Compositions Comprising Human Immunodeficiency Virus Tat Adsorbed to the Surface of Anionic Nanoparticles

Non-denatured, recombinant human immunodeficiency virus (HIV) Tat that is free of bacterial RNA and endotoxin is employed in an anti-HIV vaccine. A process of producing the recombinant Tat protein includes steps for removing bacterial RNA from the recombinant Tat and for removing endotoxin from the recombinant Tat protein. A Tat-adsorbed nanoparticle formulation and method of making the same. A method of vaccinating against and/or treating HIV infection comprises administering to a subject in need of such vaccination or treatment an immune-response inducing effective amount of the recombinant Tat protein

JC Virus Antibody and Viremia as Predictors of Progressive Multifocal Leukoencephalopathy in Human Immunodeficiency Virus-1-Infected Individuals

We examined whether prediagnostic John Cunningham virus (JCV) antibodies and viremia are predictors of progressive multifocal leukoencephalopathy (PML) in 83 PML cases and 240 human immunodeficiency virus (HIV) disease-matched controls. JCV viremia was not predictive of PML, but some patients showed higher anti-JCV immunoglobulin G (IgG) responses 6 months prior to diagnosi

Characterization of novel human endogenous retrovirus structures on chromosomes 6 and 7

Human endogenous retroviruses (HERV) represent nearly 8% of the human genome. Of these, HERV-K subtype HML-2 is a transposable element that plays a critical role in embryonic development and in the pathogenesis of several diseases. Quantification and characterization of these multiple HML-2 insertions in the human chromosome has been challenging due to their size, sequence homology with each other, and their repetitive nature. We examined a cohort of 222 individuals for HML-2 proviruses 6q14.1 and 7p22.1a, two loci that are capable of producing full-length viral proteins and have been previously implicated in several cancers, autoimmune disorders and neurodegenerative diseases, using long-read DNA sequencing. While the reference genome for both regions suggests these two loci are structurally dissimilar, we found that for both loci about 5% of individuals have a unique tandem repeat-like sequence (three long terminal repeat sequences sandwiching two internal, potentially protein coding sequences), while most individuals have a standard proviral structure (one internal region sandwiched by two long terminal repeats). Moreover, both proviruses can make full-length, or nearly full-length, HERV-K proteins in multiple transcription orientations. The amino acid sequences from different loci in the same transcriptional orientation share sequence homology with each other. These results demonstrate a clear, previously unreported, relationship between HML-2 loci 6q14.1 and 7p22.1a and highlight the utility of long-read sequencing to study repetitive elements. Future studies need to determine if these polymorphisms determine genetic susceptibility to diseases that are associated with them

Lipid nanoparticles with accessible nickel as a vaccine delivery system for single and multiple his-tagged HIV antigens

Lipid-based nanoparticles (NPs) with a small amount of surface-chelated nickel (Ni-NPs) were developed to easily formulate the human immunodeficiency virus (HIV) his-tagged Tat (his-Tat) protein, as well as to formulate and co-deliver two HIV antigens (his-p24 and his-Nef) on one particle. Female BALB/c mice were immunized by subcutaneous injection with his-Tat/Ni-NP formulation (1.5 μg his-Tat/mouse) and control formulations on day 0 and 14. The day 28 anti-Tat specific immunoglobulin G titer with his-Tat/Ni-NPs was significantly greater than that with Alum/his-Tat. Furthermore, splenocytes from his-Tat/Ni-NP-immunized mice secreted significantly higher IFN-γ than those from mice immunized with Alum/his-Tat. Although Ni-NPs did not show better adjuvant activity than Tat-coated anionic NPs made with sodium dodecyl sulfate (SDS/NPs), they were less toxic than SDS/NPs. The initial results indicated that co-immunization of mice using his-p24/his-Nef/Ni-NP induced greater antibody response compared to using Alum/his-p24/his-Nef. Co-delivery of two antigens using Ni-NPs also increased the immunogenicity of individual antigens compared to delivery of a single antigen by Ni-NPs. In conclusion, Ni-NPs are an efficient delivery system for HIV vaccines including both single antigen delivery and multiple antigen co-delivery

Gonadal steroids differentially modulate neurotoxicity of HIV and cocaine: testosterone and ICI 182,780 sensitive mechanism

BACKGROUND: HIV Associated Dementia (HAD) is a common complication of human immunodeficiency virus (HIV) infection that erodes the quality of life for patients and burdens health care providers. Intravenous drug use is a major route of HIV transmission, and drug use is associated with increased HAD. Specific proteins released as a consequence of HIV infection (e.g., gp120, the HIV envelope protein and Tat, the nuclear transactivating protein) have been implicated in the pathogenesis of HAD. In primary cultures of human fetal brain tissue, subtoxic doses of gp120 and Tat are capable of interacting with a physiologically relevant dose of cocaine, to produce a significant synergistic neurotoxicity. Using this model system, the neuroprotective potential of gonadal steroids was investigated. RESULTS: 17β-Estradiol (17β-E(2)), but not 17α-estradiol (17α-E(2)), was protective against this combined neurotoxicity. Progesterone (PROG) afforded limited neuroprotection, as did dihydrotestosterone (DHT). The efficacy of 5α-testosterone (T)-mediated neuroprotection was robust, similar to that provided by 17β-E(2. )In the presence of the specific estrogen receptor (ER) antagonist, ICI-182,780, T's neuroprotection was completely blocked. Thus, T acts through the ER to provide neuroprotection against HIV proteins and cocaine. Interestingly, cholesterol also demonstrated concentration-dependent neuroprotection, possibly attributable to cholesterol's serving as a steroid hormone precursor in neurons. CONCLUSION: Collectively, the present data indicate that cocaine has a robust interaction with the HIV proteins gp120 and Tat that produces severe neurotoxicity, and this toxicity can be blocked through pretreatment with ER agonists

Neuropathology of HIV/AIDS with an overview of the Indian scene

Neurological manifestations of HIV infection and AIDS are being recognized with a frequency that parallels the increasing number of AIDS cases. Next to sub-Saharan Africa, India has the second largest burden of HIV related pathology, essentially caused by HIV-1 clade C in both the geographic locales, in contrast to USA and Europe. But the true prevalence of HIV related neuroinfections and pathology is not available due to inadequate medical facilities, social stigma and ignorance that lead to underdiagnosis. Neurotuberculosis, followed by cryptococcosis and toxoplasmosis in various combinations are the major neuropathologies reflecting the endemicity and manifesting clinically by reactivation of latent infection. Discordance in the clinical prevalence of various infections, when compared to pathological studies highlight similarities in clinical, radiological modalities of diagnosis and inherent problems in establishing definitive diagnosis. Viral infections appear to be relatively rare. Inspite of heavy burden of HIV/AIDS, HIV associated neoplasia is infrequent, including primary CNS lymphomas. HIV encephalitis and HIV associated dementia are considered infrequent, though systematic studies have just been initiated in various centres. Peripheral neuropathy characteristically manifests with vasculitic neuropathy while diffuse infiltrative lymphocytosis syndrome (DILS) involving nerves has not been reported from India. Spinal cord pathology including vacuolar myelopathy is rare, even in asymptomatic cases. Till now the AIDS cases in India were drug naÏve but a new cohort of cases following initiation of HAART therapy as a national policy is soon emerging, altering the biology and evolution of HIV/AIDS in India. Lacunae in the epidemiology, diagnosis and study of biology of HIV/AIDS are outlined for future research

Impairment of adult hippocampal neural progenitor proliferation by methamphetamine: role for nitrotyrosination

Methamphetamine (METH) abuse has reached epidemic proportions, and it has become increasingly recognized that abusers suffer from a wide range of neurocognitive deficits. Much previous work has focused on the deleterious effects of METH on mature neurons, but little is known about the effects of METH on neural progenitor cells (NPCs). It is now well established that new neurons are continuously generated from NPCs in the adult hippocampus, and accumulating evidence suggests important roles for these neurons in hippocampal-dependent cognitive functions. In a rat hippocampal NPC culture system, we find that METH results in a dose-dependent reduction of NPC proliferation, and higher concentrations of METH impair NPC survival. NPC differentiation, however, is not affected by METH, suggesting cell-stage specificity of the effects of METH. We demonstrate that the effects of METH on NPCs are, in part, mediated through oxidative and nitrosative stress. Further, we identify seventeen NPC proteins that are post-translationally modified via 3-nitrotyrosination in response to METH, using mass spectrometric approaches. One such protein was pyruvate kinase isoform M2 (PKM2), an important mediator of cellular energetics and proliferation. We identify sites of PKM2 that undergo nitrotyrosination, and demonstrate that nitration of the protein impairs its activity. Thus, METH abuse may result in impaired adult hippocampal neurogenesis, and effects on NPCs may be mediated by protein nitration. Our study has implications for the development of novel therapeutic approaches for METH-abusing individuals with neurologic dysfunction and may be applicable to other neurodegenerative diseases in which hippocampal neurogenesis is impaired