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UnlabelledCellular immunity is pivotal in HIV-1 pathogenesis but is hampered by viral sequence diversity. An approach to minimize this diversity is to focus immunity on conserved proteome sequences; therefore, we selected four relatively conserved regions (Gag amino acids 148 to 214 and 250 to 335, Env amino acids 521 to 606, and Nef amino acids 106 to 148), each created in three mosaics, to provide better coverage of M-group HIV-1 sequences. A conserved-region vaccine (CRV) delivering genes for these four regions as equal mixtures of three mosaics each (each region at a separate injection site) was compared to a whole-protein vaccine (WPV) delivering equimolar amounts of genes for whole Gag, Env, and Nef as clade B consensus sequences (separate injection sites). Three rhesus macaques were vaccinated via three DNA primes and a recombinant adenovirus type 5 boost (weeks 0, 4, 8, and 24, respectively). Although CRV inserts were about one-fifth that of WPV, the CRV generated comparable-magnitude blood CD4+ and CD8+ T lymphocyte responses against Gag, Env, and Nef. WPV responses preferentially targeted proteome areas outside the selected conserved regions in direct proportion to sequence lengths, indicating similar immunogenicities for the conserved regions and the outside regions. The CRV yielded a conserved-region targeting density that was approximately 5-fold higher than that of the WPV. A similar pattern was seen for bronchoalveolar lymphocytes, but with quadruple the magnitudes seen in blood. Overall, these findings demonstrate that the selected conserved regions are highly immunogenic and that anatomically isolated vaccinations with these regions focus immunodominance compared to the case for full-length protein vaccination.ImportanceHIV-1 sequence diversity is a major barrier limiting the capability of cellular immunity to contain infection and the ability of vaccines to match circulating viral sequences. To date, vaccines tested in humans have delivered whole proteins or genes for whole proteins, and it is unclear whether including only conserved sequences would yield sufficient cellular immunogenicity. We tested a vaccine delivering genes for four small conserved HIV-1 regions compared to a control vaccine with genes for whole Gag, Env, and Nef. Although the conserved regions ranged from 43 to 86 amino acids and comprised less than one-fifth of the whole Gag/Env/Nef sequence, the vaccines elicited equivalent total magnitudes of both CD4+ and CD8+ T lymphocyte responses. These data demonstrate the immunogenicity of these small conserved regions and the potential for a vaccine to steer immunodominance toward conserved epitopes.

Chronic-phase HIV and simian immunodeficiency virus (SIV) replication is reduced by as much as 10,000-fold in elite controllers (ECs) compared with typical progressors (TPs), but sufficient viral replication persists in EC tissues to allow viral sequence evolution and induce excess immune activation. Here we show that productive SIV infection in rhesus monkey ECs, but not TPs, is markedly restricted to [CD4.sup.+] follicular helper T ([T.sub.FH]) cells, suggesting that these EC monkeys' highly effective SIV-specific [CD8.sup.+] T cells can effectively clear productive SIV infection from extrafollicular sites, but their relative exclusion from B cell follicles prevents their elimination of productively infected [T.sub.FH] cells. [CD8.sup.+] lymphocyte depletion in EC monkeys resulted in a dramatic re-distribution of productive SIV infection to non-[T.sub.FH] cells, with restriction of productive infection to [T.sub.FH] cells resuming upon [CD8.sup.+] T cell recovery. Thus, B cell follicles constitute 'sanctuaries' for persistent SIV replication in the presence of potent anti-viral [CD8.sup.+] T cell responses, potentially complicating efforts to cure HIV infection with therapeutic vaccination or T cell immunotherapy., HIV and its nonhuman-primate counterpart, SIV, use both specific genetic mechanisms and extraordinary genetic malleability and functional plasticity to either evade or escape innate and adaptive immunity (1,2). Indeed, the [...]

The sustained growth of the market for ophthalmic medical devices has increased the demand for alternatives to animal testing for the evaluation of eye irritation. The International Organization for Standardization has acknowledged the need to develop novel in vitro tests to replace animal testing. Here, we evaluated the applicability of an alternative method based on a human corneal model to test the safety of ophthalmic medical devices. 2-Hydroxyethyl methacrylate (HEMA) and Polymethyl methacrylate (PMMA), which are used to fabricate contact lenses, were used as base materials. These materials were blended with eye irritant and non-irritant chemicals specified in the OECD Test Guideline (TG) 492 and Globally Harmonized System (GHS) classification. Then, three GLP-certified laboratories performed three replicates using the developed method using 3D reconstructed human cornea epithelium, MCTT HCETM. OECD TG 492 describes the procedure used to evaluate the eye hazard potential of the test chemical based on its ability to induce cytotoxicity in a reconstructed human cornea-like epithelium (RhCE) tissue. Results: The within-laboratory reproducibility (WLR) and between-laboratory reproducibility (BLR) were both 100%. When a polar extraction solvent was used, the sensitivity, specificity, and accuracy were all 100% in each laboratory. When a non-polar extraction solvent was used, the sensitivity was 80%, the specificity was 100%, and the accuracy was 90%. The proposed method exhibited excellent reproducibility and predictive capacity within and between laboratories. Therefore, the proposed method using the MCTT HCETM model could be used to evaluate eye irritation caused by ophthalmic medical devices. [ABSTRACT FROM AUTHOR]

In Alzheimer's disease (AD), memory impairment is the most prominent feature that afflicts patients and their families. Although reactive astrocytes have been observed around amyloid plaques since the disease was first described, their role in memory impairment has been poorly understood. Here, we show that reactive astrocytes aberrantly and abundantly produce the inhibitory gliotransmitter GABA by monoamine oxidase-B (Maob) and abnormally release GABA through the bestrophin 1 channel. In the dentate gyrus of mouse models of AD, the released GABA reduces spike probability of granule cells by acting on presynaptic GABA receptors. Suppressing GABA production or release from reactive astrocytes fully restores the impaired spike probability, synaptic plasticity, and learning and memory in the mice. In the postmortem brain of individuals with AD, astrocytic GABA and MAOB are significantly upregulated. We propose that selective inhibition of astrocytic GABA synthesis or release may serve as an effective therapeutic strategy for treating memory impairment in AD., AD is the most common cause of dementia and is characterized by a progressive decline of memory and other cognitive functions (1). To date, the causes of memory impairment have [...]

A novel di-carboxyiic acid curing agent (DACA) was successfully synthesized and cured with three different epoxy resins: glycidyl end-capped poly(bisphenol-A-coepichlorohydrin) (pDGEBA, [M.sub.n] 377), N,N-diglycidyl-4-glycidyloxyaniline (TGAP), and 4,4'-methylenebis(N,N-diglycidylaniline) (TGDDM). The cured epoxy exhibited excellent thermal stability, which was indicated by high initial degradation temperature ([T.sub.id]) and char yield. The [T.sub.id] values of cured epoxy were in the range of 327-338°C, and the char yields increased with increasing epoxy functionality. The char yields of cured DACA/ pDGEPA, DACA/TGAP, and DACA/TGDDM samples were 21.1, 60.4, and 66.9%, respectively. In addition, the cured epoxy samples also showed low coefficients of thermal expansion and high storage moduli (E'), which were around 60 ppm/°C and 2800 MPa, respectively. The failure surfaces were ductile and rough, so the cured epoxy samples are expected to have high fracture toughness and impact strength. POLYM. ENG. SCI., 54:695-703, 2014. © 2013 Society of Plastics Engineers, INTRODUCTION Epoxy resins are a versatile group of thermoset polymers that have excellent properties, such as stiffness, strength, chemical resistance, low dielectric constant and loss, adhesiveness to substrates, and thermal [...]

Live attenuated simian immunodeficiency virus (SIV) vaccines (LAVs) remain the most efficacious of all vaccines in nonhuman primate models of HIV and AIDS, yet the basis of their robust protection remains poorly understood. Here we show that the degree of LAV-mediated protection against intravenous wild-type SIVmac239 challenge strongly correlates with the magnitude and function of SIV-specific, effector-differentiated T cells in the lymph node but not with the responses of such T cells in the blood or with other cellular, humoral and innate immune parameters. We found that maintenance of protective T cell responses is associated with persistent LAV replication in the lymph node, which occurs almost exclusively in follicular helper T cells. Thus, effective LAVs maintain lymphoid tissue-based, effector-differentiated, SIV-specific T cells that intercept and suppress early wild-type SIV amplification and, if present in sufficient frequencies, can completely control and perhaps clear infection, an observation that provides a rationale for the development of safe, persistent vectors that can elicit and maintain such responses., It has been two decades since the first report that LAV administration can completely protect rhesus macaques from subsequent challenge with highly pathogenic, wild-type SIV(1), a degree of efficacy that [...]