Telmisartan (TMS) is an angiotensin receptor blocker with anti-inflammatory properties and little or no clinical immunosuppressive effect. We undertook an unblinded, single arm, pilot study of TMS (160 mg/d p.o.) for prevention of acute graft vs. host disease (aGvHD) in recipients of HLA matched allogeneic hematopoietic stem cell transplants (HSCTs). Primary endpoints of Grade II or >Grade III aGvHD (1994 Consensus Conference on Acute GVHD Grading) were compared with 178 similar HSCT historical controls over the preceding 3 yrs at our institution: 26% >Grade III, 74% Grade II. Safety endpoints included engraftment, relapse/progression by day (d) 180, non-relapse mortality by d 180, and serious drug-related adverse reactions. Experimental data were collected on blood endotoxin levels and stool microbiome composition. The study was powered to detect 20% or 50% reduced rates of, respectively, Grade II or >Grade III. We report results from a planned interim analysis triggered when the first 22 evaluable patients (pts) reached d 100. Of 27 evaluable pts, 24 were beyond d 180 by completion of this interim analysis. The study was designed to treat pts for two days prior to, and day of HSCT, and for an additional 98 days post-transplant, but pts were considered evaluable if they completed >14 days of post- transplant TMS, including pre-determined dose reductions. One enrollee received TMS for 13 days post-HSCT and was excluded from analysis. Five pts received 14-24 days of drug (4 by choice, 1 died of sepsis). More than half the evaluable patients (17/27) completed >94 days of post-HSCT therapy, including 6 who experienced an episode of hypotension. Almost half (13/27) received >80% of the full 101 day dose (16,160 mg), including 5 who experienced hypotension. Of the 6 enrollees receiving <24 days of drug, two had documented hypotension. No other serious drug-attributed adverse reactions were reported. Reasons cited for pts choosing to discontinue TMS were inconvenience of taking pills, and home stool sampling. Safety Endpoints: All pts engrafted promptly (ANC >500/uL, platelet >20,000/uL). Peripheral donor CD3+ T cell median and range of chimerism on days 28 and 84 were 99.5% (37-100) and 100.0% (36-100); bone marrow donor CD34+ cell chimerism was 97.0% (62-100). There was a single NRM during the 180 d study, and no graft rejection or increase in relapse or progression. Four relapses occurred within 180 days, and 2 more after d 180, resulting in two relapse deaths (d 370, and d 600). Primary Endpoints:A single individual developed hyperacute Grade III skin GvHD on day 7 p-HSCT. Another 12 of 27 patients developed Grade 2 aGvHD, one after the conventional 100 d window (d 141). Compared with historical controls, the incidence of aGvHD was significantly reduced for Grade II (p < 0.005) and Grade >III (p = 0.01), using the two-tailed Z-test of proportions. Experimental Endpoints: Acute GvHD is associated with increased gut permeability, bacterial translocation, and loss of gut microbiome diversity. Endotoxemia, an indicator of intestinal integrity, as measured by the endotoxin activity assay (EAA, Spectral Medical) reached septic levels in 40% of patients during pre-transplant conditioning (d -3 - d 0), and subsequently returned to, or maintained, non-septic levels from week 5 onward in 90% of patients, with an overall downward group trend of EAA scores during 180 days of follow up. Genotyping and analysis of bacterial V4 16S ribosomal DNA from weekly stool samples of the first 10 evaluable patients revealed no decrease in OTU richness or Shannon diversity at any time point pre- vs. post- treatment. Among the 5 most abundant phyla, Bacteroidetes was significantly less abundant post-treatment compared to pre-treatment. Among the 8 most abundant families, Bacteroidaceae significantly decreased post- vs. pre- treatment. While historic microbiome controls from our institution are not available, our finding of increased Bacteroidetes is in contrast to reported decreased Bacteroidetes in allogeneic HSCTs not receiving TMS, but may resemble changes after autologous HSCT. This trial, funded by the Gateway Foundation, is ongoing. Preliminary results indicate TMS is well tolerated, with a beneficial impact on aGvHD and no increased relapse or NRM, with excellent engraftment, and preservation of anti-tumor effect, intestinal barrier integrity, and gut microbial diversity. Disclosures Iyengar: Hackensack University Medical Center: Patents & Royalties: Telmisartan use patent.. Rowley:Allergan: Equity Ownership; Fate Therapeutics: Consultancy. Schwartz:Hackensack University Medical Center: Patents & Royalties: Telmisartan use patent. OffLabel Disclosure: Telmisartan. Indicated for treatment of hypertension.
Although scholars are beginning to examine the experience of crowdsourced work, the extant literature and popular accounts paint an undersocialized picture of the labor process. This study explores how crowdsourced work remains socially embedded in the structure of an occupational community that exists exclusively online and in relation to a focal firm. The findings draw on interviews and observation of creative freelancers who designed, developed, and distributed digital goods in a crowdsourced work arrangement with an entertainment publisher. The online meeting places of an occupational community supported workers in their responses to three challenges of contingency: limited communication with the firm, sporadic and unpredictable compensation for their work, and unclear career trajectory. Within the community, freelancers found direction and meaning for their work, built collective strategies to smooth compensation, and illuminated a pathway from amateur to expert. As an occupational institution, the community also structured collaborations that transferred knowledge of industry standard practice and coordinated work in the absence of bureaucratic organization.
Background: Telmisartan (TMS) is an angiotensin receptor blocker (ARB), approved in 1998 for treatment of hypertension. Additional mechanisms of action were described post-approval, including PPARγ agonism (by physical binding) and Rho Kinase inhibition (indirectly, at the level of gene expression). A third function is suppression of NADPH oxidase, causing increased Nrf2, a master regulator of anti-oxidant genes like superoxide dismutase. TMS’s effect on blood pressure plateaus at 80 - 160 mg/day, and is minimal in normotensive subjects. Elimination of intact bioactive drug is via intestine and biliary tract, without liver enzyme involvement.
Acute graft-versus-host disease (GVHD) is a major complication of allogeneic hematopoietic cell transplantation (HCT) and the main cause of nonrelapse mortality during the first 100 days post-transplant. Although GVHD can be prevented by extensive removal of mature donor T cells from the donor hematopoietic stem cell population, doing so eliminates any potential allogeneic graft-versus-tumor (GVT) effect also mediated by donor T cells and results in unacceptable rates of cancer relapse. One potential solution to this problem of separating GVHD development from a GVT response is to prevent T cell mediated GVHD in the intestinal tract (IT) while preserving systemic antihost alloreactivity of donor T cells that target residual tumor cells expressing host alloantigens. We examined the ability of the anti-inflammatory rho kinase inhibitor, fasudil, given orally and intraperitoneally, to prevent GVHD in a C3H -> B6C3F1 mouse model of MHC-haploidentical bone marrow transplantation. Fasudil-treated recipients of anti-thy-1 mAb + C' treated bone marrow (ATBM) cells plus T cells had a 73% 90-day survival compared with 25% among untreated ATBM + T cell recipients (P < .0001). Severe initial weight loss was similar in the 2 groups, but less diarrhea was observed among treated animals, and fasudil-treated survivors recovered more weight than untreated survivors. Skin inflammation occurred and resolved between weeks 2 and 8 with similar severity and kinetics in both treated and untreated surviving animals, indicating persistent alloreactivity. Day 10 post-transplantation splenocytes from fasudil-treated mice, containing mature donor T cells, and day 98 splenocytes, containing mature donor and de novo thymus-derived T cells, exhibited alloreactivity against host parental antigens, as assessed by in vitro IFN-gamma production and rounds of allostimulated proliferation, respectively. These data support the idea that targeted treatment of the IT with rho kinase inhibitors can ameliorate lethal GVHD while preserving systemic alloreactivity. The results also suggest that similar mechanisms of IT-specific tolerance or resistance to GVHD operate in fasudil-treated and untreated long-term survivors of allogeneic ATBM + T cells. (C) 2014 American Society for Blood and Marrow Transplantation.
Chemokine receptors (CKRs), the primordial receptors for primate lentiviruses, are sufficient to mediate virus-cell fusion. Several different fusogenic CKRs and related receptors provide a broad potential host cell range, presumably advantageous for viral spread within a given infected individual, and across species. By contrast, the additional constraint of obligatory CD4 binding, just prior to CKR engagement, radically restricts potential host cells within an individual (or lymph node microenvironment), and might also limit xenotransmission, as CD4 sequences vary among primates. In spite of these potential drawbacks, CD4 dependent entry for SIV and HIV is the rule rather than the exception, and is generally thought to have evolved by selection for 1) stabilization of virus–cell surface interactions, and 2) conformational shielding of readily neutralized CKR binding epitopes. CD4 binding residues of SIV and HIV envelope are recessed, (relatively hidden from immune detection) and may exhibit a strong degree of automimicry, thus benefitting from self tolerance.
R5 and X4 HIV strains use CCR5 or CXCR4 chemokine receptors (CKRs), respectively, for entry. Preferential growth of X4 vs. R5 HIV in cell lines reflects constitutive expression of CXCR4, but not CCR5 (in contrast to dual expression on primary T cells), and CXCR4 is the predominant CKR found on most tumors. Non-Hodgkin's B cell lymphomas (NHL) are increased among HIV(+) patients, and interactions between HIV envelope and CKRs may contribute to lymphomagenesis. Despite strong evidence for a CXCR4-SDF-1 oncogenic axis, no in vitro evaluation of CXCR4-mediated normal lymphocyte transformation has been published. Exposure of normal B cells to EBV in the presence of X4 gp120 (but not R5 gp120) increased proliferation and BLCL outgrowth, comparable to anti-CD40 mAb costimulation. This suggests a role for X4 tropic viral envelope signaling via CXCR4 and/or CXCR7 in HIV-associated lymphomagenesis.
Background. Since the primary routes of human immunodeficiency type 1 (HIV-1) infection are across mucosal barriers, a randomized trial of canarypox virus-based vectors was conducted in 84 individuals, with delivery of vaccine by mucosal routes, and was accompanied by a detailed analysis of humoral, cellular, and mucosal immune responses. Methods. Over the course of 6 months, HIV-1-specific (vCP 205) and rabies (vCP 65) canarypox virus vectors were delivered systemically and/or mucosally into the nose, mouth, vagina, or rectum in a 4-dose schedule, followed by 2 doses of HIV-1 MN recombinant glycoprotein (rgp) 120 or subunit rabies vaccine administered by the intramuscular route. Results. Administration of vaccine and collection of samples were well tolerated. Serum IgG HIV-1-specific antibodies to rgp120 were rarely seen after either systemic or mucosal delivery of canarypox virus vaccine. In contrast, serum IgG rabies and canarypox antibodies were detected in all individuals after systemic, but rarely after mucosal, delivery of vaccine. Suggestions of mucosal recognition of HIV-1 antigen included a cytotoxic T lymphocyte response in 4 of 8 individuals after administration of vaccine by the intrarectal route and a limited immunoglobulin A response at the same site. Conclusions. Each of the routes of vaccine administration was feasible in the context of a phase 1 study with motivated individuals. However, with the doses and routes of administration used, canarypox virus was not an effective mucosal immunogen.
Purpose: To evaluate the clinical significance of differences in 2-deoxy-2-[18F]fluoro-D-glucose positron emission tomography (FDG-PET) lymph node standardized uptake values (SUV) in human immunodeficiency virus (HIV) infection using iterative reconstruction with segmented attenuation correction (IR SAC) compared to filtered back-projection with measured attenuation correction (FBP MAC).
Thirty-three HIV-seronegative adults were recruited into a Phase I safety and immunogenicity HIV-1 vaccine trial. The immunogens were as follows: a synthetic, monovalent, octameric HIV-1 MN V3 peptide in aluminum hydroxide (alum) adjuvant administered by intramuscular delivery; and a similar product encapsulated in biodegradable micro-spheres composed of co-polymers of lactic and glycolic acids, administered by the oral route. These were administered in three sequential oral doses, followed by a parenteral boost. No serious adverse experiences were observed. Oral administration of this vaccine, alone or in combination with parenteral boosting, resulted in no significant humoral, cellular, or mucosal immune responses.
Three separate studies were undertaken in HIV-1 uninfected persons to determine if the adjuvant QS-21 improves the magnitude or kinetics of immune responses induced by recombinant soluble gp120 HIV-1MN protein (rsgp120) immunization. The QS-21 was administered at two doses (50 and 100 μg), either alone or in combination with aluminum hydroxide (600 μg). At the highest doses of rsgp120 (100, 300, and 600 μg), QS-21 exerted no significant effect on either binding or neutralizing antibody titers. Antibody binding and neutralizing responses fell dramatically when rsgp120, formulated with alum alone, was given at low doses (3 and 30 μg). In contrast, antibody responses similar in titer to those in the high dose antigen groups were induced with the low dose rsgp120 formulated with QS-21. In addition, the lymphocyte proliferation and delayed type hypersensitivity skin testing were superior in the QS-21 recipients compared with the alum recipients at the low antigen doses. Moderate to severe pain was observed in majority of the volunteers receiving QS-21 formulations, and vasovagal episodes and hypertension were not infrequent. Thus, the use of QS-21 may provide a means to reduce the dose of a soluble protein immunogen.
CD8+ cytolytic activity is traditionally measured by detecting the release of 51Cr after incubation of effector cells with HLA-matched, infected, radiolabeled targets. An alternative method to detect CD8+ activity is to measure the production of intracellular interferon gamma (IFNγ) after antigen-specific stimulation, either by ELISPOT or by flow cytometry. Studies were performed in 19 volunteers enrolled in a phase 1 trial of candidate canarypox HIV-1 vaccines that encoded multiple HIV-1 genes. The vaccines including vCP205 (Env, Gag, and protease), vCP1433 (Env, Gag, protease, and CTL epitope-rich regions of pol and nef) and vCP1452 (equivalent to vCP1433 with additional immunomodulatory genes of vaccinia). PBMCs were stimulated in vitro with vaccinia constructs encoding env and gag or a lacZ control, and the effectors were cultured for 12–14 days. EBV-transformed B cell lines were infected overnight with the vaccinia vectors, and then incubated with the effector cells for 4 h in the presence of monensin. CD8+ gene-specific activity was determined as a percentage of IFNγ cells in the CD3+CD8+CD45RO+ gate after subtracting both the isotype control and the lacZ control stimulation. CD4 memory IFNγ production was simultaneously determined in the CD3+CD8−CD45RO+ gate. Using these techniques in blinded studies, we found that CD8+ IFNγ activity could be measured in the majority of volunteers given four immunizations. Specifically, the responses to the gag gene were control — 0/2; vCP205 — 2/4; vCP1433 — 5/6; vCP1452 — 4/7. Most of the positive responses were detected after the fourth immunization. Flow cytometric techniques hold promise as a surrogate measure of CTL and for ease of phenotyping of the effector population.
Several immunogens induce HIV-specific neutralization and in vitro lymphoproliferation in adults at low HIV-1 risk, but responses in persons at high HIV-1 risk are not known. We performed a multicenter, double-blinded, adjuvant-controlled trial with two gp120 vaccines in 296 HIV-1-uninfected volunteers, including 176 reporting higher HIV-1 risk activities. The immunogens were remarkably well tolerated. After three immunizations, 210 of 241 vaccinees (87%) developed neutralizing antibodies, which persisted in 59% after 2 years. The injection drug users receiving SF-2/gp120 had decreased antibody responses relative to the lower risk groups. Envelope-specific lymphoproliferation peaked after two immunizations, and 54% of vaccinees mounted a DTH reaction to gp120 after 4 years. In summary, these immunogens have low adverse reactogenicity and induce durable antibody and T cell responses to the prototype strains. Unexpected differences in antibody responses among diverse HIV-1 risk strata lend support to the conduct of expanded phase II trials in populations other than low-risk volunteers.
A unique cohort of HIV-1-infected long term nonprogressors (LTNP) with normal CD4(+) T cell counts and <50 copies/ml of plasma were prospectively recruited for study. HLA typing revealed a dramatic association between the HLA B*5701 class I allele and nonprogressive infection [85% (11 of 13) vs. 9.5% (19 of 200) in progressors; P < 0. 001]. Antigen-specific CD8(+) T cells were enumerated by flow cytometric detection of intracellular IFN-gamma in response to HIV antigens and HLA B*57-gag tetramer staining. No quantitative differences in the total HIV-specific CD8(+) T cell responses were observed between B*57(+) LTNP and five B*57(+) progressors (P = 0.4). Although similar frequencies of peptide specific CD8(+) T cells were also found, the gag-specific CD8(+) T cell response in the LTNP group was highly focused on peptides previously shown to be B*57-restricted. These findings indicate that, within this phenotypically and genotypically distinct cohort, a host immune factor is highly associated with restriction of virus replication and nonprogressive disease. They also strongly suggest a mechanism of virus specific immunity that directly operates through the B*5701 molecule. Further characterization of qualitative differences in the virus-specific responses that distinguish HLA B*57(+) LTNP from progressors may ultimately define mechanisms of effective immune mediated restriction of virus replication.
A prospective study of high-risk commercial sex workers in Senegal has shown that HIV-2 infection may reduce the risk of subsequent HIV-1 infection; these findings have been confirmed and extended, now with 13 years of observation. While exploring the biological mechanisms behind this natural protection, we found that a significant proportion of peripheral blood mononuclear cells obtained from HIV-2-infected subjects resisted in vitro challenge with CCR5-dependent HIV-1 viruses but not CXCR4-dependent viruses. High levels of beta-chemokines, the natural ligands of the CCR5 coreceptor, were correlated with low levels of viral replication, and resistance was abrogated by antibodies to beta-chemokines. Our results suggest that beta-chemokine-mediated resistance may be an important correlate of HIV protection against HIV-1 infection and relevant to HIV vaccine design.
A safety and immunogenicity trial was conducted in vaccinia-immune and vaccinia-naive human immunodeficiency virus (HIV)-uninfected adults who were randomized to receive 10(6) or 10(7) TCID50 of canarypox (ALVAC) vector expressing HIV-1(MN) gp160 or 10(5.5) TCID50 of ALVAC-rabies virus glycoprotein control at 0 and 1 or 2 months and ALVAC-gp160 or 50 mu g of HIV-1(SF2) recombinant (r) gp12O in microfluidized emulsion at 9 and 12 months; others received rgp120 at 0, 1, 6, and 12 months. All vaccines were well-tolerated. Neither vaccinia-immune status before vaccination nor ALVAC dose affected HIV immune responses. HIV-1(MN) and HIV-1(SF2) neutralizing antibodies were detected more often (100%) in ALVAC-gp160/rgp120 recipients than in recipients of ALVAC-gp160 (<65%) or rgp120 (89%) alone. ALVAC-gp160/rgp120 also elicited more frequent HIV V3-specific and fusion-inhibition antibodies, antibody-dependent cellular cytotoxicity, lymphoproliferation, and cytotoxic CD8(+) T cell activity than did either vaccine alone. Trials with ALVAC expressing additional HIV components and rgp120 are underway.
Effective human immunodeficiency virus (HIV) vaccination may require induction of neutralizing antibodies (NAs) and CD8+ cytotoxic T lymphocytes (CTL) to prevent transmission and control early infection. Recombinant envelope proteins induce NAs but rarely CD8+ CTL responses, and vaccinia vectors containing HIV-1 envelope elicit CD8+ cytotoxicity but few NAs. To benefit from both approaches, 56 vaccinia-naive subjects were randomized to a regimen of priming with recombinant vaccinia gp160LAI and boosting with recombinant gp120SF-2, gp120LAI, gp120MN, or gp160MN. Of 51 persons for whom assays were done, 26 demonstrated envelope-specific CTL. Boosting with gp120, compared with gp160, elicited significantly more NAs and CD4-blocking antibodies. Neutralization of the homologous and heterologous HIV-1 laboratory strains occurred in all subjects receiving vac/env and gp120 and was detectable in 91% of the subjects for >6 months. Thus, vaccine regimens in which one component elicits primarily CTL and the other NAs offer promise for the development of an effective HIV-1 vaccine strategy.
Evolutionary patterns of virus replication and distribution in lymphoid tissue during the early phases of HIV infection have not been delineated. Lymph node (LN) biopsies were excised from patients at different times after the estimated time of primary infection. Within 3 months of the acute viral syndrome, HIV was mostly present in individual virus-expressing cells in LNs; trapping of virions in the follicular dendritic cell (FDC) network was minimal or absent, but was the predominant form of HIV detected in LNs of subjects with chronic infection, either recent (4–20 months after primary infection) or long-term (>2–3 years after primary infection). Plasma viremia was significantly higher in patients during the first 3 months than in those recently infected; however, there were no significant differences in the number of virus-expressing cells per square millimeter of LN tissue in these two groups. Numbers of virus-expressing cells in lymphoid tissue were significantly lower in the subjects with long-term infection than in the other two groups. Therefore, during the transition from primary to chronic HIV infection, the level of HIV replication in lymphoid tissue remains elevated despite the fact that viremia is significantly downregulated. These findings have implications for therapeutic strategies in primary HIV infection and in recent seroconvertors.
Among 2099 uninfected subjects in phase I and II trials of candidate AIDS vaccines, 23 were diagnosed with intercurrent human immunodeficiency virus type 1 (HIV-1) infection, High-risk sexual exposures accounted for 17 infections, and intravenous drug use accounted for 6, Four subjects received placebo, 13 received a complete immunization schedule (greater than or equal to 3 injections), and 6 were partially immunized (less than or equal to 2 injections), There was no significant difference between vaccine recipients and control groups in incidence of HIV-1 infection, virus load, CD4 lymphocyte count, or V3 loop amino acid sequence, In summary, 19 vaccinated subjects acquired HIV 1 infection during phase I and II trials, indicating that immunization with the products described is < 100% effective in preventing or rapidly clearing infection, Laboratory analysis suggested that vaccine-induced immune responses did not significantly affect the genotypic or phenotypic characteristics of transmitted virus or the early clinical course of HIV-1 infection.