1. Among patients, a high quality, polyfunctional CD4+ T cell response was associated with complete recovery from JE. T cell responses from healthy donors showed a high degree of cross-reactivity to DENV that was less apparent in recovered JE patients despite equal exposure. These data reveal divergent functional CD4+ and CD8+ T cell responses linked to different clinical outcomes of JEV infection, associated with distinct targeting and broad flavivirus cross-reactivity including epitopes from DENV, West Nile, and Zika virus.
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- 2016
11. Gene Expression Analysis from Human Immunodeficiency Virus Type 1 Subtype C Promoter and Construction of Bicistronic Reporter Vectors
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Narayana Jayasuryan, Susarla K. Shankar, Nagadenahalli B. Siddappa, Venkatesh Prasanna Kashi, Anita Desai, Kadappa Shivappa Satish, Anangi Balasiddaiah, Anita Mahadevan, Mohanram Venkatramanan, Vasanthapuram Ravi, and Udaykumar Ranga
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Adult ,Gene Expression Regulation, Viral ,Male ,viruses ,Genetic Vectors ,Green Fluorescent Proteins ,Immunology ,HIV Core Protein p24 ,India ,Biology ,Lymphocyte Activation ,Cell Line ,Transactivation ,Genes, Reporter ,Virology ,Viral structural protein ,Humans ,Promoter Regions, Genetic ,Enhancer ,Gene ,Phylogeny ,HIV Long Terminal Repeat ,Reporter gene ,Genetic Variation ,Middle Aged ,Alkaline Phosphatase ,Molecular biology ,Long terminal repeat ,DNA binding site ,Infectious Diseases ,Genes, tat ,HIV-1 ,Female ,Expression cassette - Abstract
We report the cloning and sequence analysis of the long terminal repeat (LTR) of several primary HIV-1 subtype C strains of India. Phylogenetically, all the LTRs and the paired env sequences clustered with subtype C reference strains. The LTRs demonstrated extensive polymorphism in the transcription factor binding sites (TFBS) within the enhancer and the modulator regions. We generated reporter vectors under the control of a select subset of the subtype C LTRs. The reporter vectors are distinguished by the simultaneous expression of two independent reporter genes, secreted alkaline phosphatase (SEAP) and enhanced green fluorescence protein (EGFP), in response to Tat. Expression of EGFP was facilitated by engineering an internal ribosome entry site (IRES) into the expression cassette. Although subtype C strains cause a large majority of the global infections, and important differences in the transcription factor binding sites have been identified in the subtype C promoter, few reporter vectors containing subtype C-LTR have been described. We analyzed gene expression from the C-LTR reporter vectors in different cell lines under diverse experimental conditions and compared it to the B-LTR reporter vector. The reporter vectors were responsive to Tat derived from diverse viral subtypes. Furthermore, a positive correlation was observed between the expression of the reporter genes and the viral structural protein p24 when the cells were infected with viral molecular clones. The LTR reporters we developed could be of significant use in the study of viral transactivation, in the evaluation of biological properties of viral subtypes, and in the screening for antiviral inhibitors.
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- 2007
12. Use of Neutralizing Murine Monoclonal Antibodies to Rabies Glycoprotein in Passive Immunotherapy Against Rabies
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Kader Muhamuda, Vasanthapuram Ravi, and Shampur Narayan Madhusudana
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medicine.drug_class ,Guinea Pigs ,Immunology ,Antibodies, Viral ,Monoclonal antibody ,Virus ,Subclass ,Mice ,Viral Proteins ,medicine ,Animals ,General Pharmacology, Toxicology and Pharmaceutics ,Glycoproteins ,Duck embryo vaccine ,chemistry.chemical_classification ,Mice, Inbred BALB C ,business.industry ,Immunization, Passive ,Antibodies, Monoclonal ,medicine.disease ,Virology ,Titer ,Treatment Outcome ,Rabies Vaccines ,chemistry ,Immunization ,Rabies virus ,Rabies ,business ,Glycoprotein - Abstract
Passive immunization is an important parameter of post exposure rabies prophylaxis. Two types of rabies immunoglobulin (RIGs) are currently available for Passive immunization against rabies i.e., human rabies immunoglobulin (HRIG) and equine rabies immunoglobulin (ERIG). The former is very expensive and not easily available and the latter causes side effects because of which its utility is limited. In the present study we have produced murine monoclonal antibodies (Mabs) to rabies glycoprotein (G) and studied their utility in passive immunization against rabies using animal models. Their efficacy was compared to commercially available ERIG both in terms of neutralizing titer and effective protein concentration. The neutralizing titers of these Mabs ranged from 1650-75,000 IU/mL by RFFIT. They belonged to the IgG 2 a subclass. The Mabs were able to protect 70-100% of mice and guinea pigs inoculated with rabies viruses, depending on the strain of the virus. These Mabs were found to be 2,000 times more potent than commercial ERIG in terms of effective protein concentration and neutralizing titer. Further studies are required to study their utility in humans exposed to rabies.
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- 2007
13. Neuropsychological deficits in human immunodeficiency virus type 1 clade C–seropositive adults from South India
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Parthasarthy Satishchandra, Mahendra Kumar, K.S. Satish, D.K. Subbakrishna, B. S. Rao, Vasanthapuram Ravi, Raymond L. Ownby, Drenna Waldrop-Valverde, Anupa Kamat, Jayashree Das Gupta, Kumarpillai Gopukumar, Anita Desai, Frances L. Wilkie, and Ronald J. Ellis
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Adult ,Male ,Pediatrics ,medicine.medical_specialty ,AIDS Dementia Complex ,India ,Neuropsychological Tests ,Cohort Studies ,Cellular and Molecular Neuroscience ,Virology ,HIV Seropositivity ,Prevalence ,medicine ,Humans ,Cognitive skill ,Clade ,medicine.diagnostic_test ,Neuropsychology ,Cognition ,Neuropsychological test ,Viral Load ,Memory, Short-Term ,Neurology ,Immunology ,HIV-1 ,Female ,Neurology (clinical) ,Viral disease ,Cognition Disorders ,Psychology ,Viral load ,Cohort study - Abstract
Most studies of cognitive functioning in human immunodeficiency virus type 1 (HIV-1)-seropositive (HIV-1+) subjects have been done in the United States and Europe, where clade B infections predominate. However, in other parts of the world such as South India, where clade C HIV is most common, the prevalence of HIV-1 is increasing. Standardized neuropsychological tests were used to assess cognitive functioning in a sample of 119 adults infected with clade C HIV-1 who were not on antiretroviral medications. The subjects did not have neurological or psychiatric illness and were functioning adequately. Neuropsychological test performance was compared with gender-, age-, and education-matched normative data derived from a sample of 540 healthy volunteers and a matched cohort of 126 healthy, HIV-1-seronegative individuals. Among the seropositive subjects, 60.5% had mild to moderate cognitive deficits characterized by deficits in the domains of fluency, working memory, and learning and memory. None of the subjects had severe cognitive deficits. The HIV-1+ sample was classified into groups according to the level of immune suppression as defined by CD4 count (200, 201-499, and500 cells/mm3) and viral load (5000, 5001-30,000, 30,001-99,999, 100,000-1,000,000, and1,000,001 copies). Although the most immunosuppressed group (CD4 count200 cells/mm3 or viral load1,000,001 copies) was small, their rate of impairment in visual working memory was greater when compared to groups with better immune functioning. Mild to moderate cognitive deficits can be identified on standardized neuropsychological tests in clade C-infected HIV-1+ adults who do not have any clinically identifiable functional impairment. The prevalence of cognitive deficits is similar to that reported in antiretroviral treatment-naïve individuals infected with clade B virus in the western world.
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- 2007
14. Quality of life in HIV subtype C infection among asymptomatic subjects and its association with CD4 counts and viral loads – a study from South India
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Charu Gandhi, Raymond L. Ownby, Anita Desai, Mahendra Kumar, Vasanthapuram Ravi, D.K. Subbakrishna, Parthasarthy Satishchandra, Anupa Kamat, and Prabha S. Chandra
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Adult ,Male ,medicine.medical_specialty ,India ,HIV Infections ,Asymptomatic ,Quality of life ,Internal medicine ,Health Status Indicators ,Humans ,Medicine ,Association (psychology) ,business.industry ,Public health ,Disease progression ,Public Health, Environmental and Occupational Health ,Viral Load ,Hiv subtype ,humanities ,CD4 Lymphocyte Count ,Immunology ,Disease Progression ,Quality of Life ,Female ,medicine.symptom ,business ,Viral load ,Biomarkers ,Cohort study - Abstract
To study the association between quality of life (QOL) domains and biological markers of disease progression of HIV infection, i.e. viral load (VL) and CD4 counts among asymptomatic subjects with HIV subtype C infection in South India. Quality of life was measured using the locally validated version of the WHOQOL HIV-BREF. The subjects were neurologically asymptomatic, non psychiatrically ill HIV infected men and women participating in a cohort study. The results indicated mixed findings, with some QOL dimensions being associated with high VLs and low CD4 counts while several others did not show any associations. Significant associations were seen between low CD4 counts and the psychological and social relationships domain, with lower mean scores in these domains being reported by subjects having CD4 counts
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- 2006
15. Comparison of Safety and Immunogenicity of Purified Chick Embryo Cell Rabies Vaccine (PCECV) and Purified Vero Cell Rabies Vaccine (PVRV) Using the Thai Red Cross Intradermal Regimen at a Dose of 0.1 ML
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Anand Giri, Doddabele Hanumanthaiah Ashwath Narayana, Thitamaranahalli V. Sanjay, Kader Muhamuda, Vasanthapuram Ravi, M.K. Sudarshan, Hoshang B. Vakil, B J Mahendra, Cladius Malerczyk, and Shampur Narayan Madhusudana
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Adult ,Male ,Adolescent ,Immunology ,Chick Embryo ,Antibodies, Viral ,World Health Organization ,medicine.disease_cause ,Rabies vaccine ,Chlorocebus aethiops ,medicine ,Animals ,Humans ,General Pharmacology, Toxicology and Pharmaceutics ,Child ,Vero Cells ,business.industry ,Immunogenicity ,Rabies virus ,medicine.disease ,Virology ,Vaccination ,Titer ,Regimen ,Rabies Vaccines ,Tolerability ,Child, Preschool ,Female ,Rabies ,business ,medicine.drug - Abstract
Intradermal (ID) vaccination with modern cell culture rabies vaccines is a means to significantly reduce the cost of post-exposure prophylaxis as compared to intramuscular vaccination. In this study we evaluated the efficacy, immunogenicity and tolerability of PCECV and PVRV administered ID in doses of 0.1 mL per site according to the 2-site Thai Red Cross (TRC) regimen. Patients with WHO category III exposure to suspect or laboratory proven rabid animals were administered either PCECV (n = 58) or PVRV (n = 52) ID at a dose of 0.1 mL per site at two sites on days 0, 3 and 7 and at one site on days 30 and 90. Serum samples were withdrawn on days 0, 14, 30, 90 and 180 and rabies virus neutralizing antibody (RVNA) titers were determined by rapid fluorescent focus inhibition test (RFFIT). Patients who were exposed to laboratory confirmed rabid animals were followed up for one year after exposure. All 110 patients developed RVNA titers above 0.5 IU/mL by day 14. Adequate titers >0.5 IU/mL were maintained up to day 180. Both vaccines induced equivalent RVNA titers at all time points and were well tolerated. Five subjects who were bitten by laboratory confirmed rabid dogs were alive and healthy one year after exposure. As demonstrated, PCECV and PVRV are both immunogenic, efficacious and well tolerated when administered in the TRC post-exposure prophylaxis regimen in ID doses of 0.1 mL as recommended by WHO guidelines. The use of PCECV in this regimen may prove more economical in developing countries like India.
- Published
- 2006
16. Detection of Antibody toMycobacterium tuberculosisProtein Antigens in the Cerebrospinal Fluid of Patients with Tuberculous Meningitis
- Author
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A. Chandramuki, Philip Alcabes, Konstantin P. Lyashchenko, Maria Laura Gennaro, S. K. Shankar, Haradara Bahubali Veena Kumari, PierNatale Brusasca, Ganga V. Kanaujia, Khanna N, Vasanthapuram Ravi, Parthasarathy Satishchandra, and Mandavalli Gourie-Devi
- Subjects
Pathology ,medicine.medical_specialty ,Tuberculosis ,India ,Enzyme-Linked Immunosorbent Assay ,HIV Infections ,Antibodies, Viral ,urologic and male genital diseases ,Tuberculous meningitis ,Mycobacterium tuberculosis ,Cerebrospinal fluid ,Antigen ,medicine ,Humans ,Immunology and Allergy ,Retrospective Studies ,Antigens, Bacterial ,biology ,business.industry ,HIV ,biology.organism_classification ,medicine.disease ,Antibodies, Bacterial ,Infectious Diseases ,Tuberculosis, Meningeal ,Humoral immunity ,Immunology ,biology.protein ,Antibody ,business ,Meningitis - Abstract
Antibodies against Mycobacterium tuberculosis antigens were detected by enzyme-linked immunosorbent assay in cerebrospinal fluid (CSF) samples obtained from 442 patients with tuberculous meningitis (TBM) and 102 control patients. Antibodies were found in the CSF of 87% of patients with clinical (culture-negative) TBM, 72% of patients with culture-positive TBM, and 65% of patients with autopsy-proven TBM. That anti-M. tuberculosis antibodies were detected in the CSF of patients with clinically diagnosed cases more frequently than in patients with culture-positive cases suggests that the detection of antibodies in CSF tends to decrease as bacillary load increases. Of the patients with clinical TBM who were coinfected with human immunodeficiency virus (HIV), 70% exhibited anti-M. tuberculosis antibody in CSF, which suggests that antibody responses in this group were substantially weaker than those in HIV-negative patients with clinical TBM. Some groups showed a stronger response to certain antigens, which suggests that antigen recognition patterns may be specific for the stage of disease.
- Published
- 2002
17. Relationship between Interleukin-6 gene polymorphism and hippocampal volume in antipsychotic-naïve schizophrenia: evidence for differential susceptibility?
- Author
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Aditi Subramaniam, Arindam Maitra, Venkataram Shivakumar, S. Gautham, Dania Jose, Sunil V. Kalmady, Bangalore N. Gangadhar, Ganesan Venkatasubramanian, and Vasanthapuram Ravi
- Subjects
Male ,Pathology ,Hippocampus ,lcsh:Medicine ,Social Sciences ,Hippocampal formation ,Pathogenesis ,0302 clinical medicine ,Medicine and Health Sciences ,Psychology ,Gray Matter ,lcsh:Science ,0303 health sciences ,Multidisciplinary ,biology ,Organ Size ,3. Good health ,Schizophrenia ,Female ,Antipsychotic Agents ,Research Article ,Adult ,medicine.medical_specialty ,Epigenetics of schizophrenia ,Polymorphism, Single Nucleotide ,03 medical and health sciences ,Neuropsychology ,Mental Health and Psychiatry ,Genetic predisposition ,medicine ,Genetics ,Humans ,Interleukin 6 ,030304 developmental biology ,Evolutionary Biology ,Population Biology ,Interleukin-6 ,lcsh:R ,Case-control study ,Biology and Life Sciences ,Computational Biology ,medicine.disease ,Case-Control Studies ,Immunology ,biology.protein ,Genetic Polymorphism ,lcsh:Q ,030217 neurology & neurosurgery ,Population Genetics ,Neuroscience - Abstract
Background Various lines of evidence including epidemiological, genetic and foetal pathogenetic models suggest a compelling role for Interleukin-6 (IL-6) in the pathogenesis of schizophrenia. IL-6 mediated inflammatory response triggered by maternal infection or stress induces disruption of prenatal hippocampal development which might contribute towards psychopathology during adulthood. There is a substantial lack of knowledge on how genetic predisposition to elevated IL-6 expression effects hippocampal structure in schizophrenia patients. In this first-time study, we evaluated the relationship between functional polymorphism rs1800795 of IL-6 and hippocampal gray matter volume in antipsychotic-naïve schizophrenia patients in comparison with healthy controls. Methodology We examined antipsychotic-naïve schizophrenia patients [N = 28] in comparison with healthy controls [N = 37] group matched on age, sex and handedness. Using 3 Tesla – MRI, bilateral hippocampi were manually segmented by blinded raters with good inter-rater reliability using a valid method. Additionally, Voxel-based Morphometry (VBM) analysis was performed using hippocampal mask. The IL-6 level was measured in blood plasma using ELISA technique. SNP rs1800795 was genotyped using PCR and DNA sequencing. Psychotic symptoms were assessed using Scale for Assessment of Positive Symptoms and Scale for Assessment of Negative Symptoms. Results Schizophrenia patients had significantly deficient left and right hippocampal volumes after controlling for the potential confounding effects of age, sex and total brain volume. Plasma IL-6 levels were significantly higher in patients than controls. There was a significant diagnosis by rs1800795 genotype interaction involving both right and left hippocampal volumes. Interestingly, this effect was significant only in men but not in women. Conclusion Our first time observations suggest a significant relationship between IL-6 rs1800795 and reduced hippocampal volume in antipsychotic-naïve schizophrenia. Moreover, this relationship was antithetical in healthy controls and this effect was observed in men but not in women. Together, these observations support a “differential susceptibility” effect of rs1800795 in schizophrenia pathogenesis mediated through hippocampal volume deficit that is of possible neurodevelopmental origin.
- Published
- 2013
18. Protection of adult but not newborn mice against lethal intracerebral challenge with Japanese encephalitis virus by adoptively transferred virus-specific cytotoxic T lymphocytes: requirement for L3T4+ T cells
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Kaja Murali-Krishna, Vasanthapuram Ravi, and Ramanathapuram Manjunath
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Antigens, Differentiation, T-Lymphocyte ,Male ,Aging ,Adoptive cell transfer ,Virus-specific Cytotoxic T-lymphocytes ,viruses ,T cell ,Lymphocyte ,medicine.medical_treatment ,Biology ,Antibodies, Viral ,Immunotherapy, Adoptive ,Biochemistry ,Virus ,Mice ,Antigen ,Neutralization Tests ,T-Lymphocyte Subsets ,Virology ,medicine ,Animals ,Humans ,Cytotoxic T cell ,Encephalitis, Japanese ,Encephalitis Virus, Japanese ,Mice, Inbred BALB C ,Immunotherapy ,medicine.anatomical_structure ,Animals, Newborn ,CD4 Antigens ,Immunology ,T-Lymphocytes, Cytotoxic - Abstract
The protective ability of cytotoxic T cells (CTL) raised in vitro against Japanese encephalitis virus (JEV) was examined by adoptive transfer experiments. Adoptive transfer of anti-JEV effecters by intracerebral (i.c.) but not by intraperitoneal (i.p.) or intravenous (i.v.) routes protected adult BALB/c mice against lethal i.c. JEV challenge. In contrast to adult mice, adoptive transfer of anti-JEV effecters into newborn (4-day-old) and suckling (8-14-day-old) mice did not confer protection. However, virus-induced death was delayed in suckling mice compared to newborn mice upon adoptive transfer. The specific reasons for lack of protection in newborn mice are not clear but virus load was found to be higher in newborn mice brains compared to those of adults and virus clearance was observed only in adult mice brains but not in newborn mice brains upon adoptive transfer. Specific depletion of Lyt 2.2(+), L3T4(+) or Thy-1(+) T cell populations before adoptive transfer abrogated the protective ability of transferred effecters. However, when Lyt 2.2(+) cell-depleted and L3T4(+) cell-depleted effecters were mixed and transferred into adult mice the protective activity was retained, demonstrating that both Lyt 2.2(+) and L3T4(+) T cells are necessary to confer protection. Although the presence of L3T4(+) T cells in adoptively transferred effector populations enhanced virus-specific serum neutralizing antibodies, the presence of neutralizing antibodies alone without Lyt 2.2(+) cells was not sufficient to confer protection.
- Published
- 1996
19. Recognition of Nonstructural Protein Peptides by Cytotoxic T Lymphocytes Raised against Japanese Encephalitis Virus
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Bommireddy Ramireddy, Ramanathapuram Manjunath, Vasanthapuram Ravi, and Kaja Murali-Krishna
- Subjects
viruses ,Molecular Sequence Data ,Immunology ,chemical and pharmacologic phenomena ,In Vitro Techniques ,Viral Nonstructural Proteins ,Biology ,Microbiology ,Epitope ,Virus ,Epitopes ,Mice ,Antigen ,Virology ,medicine ,Animals ,Cytotoxic T cell ,Amino Acid Sequence ,Antigens, Viral ,Encephalitis Virus, Japanese ,Mice, Inbred BALB C ,NS3 ,Binding Sites ,H-2 Antigens ,virus diseases ,hemic and immune systems ,biochemical phenomena, metabolism, and nutrition ,Japanese encephalitis ,medicine.disease ,biology.organism_classification ,Molecular biology ,Peptide Fragments ,Flavivirus ,CTL ,Protein Binding ,T-Lymphocytes, Cytotoxic - Abstract
We have previously reported that Lyt(2+) cytotoxic T lymphocytes (CTL) can be raised against Japanese encephalitis virus (JEV) in BALB/c mice. In order to confirm the presence of H-2K(d)-restricted CTL and to examine their cross-recognition of West Wile virus (WNV), we tested the capacity of anti-JEV CTL to lyse uninfected syngeneic target cells that were pulsed with synthetic peptides. The sequence of the synthetic peptides was predicted based upon the H-2K(d) binding consensus motif. We show here that preincubation of uninfected syngeneic targets (P388D1) with JEV NS1- and NS3-derived peptides [NS1 (891-899) and NS3 (1804-1812)], but not with JEV NS5-derived peptide [NS5 (3370-3378)], partially sensitized them for lysis by polyclonal anti-JEV CTL. These results indicate the CTL recognition of NS1- and NS3-derived peptides of JEV.
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- 1995
20. Persistence of Japanese encephalitis virus in the human nervous system
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Parthasarathy Satishchandra, Anita Desai, Poornima K. Shenoy, Mandaville Gourie-Devi, Vasanthapuram Ravi, and A. Chandramuki
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Adult ,Male ,viruses ,Biology ,Antibodies, Viral ,Nervous System ,Virus ,Serology ,Flaviviridae ,Virology ,medicine ,Humans ,Child ,Encephalitis, Japanese ,Antigens, Viral ,Encephalitis Virus, Japanese ,Infant ,Middle Aged ,Japanese encephalitis ,biology.organism_classification ,medicine.disease ,Japanese B Encephalitis ,Flavivirus ,Infectious Diseases ,Immunoglobulin M ,Child, Preschool ,Immunology ,Female ,Viral disease ,Encephalitis - Abstract
Immunological and virological evidence for persistence of Japanese encephalitis virus (JEV) in the human nervous system is described in 16/323 (5%) laboratory-confirmed cases of Japanese encephalitis. In 9/16 patients, JEV specific IgM antibodies were detected in the CSF even at 50-180 days after the onset of symptoms. Similarly, in 7/16 patients, apart from IgM antibodies, viral antigen was also present in the CSF beyond the third week of illness and in one patient it could be detected even at 117 days. Infectious virus could be isolated from the CSF beyond the third week of illness in 3/16 patients. In one patient, JEV was isolated from the CSF on three consecutive occasions at 90, 110, and 117 days after onset of clinical symptoms. These findings suggest that JEV persists in the nervous system of a small proportion of patients.
- Published
- 1993
21. Evaluation of IgM antibody capture enzyme-linked immunosorbent assay kits for detection of IgM against Japanese encephalitis virus in cerebrospinal fluid samples
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Barbara W. Johnson, Vasanthapuram Ravi, Anita Desai, Jaimie S. Robinson, David Featherstone, Brandy J. Russell, and Nalini Ramamurty
- Subjects
Adult ,Male ,Adolescent ,viruses ,Enzyme-Linked Immunosorbent Assay ,Virus ,Flaviviridae ,Young Adult ,Cerebrospinal fluid ,Virology ,medicine ,Humans ,Child ,Encephalitis, Japanese ,Aged ,chemistry.chemical_classification ,Encephalitis Virus, Japanese ,biology ,Japanese encephalitis ,Middle Aged ,biology.organism_classification ,medicine.disease ,Flavivirus ,Infectious Diseases ,Enzyme ,chemistry ,Immunoglobulin M ,Child, Preschool ,Immunology ,biology.protein ,Parasitology ,Female ,Reagent Kits, Diagnostic ,Antibody ,Encephalitis - Abstract
Infection with Japanese encephalitis virus (JEV) is a major public health problem in Asia. Detection of JEV-specific IgM in serum and cerebrospinal fluid (CSF) by the IgM antibody capture enzyme-linked immunosorbent assay (MAC-ELISA) is currently the most widely used diagnostic method to detect JEV infection. Because of the possible presence of IgM cross-reactivity with other flaviviruses in serum and the high ratio of inapparent-to-apparent JEV infections, a positive result in serum only suggests a recent infection and not necessarily an encephalitic illness caused by JEV. Consequently, detection of JEV-specific IgM in CSF assumes great diagnostic relevance. We evaluated two commercial JEV MAC-ELISA kits using 60 CSF samples obtained from patients with acute encephalitis syndrome. The Panbio and XCyton kits had sensitivities of 65-80% and 95% and specificities of 90% and 97.5%, respectively. Performance information on these commercial JEV MAC-ELISA kits for CSF should assist in laboratory-based JE surveillance programs.
- Published
- 2009
22. Mycophenolic acid inhibits replication of Japanese encephalitis virus
- Author
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Shampur Narayan Madhusudana, Liba Sebastian, Vasanthapuram Ravi, and Anita Desai
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medicine.medical_specialty ,health care facilities, manpower, and services ,Virus Replication ,Antiviral Agents ,Mycophenolic acid ,Virus ,Mice ,parasitic diseases ,Drug Discovery ,medicine ,Animals ,Pharmacology (medical) ,Encephalitis, Japanese ,health care economics and organizations ,Pharmacology ,Encephalitis Virus, Japanese ,business.industry ,Public health ,social sciences ,General Medicine ,Japanese encephalitis ,Mycophenolic Acid ,medicine.disease ,Virology ,Infectious Diseases ,Oncology ,Immunology ,Sri lanka ,business ,geographic locations ,Encephalitis ,medicine.drug - Abstract
Background: Japanese encephalitis is a major public health problem in several parts of Asia, particularly India, Nepal, Sri Lanka and Myanmar (Burma). Despite its public health implications, there are no effective antiviral drugs available. Methods: The present study evaluated the effect of mycophenolic acid on Japanese encephalitis virus (JEV) using an in vitro cytopathic effect inhibition assay, plaque reduction assay and virus yield reduction assay, and its therapeutic potential was also assessed in vivo in a mouse model. Results: Analysis of the results obtained in the in vitro and in vivo experiments suggests that mycophenolic acid has significant antiviral activity against JEV, with an IC50 of 3.1 µg/ml, a therapeutic index of 16 and a 75% protection against lethal challenge of JEV. Conclusion: The study concludes that this compound significantly inhibited the replication of JEV in vitro and protected mice in vivo.
- Published
- 2009
23. Ante mortem diagnosis of human rabies using saliva samples: comparison of real time and conventional RT-PCR techniques
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Shampur Narayan Madhusudana, Anita Desai, Joel P. Vasanth, T. Nagaraj, Anupa Kamat, and Vasanthapuram Ravi
- Subjects
Adult ,Male ,Saliva ,Adolescent ,Rabies ,Biology ,Diamines ,medicine.disease_cause ,Polymerase Chain Reaction ,chemistry.chemical_compound ,Virology ,TaqMan ,medicine ,Humans ,Benzothiazoles ,Organic Chemicals ,Child ,Lyssavirus ,Aged ,Fluorescent Dyes ,Reverse Transcriptase Polymerase Chain Reaction ,Rabies virus ,Rhabdoviridae ,Middle Aged ,biology.organism_classification ,medicine.disease ,Reverse transcription polymerase chain reaction ,Infectious Diseases ,chemistry ,Child, Preschool ,Immunology ,SYBR Green I ,Quinolines ,RNA, Viral ,Female - Abstract
Background: Rabies is an enzootic and fatal disease and is still a major problem in developing countries. Ante mortem diagnosis in human cases is necessary for medical management of the patient and to ensure appropriate post-exposure treatment of contacts. Both conventional RT-PCR and Real time PCR (TaqMan) have been described for the detection of rabies virus RNA from saliva and tissue respectively, however to date, there have been no studies comparing conventional and real time PCR assays for detection of rabies virus nucleic acid using saliva samples for ante mortem diagnosis. Objectives: In this study, we evaluated the utility of conventional RT-PCR and SYBR Green I Real time PCR in the ante mortem diagnosis of rabies using saliva samples. Study design: Saliva samples collected from twenty-four patients presenting with typical clinical manifestations of rabies were tested in the two assays. Results: Amongst the 24 samples tested, 21 samples (87.5%) were positive by either of the two molecular methods. Of these 21, rabies virus RNA was detected in 6/21 in the conventional RT-PCR assay while SYBR Green I Real time PCR could detect RNA in 18/21 samples. Conclusion: Real time PCR assay was more sensitive than conventional RT-PCR assay (sensitivity 75% versus 37%, p = 0.0189). This study highlights the utility of molecular diagnostic tests in establishing ante mortem diagnosis of rabies using saliva samples within a few hours.
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- 2005
24. Molecular Mimicry between Chikungunya Virus and Host Components: A Possible Mechanism for the Arthritic Manifestations.
- Author
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Reddy, Vijayalakshmi, Desai, Anita, Krishna, Shankar Susarla, and Vasanthapuram, Ravi
- Subjects
CHIKUNGUNYA virus ,ARTHRITIS ,IMMUNOREGULATION ,INFLAMMATION ,GLYCOPROTEINS ,HOST-virus relationships - Abstract
Background: Chikungunya virus (CHIKV), a reemerging pathogen causes a self limited illness characterized by fever, headache, myalgia and arthralgia. However, 10–20% affected individuals develop persistent arthralgia which contributes to considerable morbidity. The exact molecular mechanisms underlying these manifestations are not well understood. The present study investigated the possible occurrence of molecular mimicry between CHIKV E1 glycoprotein and host human components. Methodology: Bioinformatic tools were used to identify peptides of CHIKV E1 exhibiting similarity to host components. Two peptides (A&B) were identified using several bioinformatic tools, synthesised and used to validate the results obtained in silico. An ELISA was designed to assess the immunoreactivity of serum samples from CHIKV patients to these peptides. Further, experiments were conducted in a C57BL/6J experimental mouse model to investigate if peptide A and peptide B were indeed capable of inducing pathology. Findings: The serum samples showed reactivity of varying degrees, indicating that these peptides are indeed being recognized by the host immune system during CHIKV infection. Further, these peptides when injected into C57BL/6J mice were able to induce significant inflammation in the muscles of C57BL/6J mice, similar to that observed in animals that were injected with CHIKV alone. Additionally, animals that were primed initially with CHIKV followed by a subsequent injection of the CHIKV peptides exhibited enhanced inflammatory pathology in the skeletal muscles as compared to animals that were injected with peptides or virus alone. Collectively these observations validate the hypothesis that molecular mimicry between CHIKV E1 protein and host proteins does contribute to pathology in CHIKV infection. [ABSTRACT FROM AUTHOR]
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- 2017
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25. Proliferative response of human peripheral blood mononuclear cells to Japanese encephalitis virus
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Anita Desai, Mandaville Gourie-Devi, Akkepati Chandramuki, and Vasanthapuram Ravi
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Adult ,Male ,Cellular immunity ,Adolescent ,viruses ,Lymphocyte ,Immunology ,Enzyme-Linked Immunosorbent Assay ,Biology ,Antibodies, Viral ,Lymphocyte Activation ,Microbiology ,Peripheral blood mononuclear cell ,Virus ,Immune system ,Viral Envelope Proteins ,Virology ,medicine ,Humans ,Lymphocytes ,Child ,Encephalitis, Japanese ,Antigens, Viral ,Hemagglutination, Viral ,Encephalitis Virus, Japanese ,Immunity, Cellular ,Infant ,Japanese encephalitis ,Middle Aged ,medicine.disease ,biology.organism_classification ,Flavivirus ,medicine.anatomical_structure ,Immunoglobulin M ,Child, Preschool ,biology.protein ,Female ,Antibody - Abstract
Cell-mediated immune response to Japanese encephalitis virus (JEV) and its purified envelope (E) protein was measured in 45 laboratory confirmed JE patients using a proliferation assay of peripheral blood mononuclear cells (PBMC). In parallel, JEV-specific IgM antibodies were measured by ELISA. No correlation was observed between the antibody response and results of the lymphocyte proliferation assay. Only 11 of the 42 patients positive in the antibody test were positive in the proliferation assay, and PBMC from 14/45 (31%) patients did not respond to either phytohemagglutinin and to JEV and/or its purified E protein antigen. No correlation was observed between the cell-mediated immune response and the final clinical outcome (fatality vs. recovery).
- Published
- 1995
26. Development and evaluation of a competitive ELISA for estimation of rabies neutralizing antibodies after post-exposure rabies vaccination in humans
- Author
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Kader Muhamuda, Vasanthapuram Ravi, and Shampur Narayan Madhusudana
- Subjects
Microbiology (medical) ,medicine.drug_class ,Rabies ,Fluorescent Antibody Technique ,Enzyme-Linked Immunosorbent Assay ,Monoclonal antibody ,Antibodies, Viral ,Sensitivity and Specificity ,Virus ,Neutralization ,C-ELISA ,Mice ,Neutralization Tests ,medicine ,Animals ,Humans ,Post-exposure vaccination ,biology ,business.industry ,Antibody titer ,General Medicine ,medicine.disease ,Virology ,Vaccination ,Titer ,Infectious Diseases ,Rabies Vaccines ,Immunology ,biology.protein ,Antibody ,business - Abstract
SummaryObjectivesCurrently three tests are approved for the estimation of neutralizing antibodies after rabies vaccination: the mouse neutralization test (MNT), the rapid fluorescent focus inhibition test (RFFIT), and the fluorescent antibody virus neutralization (FAVN) test. Performance of these tests requires a lot of expertise and is generally carried out in reference laboratories and, hence, they are not available to many people. The aim of the present study was to develop and evaluate a competitive ELISA (C-ELISA) for estimation of neutralizing antibodies in order to make this testing more widely available.MethodsThe C-ELISA was designed based on competition between a murine neutralizing monoclonal antibody (Mab) and the antibodies in serum of vaccinated people. The test was initially standardized using known negative and known positive serum samples for determining the optimal dilution of the Mab as well as the cut-off value (%) for ascertaining the level of inhibition. Nine hundred and ninety serum samples were tested from 250 people who had been administered purified chick embryo cell vaccine (PCECV). Serum samples were collected on days 0, 14, 30 and 90 post-vaccination, and were tested by C-ELISA.ResultsAll the serum samples that were positive by RFFIT were also positive by C-ELISA. The titers obtained with C-ELISA were marginally higher than the RFFIT titers, but a significant correlation was noted between the two tests (r=0.897). None of the negative controls were detected to be positive for rabies antibodies by either of these tests. Therefore the C-ELISA was found to be 100% specific and sensitive in comparison to RFFIT. Further, the initial rise and fall of antibody titers on different days post-vaccination was comparable for both tests.ConclusionsThe C-ELISA described herein can be used to quantify rabies neutralizing antibody levels after vaccination. This test is simple and can be conveniently used under field conditions for monitoring seroconversion after post-exposure rabies vaccination. Moreover it does not require handling of infectious virus by the end user.
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27. Laboratory diagnosis of japanese encephalitis using monoclonal antibodies and correlation of findings with the outcome
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Vasanthapuram Ravi, S. Vanajakshi, Anke Gowda, and A. Chandramuki
- Subjects
Adolescent ,medicine.drug_class ,viruses ,Antibodies, Viral ,Monoclonal antibody ,Virus ,Mice ,Cerebrospinal fluid ,Antigen ,Virology ,medicine ,Animals ,Humans ,Child ,Encephalitis, Japanese ,Antigens, Viral ,Encephalitis Virus, Japanese ,biology ,Antibodies, Monoclonal ,Infant ,Japanese encephalitis ,medicine.disease ,biology.organism_classification ,Flavivirus ,Infectious Diseases ,Immunoglobulin M ,Child, Preschool ,Immunoglobulin G ,Immunology ,biology.protein ,Viral disease ,Antibody - Abstract
Detection of virus, viral antigen, and class-specific antibody was carried out in cerebrospinal fluid (CSF) and sera of 27 children with Japanese encephalitis. The diagnosis could be confirmed in 78.57% of cases (22/27) by demonstration of virus-specific IgM in CSF (15/22), viral antigen in CSF (5/22), or by virus isolation (2/22). Absence of virus specific IgM in CSF was associated with a fatal outcome (P = 0.05).
- Published
- 1989
28. Identification of unique B/C recombinant strains of HIV-1 in the southern state of Karnataka, India
- Author
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Narayana Jayasuryan, Udaykumar Ranga, Nagadenahalli B. Siddappa, Prashanta Kumar Dash, Anita Mahadevan, Parthasarathy Satishchandra, Vasanthapuram Ravi, Susarla K. Shankar, and Anita Desai
- Subjects
Adult ,Male ,Adolescent ,Immunology ,Human immunodeficiency virus (HIV) ,India ,HIV Infections ,Biology ,medicine.disease_cause ,Virus ,law.invention ,law ,medicine ,Immunology and Allergy ,Humans ,Phylogeny ,Recombination, Genetic ,Middle Aged ,biology.organism_classification ,Virology ,Infectious Diseases ,Lentivirus ,Recombinant DNA ,HIV-1 ,Female ,Viral disease - Abstract
We characterized the molecular nature of a large number of primary HIV-1 isolates in the four southern states of India. In addition to confirming a predominance of subtype C infection, for the first time we identified three B/C recombinant viruses in a subset of 115 samples. Unexpectedly, env sequences of two of the three B/C recombinants phylogenetically clustered with subtype B strains of the USA. The determination of the real incidence of the recombinant viruses is of importance.
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