Publications by authors named "Kelleher P"

Bacteria possess (bacterio)phage defence systems to ensure their survival. The thermophilic lactic acid bacterium, Streptococcus thermophilus, which is used in dairy fermentations, harbours multiple CRISPR-Cas and restriction and modification (R/M) systems to protect itself against phage attack, with limited reports on other types of phage-resistance. Here, we describe the systematic identification and functional analysis of the phage resistome of S.

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Until the late 2000s, lactococci substantially contributed to the discovery of various plasmid-borne phage defence systems, rendering these bacteria an excellent antiphage discovery resource. Recently, there has been a resurgence of interest in identifying novel antiphage systems in lactic acid bacteria owing to recent reports of so-called 'defence islands' in diverse bacterial genera. Here, 321 plasmid sequences from 53 lactococcal strains were scrutinized for the presence of antiphage systems.

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Over the last 15 years activity of diagnostic flow cytometry services have evolved from monitoring of CD4 T cell subsets in HIV-1 infection to screening for primary and secondary immune deficiencies syndromes and assessment of immune constitution following B cell depleting therapy and transplantation. Changes in laboratory activity in high income countries have been driven by initiation of anti-retroviral therapy (ART) in HIV-1 regardless of CD4 T cell counts, increasing recognition of primary immune deficiency syndromes and the wider application of B cell depleting therapy and transplantation in clinical practice. Laboratories should use their experience in standardization and quality assurance of CD4 T cell counting in HIV-1 infection to provide immune monitoring services to patients with primary and secondary immune deficiencies.

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Article Synopsis
  • - Black women, particularly those in the carceral system, face severe health challenges, including heightened risks for HIV/STIs and chronic diseases, highlighting a need for improved healthcare access and experiences.
  • - A study with 43 Black women in New York City revealed key barriers to healthcare, including provider mistrust, perceived disrespect, lack of effective health communication, and low health literacy.
  • - To foster better healthcare relationships, the study emphasizes the need for accountability in healthcare providers, improved diversity training, responsiveness to patient feedback, and an increase in Black medical professionals.
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The distinct conjugation machineries encoded by plasmids pNP40 and pUC11B represent the most prevalent plasmid transfer systems among lactococcal strains. In the current study, we identified genetic determinants that underpin pNP40- and pUC11B-mediated, high-frequency mobilisation of other, non-conjugative plasmids. The mobilisation frequencies of the smaller, non-conjugative plasmids and the minimal sequences required for their mobilisation were determined, owing to the determination of the oriT sequences of both pNP40 and pUC11B, which allowed the identification of similar sequences in some of the non-conjugative plasmids that were shown to promote their mobilisation.

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Plasmids pNP40 and pUC11B encode two prevalent yet divergent conjugation systems, which have been characterized in detail recently. Here, we report the elucidation of the putative adhesins of the pNP40 and pUC11B conjugation systems, encoded by and , respectively. Despite their significant sequence divergence, TraAd and TrsAd represent the most conserved component between the pNP40- and the pUC11B-encoded conjugation systems and share similar peptidoglycan-hydrolase domains.

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Lactococcal conjugative plasmids are poorly characterized compared to those harbored by numerous other Gram-positive bacteria, despite their significance in dairy fermentations and starter culture development. Furthermore, the transcriptional landscape of these lactococcal conjugation systems and their regulation have not been studied in any detail. Lactococcal plasmids pNP40 and pUC11B possess two genetically distinct and prevalent conjugation systems.

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Background: Herpes simplex virus (HSV) is a common infection, affecting the majority of the population by age of 50. Recurrent symptomatic outbreaks, experienced by a minority, have significant psychological and psychosexual effects. The varicella zoster virus (VZV), resembling HSV, shows potential for a functional cure via vaccination.

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Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) immune responses and infection outcomes were evaluated in 2,686 patients with varying immune-suppressive disease states after administration of two Coronavirus Disease 2019 (COVID-19) vaccines. Overall, 255 of 2,204 (12%) patients failed to develop anti-spike antibodies, with an additional 600 of 2,204 (27%) patients generating low levels (<380 AU ml). Vaccine failure rates were highest in ANCA-associated vasculitis on rituximab (21/29, 72%), hemodialysis on immunosuppressive therapy (6/30, 20%) and solid organ transplant recipients (20/81, 25% and 141/458, 31%).

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Plasmid pUC11B is a 49.3-kb plasmid harboured by the fermented meat isolate Lactococcus lactis subsp. lactis UC11.

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SARS-CoV-2 vaccines are recommended pre-transplantation, however, waning immunity and evolving variants mandate booster doses. Currently there no data to inform the optimal timing of booster doses post-transplant, in patients primed pre-transplant. We investigated serial serological samples in 204 transplant recipients who received 2 or 3 SARS-CoV-2 vaccines pre-transplant.

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Background: Granulomatous and lymphocytic interstitial lung disease (gl-ILD) is a major cause of morbidity and mortality among patients with common variable immunodeficiency. Corticosteroids are recommended as first-line treatment for gl-ILD, but evidence for their efficacy is lacking.

Objectives: This study analyzed the effect of high-dose corticosteroids (≥0.

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Interstitial lung disease and associated fibrosis occur in a proportion of individuals who have recovered from severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection through unknown mechanisms. We studied individuals with severe coronavirus disease 2019 (COVID-19) after recovery from acute illness. Individuals with evidence of interstitial lung changes at 3 to 6 months after recovery had an up-regulated neutrophil-associated immune signature including increased chemokines, proteases, and markers of neutrophil extracellular traps that were detectable in the blood.

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Article Synopsis
  • The rhamnose-glucose polysaccharide (Rgp) from Streptococcus thermophilus is crucial for its cell wall and has been linked to genetic diversity across different strains, with two new genotypes identified in this study.
  • Researchers analyzed 78 S. thermophilus genomes, revealing that the genetic makeup influences the structure of Rgp, which plays a key role in the bacteria's interactions with bacteriophages.
  • A multiplex PCR system was developed to classify these strains based on their unique genetic content related to Rgp biosynthesis, which is significant for dairy fermentations where S. thermophilus is commonly used and is susceptible to phage attacks.
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The first step in phage infection is the recognition of, and adsorption to, a receptor located on the host cell surface. This reversible host adsorption step is commonly followed by an irreversible event, which involves phage DNA delivery or release into the bacterial cytoplasm. The molecular components that trigger this latter event are unknown for most phages of Gram-positive bacteria.

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Article Synopsis
  • This study evaluates the immunogenicity and effectiveness of two COVID-19 vaccines (BNT162B2 and ChAdOx1) in patients undergoing haemodialysis, who are at higher risk for severe illness from COVID-19.
  • The research involved 1021 haemodialysis patients, tracking their antibody responses and overall health post-vaccination, finding that BNT162B2 produced significantly higher antibody levels than ChAdOx1.
  • The findings indicate that while both vaccines offered substantial protection against severe outcomes, antibody levels could predict the risk of breakthrough infections, suggesting that continuous monitoring of antibody responses could be beneficial in this vulnerable population.
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Background: Solid organ transplant recipients have attenuated immune responses to SARS-CoV-2 vaccines. In this study, we report on immune responses to 3rd- (V3) and 4th- (V4) doses of heterologous and homologous vaccines in a kidney transplant population.

Methods: We undertook a single centre cohort study of 724 kidney transplant recipients prospectively screened for serological responses following 3 primary doses of a SARS-CoV2 vaccine.

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Up to 3.8% of human T-lymphotropic virus type-1 (HTLV-1)-infected asymptomatic carriers (AC) eventually develop HTLV-1-associated myelopathy (HAM). HAM occurs in patients with high (> 1%) HTLV proviral load (PVL).

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Lateral flow immunoassays (LFIAs) are able to achieve affordable, large scale antibody testing and provide rapid results without the support of central laboratories. As part of the development of the REACT programme extensive evaluation of LFIA performance was undertaken with individuals following natural infection. Here we assess the performance of the selected LFIA to detect antibody responses in individuals who have received at least one dose of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) vaccine.

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Background: Respiratory tract infection (RTI) is a leading cause of training and in-competition time-loss in athlete health. The immune factors associated with RTI susceptibility remain unclear. In this study, we prospectively characterise host immune factors in elite athletes exhibiting RTI susceptibility.

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We report the structural evolutions of water networks and solvatochromic response of the CHNO radical anion in the OH and CH stretching regions by analysis of the vibrational spectra displayed by cryogenically cooled CHNO·(HO) clusters. The OH stretching bands evolve with a surprisingly large discontinuity at = 6, which features the emergence of an intense, strongly red-shifted band along with a weaker feature that appears in the region assigned to a free OH fundamental. Very similar behavior is displayed by the perdeuterated carboxylate clusters, RCO·(HO) (R = CDCD), indicating that this behavior is a general feature in the microhydration of the triatomic anionic domain and not associated with CH oscillators.

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Competence refers to the specialized physiological state in which bacteria undergo transformation through the internalization of exogenous DNA in a controlled and genetically encoded process that leads to genotypic and, in many cases, phenotypic changes. Natural transformation was first described in and has since been demonstrated in numerous species, including and . Homologs of the genes encoding the DNA uptake machinery for natural transformation have been reported to be present in several lactic acid bacteria, including spp.

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On October 29, 2021, the Pfizer-BioNTech pediatric COVID-19 vaccine received Emergency Use Authorization for children aged 5-11 years in the United States. For a successful immunization program, both access to and uptake of the vaccine are needed. Fifteen million doses were initially made available to pediatric providers to ensure the broadest possible access for the estimated 28 million eligible children aged 5-11 years, especially those in high social vulnerability index (SVI) communities.

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