Background-In the Step Study, the MRKAd5 HIV-1 gag/pol/nef vaccine did not lower postinfection plasma viremia, and HIV-1 incidence was higher in vaccine-treated than placebo-treated males with pre-existing adenovirus serotype 5 (Ad5) immunity. We evaluated vaccine-induced immunity and its potential contributions to infection risk.

MVA62 was well tolerated and elicited different patterns of T cell and Ab responses when administered alone or in combination with the JS7 DNA vaccine.

BackgroundThe safety and immunogenicity of a vaccine regimen consisting of a 6-plasmid HIV-1 DNA prime (envA, envB, envC, gagB, polB, nefB) boosted by a recombinant adenovirus serotype-5 (rAd5) HIV-1 with matching inserts was evaluated in HIV-seronegative participants from South Africa, United States, Latin America and the Caribbean.Methods480 participants were evenly randomized to receive either: DNA (4 mg IM by Biojector) at 0, 1 and 2 months, followed by rAd5 (1010 PU IM by needle/syringe) at 6 months; or placebo. Participants were monitored for reactogenicity and adverse events throughout the 12-month study. Peak and duration of HIV-specific humoral and cellular immune responses were evaluated after the prime and boost.ResultsThe vaccine was well tolerated and safe. T-cell responses, detected by interferon-γ (IFN-γ) ELISpot to global potential T-cell epitopes (PTEs) were observed in 70.8% (136/192) of vaccine recipients overall, most frequently to Gag (54.7%) and to Env (54.2%). In U.S. vaccine recipients T-cell responses were less frequent in Ad5 sero-positive versus sero-negative vaccine recipients (62.5% versus 85.7% respectively, p = 0.035). The frequency of HIV-specific CD4+ and CD8+ T-cell responses detected by intracellular cytokine staining were similar (41.8% and 47.2% respectively) and most secreted ≥2 cytokines. The vaccine induced a high frequency (83.7%–94.6%) of binding antibody responses to consensus Group M, and Clades A, B and C gp140 Env oligomers. Antibody responses to Gag were elicited in 46% of vaccine recipients.ConclusionThe vaccine regimen was well-tolerated and induced polyfunctional CD4+ and CD8+ T-cells and multi-clade anti-Env binding antibodies.Trial Registration:ClinicalTrials.gov NCT00125970

Recombinant viruses hold promise as vectors for vaccines to prevent infectious diseases with significant global health impacts. One of their major limitations is that preexisting anti-vector neutralizing antibodies can reduce T cell responses to the insert antigens; however, the impact of vector-specific cellular immunity on subsequent insert-specific T cell responses has not been assessed in humans. Here, we have identified and compared adenovirus-specific and HIV-specific T cell responses in subjects participating in two HIV-1 vaccine trials using a vaccine vectored by adenovirus serotype 5 (Ad5). Higher frequencies of pre-immunization adenovirus-specific CD4 + T cells were associated with substantially decreased magnitude of HIV-specific CD4 + T cell responses and decreased breadth of HIV-specific CD8 + T cell responses in vaccine recipients, independent of type-specific preexisting Ad5-specific neutralizing antibody titers. Further, epitopes recognized by adenovirus-specific T cells were commonly conserved across many adenovirus serotypes, suggesting that cross-reactivity of preexisting adenovirus-specific T cells can extend to adenovirus vectors derived from rare serotypes. These findings provide what we believe to be a new understanding of how preexisting viral immunity may impact the efficacy of vaccines under current evaluation for prevention of HIV, tuberculosis, and malaria.

Background-Abdominal aortic aneurysm (AAA) is a relatively common disease, with 1% to 2% of the population harboring aneurysms. Genetic risk factors are likely to contribute to the development of AAAs, although no such risk factors have been identified. Methods and Results-We performed a whole-genome scan of AAA using affected-relative-pair (ARP) linkage analysis that includes covariates to allow for genetic heterogeneity. We found strong evidence of linkage (logarithm of odds [LOD] scoreϭ4.64) to a region near marker D19S433 at 51.88 centimorgans (cM) on chromosome 19 with 36 families (75 ARPs) when including sex and the number of affected first-degree relatives of the proband (N aff ) as covariates. We then genotyped 83 additional families for the same markers and typed additional markers for all families and obtained a LOD score of 4.75 (Pϭ0.00014) with sex, N aff , and their interaction as covariates near marker D19S416 (58.69 cM).We also identified a region on chromosome 4 with a LOD score of 3.73 (Pϭ0.0012) near marker D4S1644 using the same covariate model as for chromosome 19. Conclusions-Our results provide evidence for genetic heterogeneity and the presence of susceptibility loci for AAA on chromosomes 19q13 and 4q31.

Abstract-We have shown that the G protein-coupled receptor (GPCR) agonists, thrombin and Factor Xa, stimulate smooth muscle cell (SMC) proliferation through transactivation of the EGF receptor (EGFR) or the FGF receptor (FGFR), both of which are tyrosine kinase receptors. In the present study, we investigated whether platelet-derived growth factor (PDGF), a tyrosine kinase receptor agonist, might transactivate another tyrosine kinase receptor to induce SMC proliferation. Because heparin inhibits PDGF-mediated proliferation in human SMCs, we investigated whether the heparin-binding growth factor basic fibroblast growth factor (bFGF) and one of its receptors, FGFR-1, play a role in the response of human arterial SMCs to PDGF-BB. PDGF-BB induced the release of bFGF and sustained phosphorylation of FGFR-1 (30 minutes to 6 hours). A bFGF-neutralizing antibody inhibited PDGF-BB-mediated phosphorylation of FGFR-1, DNA synthesis, and cell proliferation. In the presence of bFGF antibody, PDGF-BB-induced early activation of ERK (0 to 60 minutes) was not affected, whereas late ERK activation (2 to 4 hours) was reduced. When FGFR-1 expression was suppressed using small interfering RNA (siRNA), ERK activation was reduced at late, but not early, time points after PDGF-BB stimulation. Addition of bFGF antibody to cells treated with siRNA to FGFR-1 had no further effect on ERK activation. Our results provide support for a novel mechanism by which PDGF-BB induces the release of bFGF and activation of FGFR-1 followed by the sustained activation of ERK and proliferation of human SMCs.

We evaluated replication-defective poxvirus vectors (modified vaccinia Ankara [MVA] and fowlpox [FPV]) in a homologous and heterologous vector prime-boost vaccination regimen containing matching HIV inserts (MVA-HIV and FPV-HIV) given at months 0, 1, 3, 5 and 7 in 150 healthy HIV-negative vaccinia-naïve participants. FPV-HIV alone was poorly immunogenic, while the high dose (10 9 NIH Public Access Author ManuscriptVaccine. Author manuscript; available in PMC 2011 February 24.Published in final edited form as: Vaccine. 2011 February 24; 29(10): 1948-1958. doi:10.1016/j.vaccine.2010. NIH-PA Author ManuscriptNIH-PA Author Manuscript NIH-PA Author Manuscript boost. Thus, a heterologous poxvirus vector prime-boost regimen can induce an HIV-specific CD8+ T-cell and CD4+ T-cell responses, which may be an important feature of an optimal regimen for preventive HIV vaccination.

Drones are increasingly being used globally for the support of healthcare programmes. Madagascar, Malawi and Senegal are among a group of early adopters piloting the use of bi-directional transport drones for health systems in sub-Saharan Africa. This article presents the experiences as well as the strengths, weaknesses, opportunities and threats (SWOT analysis) of these country projects. Methods for addressing regulatory, feasibility, acceptability, and monitoring and evaluation issues are presented to guide future implementations. Main recommendations for governments, implementers, drone providers and funders include (1) developing more reliable technologies, (2) thorough vetting of drone providers’ capabilities during the selection process, (3) using and strengthening local capacity, (4) building in-country markets and businesses to maintain drone operations locally, (5) coordinating efforts among all stakeholders under government leadership, (6) implementing and identifying funding for long-term projects beyond pilots, and (7) evaluating impacts via standardised indicators. Sharing experiences and evidence from ongoing projects is needed to advance the use of drones for healthcare.