1
|
Pennington SH, Ferreira DM, Reiné J, Nyirenda TS, Thompson AL, Hancock CA, Wright AD, Gordon SB, Gordon MA. Longevity of duodenal and peripheral T-cell and humoral responses to live-attenuated Salmonella Typhi strain Ty21a. Vaccine 2018; 36:4725-4733. [PMID: 29958737 PMCID: PMC6041722 DOI: 10.1016/j.vaccine.2018.05.114] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2018] [Revised: 05/08/2018] [Accepted: 05/31/2018] [Indexed: 12/26/2022]
Abstract
BACKGROUND We have previously demonstrated that polyfunctional Ty21a-responsive CD4+ and CD8+ T cells are generated at the duodenal mucosa 18 days following vaccination with live-attenuated S. Typhi (Ty21a). The longevity of cellular responses has been assessed in peripheral blood, but persistence of duodenal responses is unknown. METHODS We vaccinated eight healthy adults with Ty21a. Peripheral blood and duodenal samples were acquired after a median of 1.5 years (ranging from 1.1 to 3.7 years) following vaccination. Cellular responses were assessed in peripheral blood and at the duodenal mucosa by flow cytometry. Levels of IgG and IgA were also assessed in peripheral blood by enzyme-linked immunosorbent assay. RESULTS No T-cell responses were observed at the duodenal mucosa, but CD4+ T-cell responses to Ty21a and FliC were observed in peripheral blood. Peripheral anti-lipopolysaccharide IgG and IgA responses were also observed. Early immunoglobulin responses were not associated with the persistence of long-term cellular immune responses. CONCLUSIONS Early T-cell responses which we have previously observed at the duodenal mucosa 18 days following oral vaccination with Ty21a could not be detected at a median of 1.5 years. Peripheral responses were observed at this time. Immunoglobulin responses observed shortly after vaccination were not associated with cellular immune responses at 1.5 years, suggesting that the persistence of cellular immunity is not associated with the strength of the initial humoral response to vaccination.
Collapse
Affiliation(s)
- Shaun H Pennington
- Department of Clinical Infection, Microbiology and Immunology, Institute of Infection and Global Health, University of Liverpool, UK; Department of Clinical Sciences, Liverpool School of Tropical Medicine, UK
| | - Daniela M Ferreira
- Department of Clinical Sciences, Liverpool School of Tropical Medicine, UK
| | - Jesús Reiné
- Department of Clinical Sciences, Liverpool School of Tropical Medicine, UK
| | - Tonney S Nyirenda
- Department of Clinical Sciences, Liverpool School of Tropical Medicine, UK; Malawi-Liverpool-Wellcome Trust Clinical Research Programme, College of Medicine, Queen Elizabeth Central Hospital, Malawi
| | - Ameeka L Thompson
- Department of Clinical Infection, Microbiology and Immunology, Institute of Infection and Global Health, University of Liverpool, UK; Department of Clinical Sciences, Liverpool School of Tropical Medicine, UK
| | - Carole A Hancock
- Department of Clinical Sciences, Liverpool School of Tropical Medicine, UK
| | - Angela D Wright
- Department of Clinical Sciences, Liverpool School of Tropical Medicine, UK
| | - Stephen B Gordon
- Department of Clinical Sciences, Liverpool School of Tropical Medicine, UK; Malawi-Liverpool-Wellcome Trust Clinical Research Programme, College of Medicine, Queen Elizabeth Central Hospital, Malawi
| | - Melita A Gordon
- Department of Clinical Infection, Microbiology and Immunology, Institute of Infection and Global Health, University of Liverpool, UK; Malawi-Liverpool-Wellcome Trust Clinical Research Programme, College of Medicine, Queen Elizabeth Central Hospital, Malawi.
| |
Collapse
|
2
|
Nyombayire J, Anzala O, Gazzard B, Karita E, Bergin P, Hayes P, Kopycinski J, Omosa-Manyonyi G, Jackson A, Bizimana J, Farah B, Sayeed E, Parks CL, Inoue M, Hironaka T, Hara H, Shu T, Matano T, Dally L, Barin B, Park H, Gilmour J, Lombardo A, Excler JL, Fast P, Laufer DS, Cox JH. First-in-Human Evaluation of the Safety and Immunogenicity of an Intranasally Administered Replication-Competent Sendai Virus-Vectored HIV Type 1 Gag Vaccine: Induction of Potent T-Cell or Antibody Responses in Prime-Boost Regimens. J Infect Dis 2016; 215:95-104. [PMID: 28077588 PMCID: PMC5225252 DOI: 10.1093/infdis/jiw500] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2016] [Accepted: 10/13/2016] [Indexed: 11/22/2022] Open
Abstract
Background. We report the first-in-human safety and immunogenicity assessment of a prototype intranasally administered, replication-competent Sendai virus (SeV)–vectored, human immunodeficiency virus type 1 (HIV-1) vaccine. Methods. Sixty-five HIV-1–uninfected adults in Kenya, Rwanda, and the United Kingdom were assigned to receive 1 of 4 prime-boost regimens (administered at 0 and 4 months, respectively; ratio of vaccine to placebo recipients, 12:4): priming with a lower-dose SeV-Gag given intranasally, followed by boosting with an adenovirus 35–vectored vaccine encoding HIV-1 Gag, reverse transcriptase, integrase, and Nef (Ad35-GRIN) given intramuscularly (SLA); priming with a higher-dose SeV-Gag given intranasally, followed by boosting with Ad35-GRIN given intramuscularly (SHA); priming with Ad35-GRIN given intramuscularly, followed by boosting with a higher-dose SeV-Gag given intranasally (ASH); and priming and boosting with a higher-dose SeV-Gag given intranasally (SHSH). Results. All vaccine regimens were well tolerated. Gag-specific IFN-γ enzyme-linked immunospot–determined response rates and geometric mean responses were higher (96% and 248 spot-forming units, respectively) in groups primed with SeV-Gag and boosted with Ad35-GRIN (SLA and SHA) than those after a single dose of Ad35-GRIN (56% and 54 spot-forming units, respectively) or SeV-Gag (55% and 59 spot-forming units, respectively); responses persisted for ≥8 months after completion of the prime-boost regimen. Functional CD8+ T-cell responses with greater breadth, magnitude, and frequency in a viral inhibition assay were also seen in the SLA and SHA groups after Ad35-GRIN boost, compared with those who received either vaccine alone. SeV-Gag did not boost T-cell counts in the ASH group. In contrast, the highest Gag-specific antibody titers were seen in the ASH group. Mucosal antibody responses were sporadic. Conclusions. SeV-Gag primed functional, durable HIV-specific T-cell responses and boosted antibody responses. The prime-boost sequence appears to determine which arm of the immune response is stimulated. Clinical Trials Registration. NCT01705990.
Collapse
Affiliation(s)
| | - Omu Anzala
- Kenya AIDS Vaccine Initiative Institute of Clinical Research, Nairobi
| | - Brian Gazzard
- Chelsea and Westminster Healthcare NHS Foundation Trust
| | | | - Philip Bergin
- Human Immunology Laboratory, International AIDS Vaccine Initiative, London, United Kingdom
| | - Peter Hayes
- Human Immunology Laboratory, International AIDS Vaccine Initiative, London, United Kingdom
| | - Jakub Kopycinski
- Human Immunology Laboratory, International AIDS Vaccine Initiative, London, United Kingdom
| | | | - Akil Jackson
- Chelsea and Westminster Healthcare NHS Foundation Trust
| | | | - Bashir Farah
- Kenya AIDS Vaccine Initiative Institute of Clinical Research, Nairobi
| | - Eddy Sayeed
- International AIDS Vaccine Initiative, New York, New York
| | | | | | | | | | | | - Tetsuro Matano
- University of Tokyo.,National Institute of Infectious Diseases, Tokyo, Japan
| | - Len Dally
- Emmes Corporation, Rockville, Maryland
| | | | - Harriet Park
- International AIDS Vaccine Initiative, New York, New York
| | - Jill Gilmour
- Human Immunology Laboratory, International AIDS Vaccine Initiative, London, United Kingdom
| | | | | | - Patricia Fast
- International AIDS Vaccine Initiative, New York, New York
| | - Dagna S Laufer
- International AIDS Vaccine Initiative, New York, New York
| | | | | |
Collapse
|
3
|
Pennington SH, Thompson AL, Wright AKA, Ferreira DM, Jambo KC, Wright AD, Faragher B, Gilmour JW, Gordon SB, Gordon MA. Oral Typhoid Vaccination With Live-Attenuated Salmonella Typhi Strain Ty21a Generates Ty21a-Responsive and Heterologous Influenza Virus-Responsive CD4+ and CD8+ T Cells at the Human Intestinal Mucosa. J Infect Dis 2016; 213:1809-19. [PMID: 26810369 PMCID: PMC4857474 DOI: 10.1093/infdis/jiw030] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2015] [Accepted: 01/06/2016] [Indexed: 01/15/2023] Open
Abstract
Background. Oral vaccination with live-attenuated Salmonella Typhi strain Ty21a is modestly efficacious, but the mechanisms of protection are currently unknown. While humoral and cellular immune responses are well described in peripheral blood, the cellular response at the intestinal mucosa has never been directly assessed. Methods. We vaccinated healthy adults with Ty21a and assessed humoral and cellular immunity in vaccinated volunteers and controls after 18 days. Immunoglobulin levels were assessed in peripheral blood by an enzyme-linked immunosorbent assay. Cellular responses were assessed in peripheral blood and at the duodenal and colonic mucosa by flow cytometry. Results. We demonstrate the generation of Ty21a-responsive and heterologous influenza virus–responsive CD4+ and CD8+ T cells at the duodenal mucosa. All duodenal responses were consistently correlated, and no responses were observed at the colonic mucosa. Peripheral anti-lipopolysaccharide immunoglobulin G and immunoglobulin A responses were significantly correlated with duodenal responses. The assessment of integrin β7 expression intensity among peripheral and duodenal T-cell subsets revealed varied capacities for mucosal homing and residence. Conclusions. The breadth of duodenal cellular responses was not reflected peripherally. The direct evaluation of mucosal immune defense may yield functional correlates of protection and could provide insight into mechanisms that may be manipulated to enhance vaccine immunogenicity.
Collapse
Affiliation(s)
- Shaun H Pennington
- Department of Clinical Infection, Microbiology, and Immunology, Institute of Infection and Global Health, University of Liverpool Department of Clinical Sciences, Liverpool School of Tropical Medicine
| | - Ameeka L Thompson
- Department of Clinical Infection, Microbiology, and Immunology, Institute of Infection and Global Health, University of Liverpool Department of Clinical Sciences, Liverpool School of Tropical Medicine
| | - Adam K A Wright
- Department of Clinical Sciences, Liverpool School of Tropical Medicine
| | | | - Kondwani C Jambo
- Department of Clinical Sciences, Liverpool School of Tropical Medicine
| | - Angela D Wright
- Department of Clinical Sciences, Liverpool School of Tropical Medicine
| | - Brian Faragher
- Department of Clinical Sciences, Liverpool School of Tropical Medicine
| | - Jill W Gilmour
- International AIDS Vaccine Initiative, Human Immunology Laboratory, Imperial College, London, United Kingdom
| | - Stephen B Gordon
- Department of Clinical Sciences, Liverpool School of Tropical Medicine
| | - Melita A Gordon
- Department of Clinical Infection, Microbiology, and Immunology, Institute of Infection and Global Health, University of Liverpool
| |
Collapse
|
4
|
Ma W, Wu G, Zheng H, Zhang W, Peng Z, Yu R, Wang N. Prevalence and risk factors of HIV and syphilis, and knowledge and risk behaviors related to HIV/AIDS among men who have sex with men in Chongqing, China. J Biomed Res 2015; 30:101-111. [PMID: 28276665 PMCID: PMC4820887 DOI: 10.7555/jbr.30.20150057] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2015] [Revised: 04/30/2015] [Accepted: 06/07/2015] [Indexed: 11/06/2022] Open
Abstract
High HIV prevalence and incidence burdens have been reported in men who have sex with men (MSM) in Chongqing, China. We aimed to estimate the prevalence of HIV and other sexually transmitted infections (STIs), to appraise the knowledge and risk behaviors related to HIV/AIDS among MSM, and to analyze the possible causes of deviation between behavior and knowledge to make better strategies. We recruited 617 MSM from February to July in 2008 by using a respondent-driven sampling (RDS) method in Chongqing, China. Through the collection of questionnaire-based data and biological testing results from all objects, we launched a cross-sectional survey. STATA/SE was used for data analysis by frequency, ANOVA, rank sum test and logistic regression models. MSM with syphilis (OR=4.16, 95%CI: 2.35-7.33, P<0.0001) were more likely to be HIV infected. Being a company employee (OR=3.64, 95%CI: 1.22-10.08, P<0.0001) and having bought male for sex (OR=3.52, 95%CI: 1.10-11.32, P < 0.034) were associated with a higher probability of syphilis. MSM with younger age, higher education and greater monthly income had a higher mean knowledge score. MSM who had HIV testing had a higher mean knowledge score than those who never had. Students, venues for finding sex partners by Internet and homosexuals in MSM had a higher mean knowledge score compared to other occupations, venues for finding sex partners and sexual orientation. There is an urgent need for delivery of barrier and biomedical interventions with coordinated behavioral and structural strategies to improve the effect of HIV interventions among MSM.
Collapse
Affiliation(s)
- Wenzhe Ma
- Department of Epidemiology and Biostatistics, School of Public Health, Nanjing Medical University, Nanjing, Jiangsu 211166, China
| | - Gohui Wu
- Chongqing Center for Disease Control and Prevention, Chongqing, China
| | - Hui Zheng
- Department of Epidemiology and Biostatistics, School of Public Health, Nanjing Medical University, Nanjing, Jiangsu 211166, China
| | - Wenjuan Zhang
- Department of Epidemiology and Biostatistics, School of Public Health, Nanjing Medical University, Nanjing, Jiangsu 211166, China
| | - Zhihang Peng
- Department of Epidemiology and Biostatistics, School of Public Health, Nanjing Medical University, Nanjing, Jiangsu 211166, China;
| | - Rongbin Yu
- Department of Epidemiology and Biostatistics, School of Public Health, Nanjing Medical University, Nanjing, Jiangsu 211166, China;
| | - Ning Wang
- National Center for AIDS/STD Control and Prevention, Chinese Center for Disease Control and Prevention, Beijing, China
| |
Collapse
|
5
|
CD8+/CD161++ mucosal-associated invariant T-cell levels in the colon are restored on long-term antiretroviral therapy and correlate with CD8+ T-cell immune activation. AIDS 2014; 28:1690-2. [PMID: 24911351 DOI: 10.1097/qad.0000000000000351] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
Mucosal-associated invariant T (MAIT) cells are tissue-homing T cells recently implicated in HIV pathogenesis. We found that the proportion of MAIT cell in blood and colon of HIV+ patients are reduced in untreated infection. Antiretroviral therapy restored colonic but not blood MAIT cell percentages. We observed a negative correlation between colonic MAIT cells and T-cell activation in blood and suggest mucosal MAIT cell depletion may contribute to systemic immune activation in HIV infection.
Collapse
|
6
|
Finak G, Jiang W, Krouse K, Wei C, Sanz I, Phippard D, Asare A, De Rosa SC, Self S, Gottardo R. High-throughput flow cytometry data normalization for clinical trials. Cytometry A 2013; 85:277-86. [PMID: 24382714 DOI: 10.1002/cyto.a.22433] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2013] [Revised: 11/18/2013] [Accepted: 12/13/2013] [Indexed: 01/08/2023]
Abstract
Flow cytometry datasets from clinical trials generate very large datasets and are usually highly standardized, focusing on endpoints that are well defined apriori. Staining variability of individual makers is not uncommon and complicates manual gating, requiring the analyst to adapt gates for each sample, which is unwieldy for large datasets. It can lead to unreliable measurements, especially if a template-gating approach is used without further correction to the gates. In this article, a computational framework is presented for normalizing the fluorescence intensity of multiple markers in specific cell populations across samples that is suitable for high-throughput processing of large clinical trial datasets. Previous approaches to normalization have been global and applied to all cells or data with debris removed. They provided no mechanism to handle specific cell subsets. This approach integrates tightly with the gating process so that normalization is performed during gating and is local to the specific cell subsets exhibiting variability. This improves peak alignment and the performance of the algorithm. The performance of this algorithm is demonstrated on two clinical trial datasets from the HIV Vaccine Trials Network (HVTN) and the Immune Tolerance Network (ITN). In the ITN data set we show that local normalization combined with template gating can account for sample-to-sample variability as effectively as manual gating. In the HVTN dataset, it is shown that local normalization mitigates false-positive vaccine response calls in an intracellular cytokine staining assay. In both datasets, local normalization performs better than global normalization. The normalization framework allows the use of template gates even in the presence of sample-to-sample staining variability, mitigates the subjectivity and bias of manual gating, and decreases the time necessary to analyze large datasets.
Collapse
Affiliation(s)
- Greg Finak
- Vaccine and Infectious Disease Division, Fred Hutchinson Cancer Research Center, Seattle, Washington, 98109
| | | | | | | | | | | | | | | | | | | |
Collapse
|
7
|
Beyrer C, Baral SD, van Griensven F, Goodreau SM, Chariyalertsak S, Wirtz AL, Brookmeyer R. Global epidemiology of HIV infection in men who have sex with men. Lancet 2012; 380:367-77. [PMID: 22819660 PMCID: PMC3805037 DOI: 10.1016/s0140-6736(12)60821-6] [Citation(s) in RCA: 1133] [Impact Index Per Article: 94.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
Epidemics of HIV in men who have sex with men (MSM) continue to expand in most countries. We sought to understand the epidemiological drivers of the global epidemic in MSM and why it continues unabated. We did a comprehensive review of available data for HIV prevalence, incidence, risk factors, and the molecular epidemiology of HIV in MSM from 2007 to 2011, and modelled the dynamics of HIV transmission with an agent-based simulation. Our findings show that the high probability of transmission per act through receptive anal intercourse has a central role in explaining the disproportionate disease burden in MSM. HIV can be transmitted through large MSM networks at great speed. Molecular epidemiological data show substantial clustering of HIV infections in MSM networks, and higher rates of dual-variant and multiple-variant HIV infection in MSM than in heterosexual people in the same populations. Prevention strategies that lower biological transmission and acquisition risks, such as approaches based on antiretrovirals, offer promise for controlling the expanding epidemic in MSM, but their potential effectiveness is limited by structural factors that contribute to low health-seeking behaviours in populations of MSM in many parts of the world.
Collapse
Affiliation(s)
- Chris Beyrer
- Center for Public Health and Human Rights, Johns Hopkins Bloomberg School of Public Health, Baltimore, MD 21205, USA.
| | | | | | | | | | | | | |
Collapse
|
8
|
Andersen-Nissen E, Heit A, McElrath MJ. Profiling immunity to HIV vaccines with systems biology. Curr Opin HIV AIDS 2012; 7:32-7. [PMID: 22134340 DOI: 10.1097/coh.0b013e32834ddcd9] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
PURPOSE OF REVIEW The recent modest success of the RV144 HIV vaccine trial in Thailand has shown that development of an HIV vaccine is possible. Designing a vaccine that achieves better protection, however, will require a more complete understanding of vaccine mechanisms of action and correlates of protection. Systems biology approaches enable integration of large datasets from a variety of assays and offer new approaches to understanding how vaccine-induced immune responses are coordinately regulated. In this review, we discuss the recent advances in clinical trial design, specimen collection, and assay standardization that will generate datasets for systems analyses of immune responses to HIV vaccines. RECENT FINDINGS Several recently published HIV vaccine trials have shown that different HIV vaccine prime/boost combinations can greatly affect the immune response generated, but mechanistic insights into their modes of action are lacking. Novel systems biology studies of efficacious, licensed vaccines provide a new template for analysis of HIV vaccines. To generate datasets appropriate for systems analysis, current HIV vaccine clinical trials are undergoing design modifications and increased standardization of specimen collection and immune response assays. SUMMARY Systems biology approaches to HIV vaccine evaluation are driving new methods of HIV vaccine immune response profiling in clinical trials and will hopefully lead to new improved HIV vaccines in the near future.
Collapse
Affiliation(s)
- Erica Andersen-Nissen
- Vaccine and Infectious Disease Division, Fred Hutchinson Cancer Research Center, Seattle, Washington, USA
| | | | | |
Collapse
|
9
|
De Rosa SC. Vaccine applications of flow cytometry. Methods 2012; 57:383-91. [PMID: 22251671 DOI: 10.1016/j.ymeth.2012.01.001] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2011] [Revised: 12/16/2011] [Accepted: 01/03/2012] [Indexed: 10/14/2022] Open
Abstract
Highly effective vaccines have yet to be identified for many widespread infectious diseases including HIV, tuberculosis and malaria. Many vaccine candidates for these diseases have been designed to induce both cellular and humoral immunity, and measurement of the induced cellular immune response and antibody response is critical for monitoring immunogenicity. The flow cytometric intracellular cytokine staining assay is one of the primary assays for enumerating vaccine-induced T cells in vaccine clinical trials. The assay is flexible, allowing for measurement of various cytokines or functions and phenotyping markers, and the assay can be validated. Changes in other cell types such as innate immune cells are monitored by flow cytometric phenotyping assays. Cell sorting of vaccine-induced T cells and B cells is used to allow genomic and transcriptional analysis of these cells. Thus, flow cytometric methods are commonly used in trials testing the next generation of vaccines.
Collapse
Affiliation(s)
- Stephen C De Rosa
- Department of Laboratory Medicine, University of Washington, Seattle, WA 98195, USA.
| |
Collapse
|
10
|
Hopkins R, Bridgeman A, Bourne C, Mbewe-Mvula A, Sadoff JC, Both GW, Joseph J, Fulkerson J, Hanke T. Optimizing HIV-1-specific CD8+ T-cell induction by recombinant BCG in prime-boost regimens with heterologous viral vectors. Eur J Immunol 2011; 41:3542-52. [PMID: 21932450 DOI: 10.1002/eji.201141962] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2011] [Revised: 08/18/2011] [Accepted: 09/12/2011] [Indexed: 11/07/2022]
Abstract
The desire to induce HIV-1-specific responses soon after birth to prevent breast milk transmission of HIV-1 led us to propose a vaccine regimen which primes HIV-1-specific T cells using a recombinant Mycobacterium bovis bacillus Calmette-Guérin (rBCG) vaccine. Because attenuated live bacterial vaccines are typically not sufficiently immunogenic as stand-alone vaccines, rBCG-primed T cells will likely require boost immunization(s). Here, we compared modified Danish (AERAS-401) and Pasteur lysine auxotroph (222) strains of BCG expressing the immunogen HIVA for their potency to prime HIV-1-specific responses in adult BALB/c mice and examined four heterologous boosting HIVA vaccines for their immunogenic synergy. We found that both BCG.HIVA(401) and BCG.HIVA(222) primed HIV-1-specific CD8(+) T-cell-mediated responses. The strongest boosts were delivered by human adenovirus-vectored HAdV5.HIVA and sheep atadenovirus-vectored OAdV7.HIVA vaccines, followed by poxvirus MVA.HIVA; the weakest was plasmid pTH.HIVA DNA. The prime-boost regimens induced T cells capable of efficient in vivo killing of sensitized target cells. We also observed that the BCG.HIVA(401) and BCG.HIVA(222) vaccines have broadly similar immunologic properties, but display a number of differences mainly detected through distinct profiles of soluble intercellular signaling molecules produced by immune splenocytes in response to both HIV-1- and BCG-specific stimuli. These results encourage further development of the rBCG prime-boost regimen.
Collapse
Affiliation(s)
- Richard Hopkins
- MRC Human Immunology Unit, Weatherall Institute of Molecular Medicine, University of Oxford, Oxford, UK
| | | | | | | | | | | | | | | | | |
Collapse
|