Publications by authors named "Alistair Ramsay"

The COVID-19 pandemic reminded us of the urgent need for new antivirals to control emerging infectious diseases and potential future pandemics. Immunotherapy has revolutionized oncology and could complement the use of antivirals, but its application to infectious diseases remains largely unexplored. Nucleoside analogs are a class of agents widely used as antiviral and anti-neoplastic drugs.

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SARS-CoV-2 mRNA vaccines are administered as effective prophylactic measures for reducing virus transmission rates and disease severity. To enhance the durability of post-vaccination immunity and combat SARS-CoV-2 variants, boosters have been administered to two-dose vaccinees. However, long-term humoral responses following booster vaccination are not well characterized.

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Article Synopsis
  • The COVID-19 pandemic, caused by SARS-CoV-2, significantly affected healthcare, the workforce, and global economies, highlighting the need for effective vaccinations.
  • Multi-dose mRNA vaccines, like the Pfizer/BioNTech BNT162b2, have proven effective against SARS-CoV-2 and its variants, with a focus on neutralizing antibodies targeting the virus's receptor-binding domain (RBD).
  • A longitudinal study involving nine uninfected individuals showed that two doses of the mRNA vaccine produced strong humoral antibody responses across the entire spike protein, revealing new non-RBD epitopes that could enhance future vaccine and drug development.
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Sensitive and specific blood-based assays for the detection of pulmonary and extrapulmonary tuberculosis would reduce mortality associated with missed diagnoses, particularly in children. Here we report a nanoparticle-enhanced immunoassay read by dark-field microscopy that detects two Mycobacterium tuberculosis virulence factors (the glycolipid lipoarabinomannan and its carrier protein) on the surface of circulating extracellular vesicles. In a cohort study of 147 hospitalized and severely immunosuppressed children living with HIV, the assay detected 58 of the 78 (74%) cases of paediatric tuberculosis, 48 of the 66 (73%) cases that were missed by microbiological assays, and 8 out of 10 (80%) cases undiagnosed during the study.

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Bacille-Calmette-Guerin (BCG) has variable efficacy as an adult tuberculosis (TB) vaccine but can reduce the incidence and severity of TB infection in humans. We have engineered modified vaccinia Ankara (MVA) strain vaccine constructs to express the secreted mycobacterial proteins Ag85A and ESAT-6 (MVA-AE) and evaluated their immunogenicity and protective efficacy as mucosal booster vaccines for BCG given subcutaneously in early life. Intranasal delivery of MVA-AE to young adult mice induced CD4 and CD8 T cell responses to both Ag85A and ESAT-6 in lung mucosae.

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Aim: Cutaneous abscesses are one of the most common acute general surgery presentations. This study aimed to understand the current practice in the management of cutaneous abscesses in the United Kingdom (UK), once the decision has been made that acute surgical incision and drainage (I&D) is required.

Method: General surgeons from across the UK were surveyed on their opinions on the optimum management of cutaneous abscesses.

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Rationale: Pneumocystis pneumonia is a major cause of morbidity and mortality in HIV-infected subjects, cancer patients undergoing chemotherapy and solid organ transplant recipients. No vaccine is currently available. By chemical labeling coupled with proteomic approach, we have identified a putative surface protein (SPD1, Broad Institute gene accession number PNEG_01848) derived from single suspended P.

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Article Synopsis
  • Tuberculosis poses a significant health risk globally, especially for neonates and young infants who are more vulnerable to infection compared to adults.
  • The BCG vaccine, which is currently available, offers limited protection and is not safe for immunocompromised individuals, highlighting the need for a new vaccine that can be administered early in life and enhance future immunizations.
  • Research using gene-based vaccines expressing Ag85B from Mycobacterium tuberculosis shows potential for improving immune responses in neonates, with promising results from an initial DNA vaccine followed by an adenovirus booster, leading to better protection against tuberculosis challenges.
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Pneumocystis pneumonia is a major cause of morbidity and mortality in immunocompromised patients, particularly those infected with HIV. In this study, we evaluated the potential of oral immunization with live Pneumocystis to elicit protection against respiratory infection with Pneumocystis murina. C57BL/6 mice vaccinated with live P.

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Flagellin has been tested as a protein-based vaccine adjuvant, with the majority of studies focused on antibody responses. Here, we evaluated the adjuvant activity of flagellin for both cellular and humoral immune responses in BALB/c mice in the setting of gene-based immunization, and have made several novel observations. DNA vaccines and adenovirus (Ad) vectors were engineered to encode mycobacterial protein Ag85B, with or without flagellin of Salmonella typhimurium (FliC).

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There is an urgent need for effective prophylactic measures against Mycobacterium tuberculosis (Mtb) infection, particularly given the highly variable efficacy of Bacille Calmette-Guerin (BCG), the only licensed vaccine against tuberculosis (TB). Most studies indicate that cell-mediated immune responses involving both CD4+ and CD8+ T cells are necessary for effective immunity against Mtb. Genetic vaccination induces humoral and cellular immune responses, including CD4+ and CD8+ T-cell responses, against a variety of bacterial, viral, parasitic and tumor antigens, and this strategy may therefore hold promise for the development of more effective TB vaccines.

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Background: An important portion of asthmatics do not respond to current therapies. Thus, the need for new therapeutic drugs is urgent. We have demonstrated a critical role for PARP in experimental asthma.

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Four individuals die from active TB disease each minute, while at least 2 billion are latently infected and at risk for disease reactivation. BCG, the only licensed TB vaccine, is effective in preventing childhood forms of TB; however its poor efficacy in adults, emerging drug-resistant TB strains and tedious chemotherapy regimes, warrant the development of novel prophylactic measures. Designing safe and effective vaccines against TB will require novel approaches on several levels, including the administration of rationally selected mycobacterial antigens in efficient delivery vehicles via optimal immunization routes.

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Article Synopsis
  • Impairment of CD4+ T cells affects how well vaccines work, creating complications for immune responses.
  • CD40 ligand (CD40L) is crucial for immune responses and could help improve vaccine effectiveness in individuals with CD4+ T cell deficiency.
  • Experiments showed that co-immunizing mice with CD40L and a specific antigen significantly boosted T cell responses, suggesting CD40L may serve as a valuable adjuvant for vaccination strategies targeting those with weakened immune systems.
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Generation and isolation of recombinant herpesviruses by traditional homologous recombination methods can be a tedious, time-consuming process. Therefore, a novel stoplight recombination selection method was developed that facilitated rapid identification and purification of recombinant viruses expressing fusions of immunological epitopes with EGFP. This "traffic-light" approach provided a visual indication of the presence and purity of recombinant HSV-1 isolates by producing three identifying signals: (1) red fluorescence indicates non-recombinant viruses that should be avoided; (2) yellow fluorescence indicates cells co-infected with non-recombinant and recombinant viruses that are chosen with caution; (3) green fluorescence indicates pure recombinant isolates and to proceed with preparation of viral stocks.

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Background: Alcoholics are at heightened risk for developing active tuberculosis. This study evaluates chronic alcohol consumption in a murine model of vaccination with Mycobacterium bovis Bacille Calmette-Guèrin (BCG) and subsequent pulmonary infection with virulent Mycobacterium tuberculosis.

Methods: BALB/c mice were administered the Lieber-DeCarli liquid ethanol diet or pair-fed the liquid control diet for 3 weeks either before or after subcutaneous vaccination with M.

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We have examined the potential of a novel cytokine, interleukin-27 (IL-27), for gene therapy of prostate cancer. IL-27 is the most recently characterized member of the family of heterodimeric IL-12-related cytokines and has shown promise in halting tumor growth and mediating tumor regression in several cancer models. In the present study, we examined the efficacy of a new mode of gene delivery to prostate tumors: low-frequency ultrasound irradiation or "sonoporation.

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In this study we have firstly compared a range of recombinant DNA poxvirus prime-boost immunisation strategies and shown that combined intramuscular (i.m.) 2× DNA-HIV/intranasal (i.

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Significant safety issues have emerged concerning the general use of DRYVAX vaccine. Vaccination with replication-defective recombinant adenovirus (rAd) vaccines may offer a safer and effective alternative to live vaccinia virus (VV) vaccination. Six individual poxvirus glycoproteins: A33R, A34R, A36R, B5R, A27L or L1R that are normally expressed on the surface of infectious vaccinia virus were encoded in rAd vaccines and tested in mice in this study.

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Objective: Interleukin (IL)-17, which now defines the Th(17) immune response, is a critical cytokine expressed and required for stress granulopoiesis during microbial invasion. Dendritic cells (DC) can instigate this response by inducing IL-17 expression in CD4(+) T cells. Besides IL-17, microbial invasion also stimulates production of the DC growth factor granulocyte-macrophage colony-stimulating factor (GM-CSF).

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The type I IFNs exert a range of activities that include antiviral, antiproliferative, and immunomodulatory effects. To study this further, we have constructed recombinant vaccinia viruses expressing HIV or hemagglutinin (HA) Ags along with murine type I IFNs, IFN-alpha(4) (HA-VV-IFN-alpha(4)), IFN-beta (HA-VV-IFN-beta), or IFN-epsilon (HIV-VV-IFN-epsilon), a recently discovered member of this family. Our aims were to characterize IFN-epsilon functionality as a type I IFN and also to study the biological properties of these factors toward the development of safer and more effective vector-based vaccines.

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We have tested the efficacy of recombinant fowl pox (rFPV) and recombinant vaccinia virus (rVV) encoding antigens of AE clade HIV-1 in a prime-boost strategy, using both systemic and mucosal delivery routes. Of the various vaccine routes tested, intranasal/intramuscular (i.n.

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Depletion or dysfunction of CD4+ T lymphocytes profoundly perturbs host defenses and impairs immunogenicity of vaccines. Here, we show that plasmid DNA vaccination with a cassette encoding antigen (OVA) and a second cassette encoding full-length CD40 ligand (CD40L), a molecule expressed on activated CD4+ T lymphocytes and critical for T cell helper function, can elicit significant titers of antigen-specific immunoglobulins in serum and Tc1 CD8+ T cell responses in CD4-deficient mice. To investigate whether this approach leads to CD4+ T cell-independent vaccine protection against a prototypic AIDS-defining infection, Pneumocystis (PC) pneumonia, we used serum from mice vaccinated with PC-pulsed, CD40L-modified DCs to immunoprecipitate PC antigens.

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Interleukin-23 (IL-23) is a heterodimeric cytokine that shares IL-12 p40 but contains a unique p19 subunit similar to IL-12 p35. Previous studies indicate a greater importance for intact IL-12/23 p40 expression than IL-12 p35 for immunity against Mycobacterium tuberculosis, suggesting a role for IL-23 in host defense. The effects of IL-23 on the outcome of pulmonary infection with M.

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