DNA/MVA vaccine for HIV type 1: effects of codon-optimization and the expression of aggregates or virus-like particles on the immunogenicity of the DNA prime

Recently, a vaccine consisting of DNA priming followed by boosting with modified vaccinia Ankara (MVA) has provided long-term protection of rhesus macaques against a virulent challenge with a chimera of simian and human immunodeficiency viruses. Here, we report studies on the development of the DNA component for a DNA/MVA HIV vaccine for humans. Specifically, we assess the ability of a codon-optimized Gag-expressing DNA and two noncodon-optimized Gag-Pol-Env-expressing DNAs to prime the MVA booster dose. The codon-optimized DNA expressed virus-like particles (VLPs), whereas one of the noncodon-optimized DNAs expressed VLPs and the other expressed aggregates of HIV proteins. The MVA boost expressed Gag-Pol and Env and produced VLPs. Immunogenicity studies in macaques used one intramuscular prime with 600 microg of DNA and two intramuscular boosts with 1 x 10(8) pfu of MVA at weeks 8 and 30. The codon-optimized and noncodon-optimized DNAs proved similar in their ability to prime anti-Gag T cell responses. The aggregate and VLP-expressing Gag-Pol-Env DNAs also showed no significant differences in their ability to prime anti-Env Ab responses. The second MVA booster dose did not increase the peak CD4 and CD8 T cell responses, but increased anti-Env Ab titers by 40- to 90-fold. MVA-only immunizations elicited 10-100 times lower frequencies of T cells and 2-4 lower titers of anti-Env Ab than the Gag-Pol-Env DNA/MVA immunizations. Based on the breadth of the T cell response and a trend toward higher titers of anti-Env Ab, we are moving forward with human trials of the noncodon-optimized VLP-expressing DNA.     

Intersectional stigma and psychosocial well-being among MSM living with HIV in Guangxi,China

ABSTRACT

The existing literature suggests a negative impact of intersectional stigma on multiple aspects of psychosocial well-being among individuals with multiple stigmatized identities. However, such impact remains poorly understood. This study aims to investigate the association between intersectional stigma and psychosocial well-being among 193 men who have sex with men (MSM) living with HIV. Based on their responses to measures of HIV-related stigma and sexual and gender minority (SGM) stigma, the participants were grouped into “high” vs “low” on each type of stigma. The General Linear Model (GLM) was used to analyze the main and interaction effect of two types of stigma on multiple psychosocial measures. Our results indicated a significant interaction effect of two types of stigma on depression, anxiety, quality of life, and psychological resilience after controlling for key socio-demographic covariates. The findings suggest that experiencing both HIV-related stigma and SGM stigma may synergistically lead to poor psychosocial well-being among MSM in a more profound manner than experiencing only one type of stigma. It is critical for researchers and clinicians to consider the patients’ multiple stigmatized identities, develop effective intervention strategies, and improve the psychosocial well-being of MSM living with HIV in China and other cultural settings.     

Behavioural strategies to reduce HIV transmission: how to make them work better

This paper makes five key points. First is that the aggregate effect of radical and sustained behavioural changes in a sufficient number of individuals potentially at risk is needed for successful reductions in HIV transmission. Second, combination prevention is essential since HIV prevention is neither simple nor simplistic. Reductions in HIV transmission need widespread and sustained efforts, and a mix of communication channels to disseminate messages to motivate people to engage in a range of options to reduce risk. Third, prevention programmes can do better. The effect of behavioural strategies could be increased by aiming for many goals (eg, delay in onset of first intercourse, reduction in number of sexual partners, increases in condom use, etc) that are achieved by use of multilevel approaches (eg, couples, families, social and sexual networks, institutions, and entire communities) with populations both uninfected and infected with HIV. Fourth, prevention science can do better. Interventions derived from behavioural science have a role in overall HIV-prevention efforts, but they are insufficient when used by themselves to produce substantial and lasting reductions in HIV transmission between individuals or in entire communities. Fifth, we need to get the simple things right. The fundamentals of HIV prevention need to be agreed upon, funded, implemented, measured, and achieved. That, presently, is not the case.     

Intestinal lipoprotein overproduction, a newly recognized component of insulin resistance, is ameliorated by the insulin sensitizer rosiglitazone: studies in the fructose-fed Syrian golden hamster

We investigated whether intestinal lipoprotein overproduction in a fructose-fed, insulin-resistant hamster model is prevented with insulin sensitization. Syrian Golden hamsters were fed either chow, 60% fructose for 5 wk, chow for 5 wk with the insulin sensitizer rosiglitazone added for the last 3 wk, or 60% fructose plus rosiglitazone. In vivo Triton studies showed a 2- to 3-fold increase in the large (Svedberg unit > 400) and smaller (Sf 100-400) triglyceride-rich lipoprotein particle apolipoprotein B48 (apoB48) but not triglyceride secretion with fructose feeding in the fasted state (P < 0.01) and partial normalization with rosiglitazone in fructose-fed hamsters. Ex vivo pulse-chase labeling of enterocytes confirmed the oversecretion of apoB48 lipoproteins with fructose feeding. Intestinal lipoprotein oversecretion was associated with increased expression of microsomal triglyceride transfer protein expression. With rosiglitazone treatment of fructose-fed hamsters, there was approximately 50% reduction in apoB48 secretion from primary cultured enterocytes and amelioration of the elevated microsomal triglyceride transfer protein mass and activity in fructose-fed hamsters. In contrast, in the postprandial state, the major differences between nutritional and drug intervention protocols were evident in triglyceride-rich lipoprotein triglyceride and not apoB48 secretion rates. The data suggest that intestinal lipoprotein overproduction can be ameliorated with the insulin sensitizer rosiglitazone.     

Outcome prediction in chest injury by a mathematical search and display program

OBJECTIVE: This study applies a stochastic or probability search and display model to prospectively predict outcome and to evaluate therapeutic effects in a consecutively monitored series of 396 patients with severe thoracic and thoracoabdominal injuries. STUDY DESIGN: Prospective observational study of outcome prediction using noninvasive hemodynamic monitoring by previously designed protocols and tested against actual outcome at hospital discharge in a level 1 trauma service of a university-run, inner-city public hospital. METHODS: Cardiac index (CI), heart rate (HR), mean arterial pressure (MAP), arterial oxygen saturation measured by pulse oximetry (Sp(O2)), transcutaneous oxygen tension (PtC(O2)), and transcutaneous carbon dioxide tension (Ptc(CO2)) were monitored beginning shortly after admission to the emergency department. The stochastic search and display model with a decision support program based on noninvasive hemodynamic monitoring was applied to 396 severely ill patients with major thoracic and thoracoabdominal trauma. The survival probability (SP) was calculated during initial resuscitation continuously until patients were stabilized, and compared with the actual outcome when the patient was discharged from the hospital usually a week or more later. RESULTS: The CI, Sp(O2), Ptc(O2), and MAP were appreciably higher in survivors than in nonsurvivors. HR and Ptc(CO2) were higher in the nonsurvivors. The calculated SP in the first 24-h observation period of survivors of chest wounds averaged 83 +/- 18% (+/- SD) and 62 +/- 19% for nonsurvivors. Misclassifications were 9.6%. The relative effects of alternative therapies were evaluated before and after therapy, using hemodynamic monitoring and SP as criteria. CONCLUSIONS: Noninvasive hemodynamic monitoring with an information system provided a feasible approach to early outcome predictions and therapeutic decision support.     

Estrogens,but not androgens,regulate expression and functional activity of oxytocin receptor in rabbit epididymis

Previous binding and contractility studies indicate that oxytocin (OT) receptors are present in rabbit epididymis. To investigate the effect of changing endocrine milieu on OT responsiveness, we induced hypogonadism (hypo) in rabbits with a single administration of a long-acting GnRH analog, triptorelin, and we replaced hypogonadal rabbits with different sex steroids. After 2 months from triptorelin administration, testosterone (T) plasma levels were decreased and OT responsiveness abolished. Administration of T to hypo rabbits restored T plasma levels but not OT sensitivity. Because Western blot analysis indicated that both estrogen receptors and aromatase are expressed in the epididymis, we treated hypo rabbits with estradiol valerate (E2v). E2v not only completely restored OT responsiveness but also even amplified it. Accordingly, Northern and Western blot analysis indicated that both OT receptor gene and protein were strongly induced by E2v but not by T. Surprisingly, also the class I estrogen receptor antagonist, tamoxifen restored OT sensitivity in hypo rabbits. To verify whether endogenous estradiol is involved in the regulation of OT receptor responsiveness, we treated intact rabbits with an aromatase inhibitor, letrozole. Blocking aromatase activity almost completely abolished OT sensitivity. These findings suggest a new function of estrogens in the male: regulation of OT responsiveness in epididymis.     

The Value of Claims-Based Nontraditional Risk Factors in Predicting Long-term Mortality After MitraClip Procedure

Background

We sought to identify nontraditional risk factors coded in administrative claims data and evaluate their ability to improve prediction of long-term mortality in patients undergoing percutaneous mitral valve repair.

Highly attenuated smallpox vaccine protects mice with and without immune deficiencies against pathogenic vaccinia virus challenge

Modified vaccinia virus Ankara (MVA), developed >30 years ago as a highly attenuated candidate smallpox vaccine, was recloned from a 1974 passage and evaluated for safety and immunogenicity. Replication of MVA is impaired in most mammalian cells, and we found that mice with severe combined immunodeficiency disease remained healthy when inoculated with MVA at 1,000 times the lethal dose of vaccinia virus derived from the licensed Dryvax vaccine seed. In BALB/c mice inoculated intramuscularly with MVA, virus-specific CD8+ T cells and antibodies to purified virions and membrane protein components of the intracellular and extracellular infectious forms of vaccinia virus were induced in a dose-dependent manner. After one or two inoculations of MVA, the T cell numbers and antibody titers equaled or exceeded those induced by percutaneous injection of Dryvax. Antibodies induced by MVA and Dryvax were neutralizing and inhibited virus spread in cultured cells. Furthermore, vaccinated mice were protected against lethal intranasal challenge with a pathogenic vaccinia virus. B cell-deficient mice unable to generate antibodies and beta2-microglobulin-deficient mice unable to express MHC class I molecules for a CD8+ T cell response were also protectively vaccinated by MVA. In contrast, mice with decreased CD4 or MHC class II expression and double-knockout mice deficient in MHC class I- and II-restricted activities were poorly protected or unprotected. This study confirmed the safety of MVA and demonstrated that the overlapping immune responses protected normal and partially immune-deficient animals, an encouraging result for this candidate attenuated smallpox vaccine.     

A new member of the tumor necrosis factor/nerve growth factor receptor family inhibits T cell receptor-induced apoptosis

By comparing untreated and dexamethasone-treated murine T cell hybridoma (3DO) cells by the differential display technique, we have cloned a new gene, GITR (glucocorticoid-induced tumor necrosis factor receptor family-related gene) encoding a new member of the tumor necrosis factor/nerve growth factor receptor family. GITR is a 228-amino acids type I transmembrane protein characterized by three cysteine pseudorepeats in the extracellular domain and similar to CD27 and 4-1BB in the intracellular domain. GITR resulted to be expressed in normal T lymphocytes from thymus, spleen, and lymph nodes, although no expression was detected in other nonlymphoid tissues, including brain, kidney, and liver. Furthermore, GITR expression was induced in T lymphocytes upon activation by anti-CD3 mAb, Con A, or phorbol 12-myristate 13-acetate plus Ca-ionophore treatment. The constitutive expression of a transfected GITR gene induced resistance to anti-CD3 mAb-induced apoptosis, whereas antisense GITR mRNA expression lead to increased sensitivity. The protection toward T cell receptor-induced apoptosis was specific, because other apoptotic signals (Fas triggering, dexamethasone treatment, or UV irradiation) were not modulated by GITR transfection. Thus, GITR is a new member of tumor necrosis factor/nerve growth factor receptor family involved in the regulation of T cell receptor-mediated cell death.