42 research outputs found
T helper cell subsets specific for pseudomonas aeruginosa in healthy individuals and patients with cystic fibrosis
Background: We set out to determine the magnitude of antigen-specific memory T helper cell responses to Pseudomonas aeruginosa in healthy humans and patients with cystic fibrosis.
Methods: Peripheral blood human memory CD4+ T cells were co-cultured with dendritic cells that had been infected with different strains of Pseudomonas aeruginosa. The T helper response was determined by measuring proliferation, immunoassay of cytokine output, and immunostaining of intracellular cytokines.
Results: Healthy individuals and patients with cystic fibrosis had robust antigen-specific memory CD4+ T cell responses to Pseudomonas aeruginosa that not only contained a Th1 and Th17 component but also Th22 cells. In contrast to previous descriptions of human Th22 cells, these Pseudomonal-specific Th22 cells lacked the skin homing markers CCR4 or CCR10, although were CCR6+. Healthy individuals and patients with cystic fibrosis had similar levels of Th22 cells, but the patient group had significantly fewer Th17 cells in peripheral blood.
Conclusions: Th22 cells specific to Pseudomonas aeruginosa are induced in both healthy individuals and patients with cystic fibrosis. Along with Th17 cells, they may play an important role in the pulmonary response to this microbe in patients with cystic fibrosis and other conditions
Perception, Action and the Social Dynamics of the Variable Self
PostprintPeer reviewe
Development of a Standardized Screening Rule for Tuberculosis in People Living with HIV in Resource-Constrained Settings: Individual Participant Data Meta-analysis of Observational Studies
Haileyesus Getahun and colleagues report the development of a simple, standardized tuberculosis (TB) screening rule for resource-constrained settings, to identify people living with HIV who need further investigation for TB disease
The Dichotomous Pattern of IL-12R and IL-23R Expression Elucidates the Role of IL-12 and IL-23 in Inflammation
IL-12 and IL-23 cytokines respectively drive Th1 and Th17 type responses. Yet, little is known regarding the biology of these receptors. As the IL-12 and IL-23 receptors share a common subunit, it has been assumed that these receptors are co-expressed. Surprisingly, we find that the expression of each of these receptors is restricted to specific cell types, in both mouse and human. Indeed, although IL-12RΞ²2 is expressed by NK cells and a subset of Ξ³Ξ΄ T cells, the expression of IL-23R is restricted to specific T cell subsets, a small number of B cells and innate lymphoid cells. By exploiting an IL-12- and IL-23-dependent mouse model of innate inflammation, we demonstrate an intricate interplay between IL-12RΞ²2 NK cells and IL-23R innate lymphoid cells with respectively dominant roles in the regulation of systemic versus local inflammatory responses. Together, these findings support an unforeseen lineage-specific dichotomy in the in vivo role of both the IL-12 and IL-23 pathways in pathological inflammatory states, which may allow more accurate dissection of the roles of these receptors in chronic inflammatory diseases in humans
Cost effectiveness of cryptococcal antigen screening as a strategy to prevent HIV-associated cryptococcal meningitis in South Africa.
OBJECTIVES: Cryptococcal meningitis (CM)-related mortality may be prevented by screening patients for sub-clinical cryptococcal antigenaemia (CRAG) at antiretroviral-therapy (ART) initiation and pre-emptively treating those testing positive. Prior to programmatic implementation in South Africa we performed a cost-effectiveness analysis of alternative preventive strategies for CM. DESIGN: Cost-effectiveness analysis. METHODS: Using South African data we modelled the cost-effectiveness of four strategies for patients with CD4 cell-counts <100 cells/Β΅l starting ART 1) no screening or prophylaxis (standard of care), 2) universal primary fluconazole prophylaxis, 3) CRAG screening with fluconazole treatment if antigen-positive, 4) CRAG screening with lumbar puncture if antigen-positive and either amphotericin-B for those with CNS disease or fluconazole for those without. Analysis was limited to the first year of ART. RESULTS: The least costly strategy was CRAG screening followed by high-dose fluconazole treatment of all CRAG-positive individuals. This strategy dominated the standard of care at CRAG prevalence β₯0.6%. Although CRAG screening followed by lumbar puncture in all antigen-positive individuals was the most effective strategy clinically, the incremental benefit of LPs and amphotericin therapy for those with CNS disease was small and additional costs were large (US51 per person year; incremental cost effectiveness ratio(ICER) US20,495). CONCLUSIONS: CRAG screening would be a cost-effective strategy to prevent CM-related mortality among patients initiating ART in South Africa. These findings provide further justification for programmatic implementation of CRAG screening
Tuberculosis in the United Kingdom and Republic of Ireland
Aims: To describe the clinical features, diagnosis, and management of children with tuberculosis in the United Kingdom and Republic of Ireland.
Methods: Cases of culture-confirmed and clinically diagnosed tuberculosis were reported to the British Paediatric Surveillance Unit from December 2003 to January 2005.
Results: In total, 385 eligible cases were reported. Pulmonary disease was present in 154 (40%) children. Just over half (197, 51%) of children presented clinically and most of the remainder (166, 43%) at contact tracing. A probable source case was identified for 73/197 (36%) of the children presenting clinically. The majority (253, 66%) of children had a microbiological and/or histological investigation, and culture results were available for 240 (62%) children, of whom 102 (26%) were culture-positive. Drug resistance was reported in 15 (0.4%) cases. Forty-four percent (128/292) of non-white children did not receive the recommended quadruple drug therapy. Seven children died. Only 57% (217) of children were managed by a paediatric subspecialist in respiratory or infectious diseases or a general paediatrician with a special interest in one of these areas. Fewer than five cases were reported from 119/143 (83%) respondents and 72 of 96 (75%) centres.
Conclusions: Many paediatricians and centres see few children with tuberculosis. This may affect adherence to national guidelines. Managed clinical networks for children with tuberculosis may improve management and should be the standard of care