RESUMO
RATIONALE: Current immunodiagnostic tests for tuberculosis (TB), including the tuberculin skin test and IFN-γ release assay (IGRA), have significant limitations, which include their inability to distinguish between latent TB infection (LTBI) and active TB, a distinction critical for clinical management. OBJECTIVES: To identify mycobacteria-specific cytokine biomarkers that characterize TB infection, determine their diagnostic performance characteristics, and establish whether these biomarkers can distinguish between LTBI and active TB. METHODS: A total of 149 children investigated for TB infection were recruited; all participants underwent a tuberculin skin test and QuantiFERON-TB Gold assay. In parallel, whole-blood assays using early secretory antigenic target-6, culture filtrate protein-10, and PPD as stimulatory antigens were undertaken, and cytokine responses were determined by xMAP multiplex assays. MEASUREMENTS AND MAIN RESULTS: IFN-γ, interferon-inducible protein-10 (IP-10), tumor necrosis factor (TNF)-α, IL-1ra, IL-2, IL-13, and MIP-1ß (macrophage inflammatory protein-1ß) responses were significantly higher in LTBI and active TB cases than in TB-uninfected individuals, irrespective of the stimulant. Receiver operating characteristic analyses showed that IP-10, TNF-α, and IL-2 responses achieved high sensitivity and specificity for the distinction between TB-uninfected and TB-infected individuals. TNF-α, IL-1ra, and IL-10 responses had the greatest ability to distinguish between LTBI and active TB cases; the combinations of TNF-α/IL-1ra and TNF-α/IL-10 achieved correct classification of 95.5% and 100% of cases, respectively. CONCLUSIONS: We identified several mycobacteria-specific cytokine biomarkers with the potential to be exploited for immunodiagnosis. Incorporation of these biomarkers into future immunodiagnostic assays for TB could result in substantial gains in sensitivity and allow the distinction between LTBI and active TB based on a blood test alone.
Assuntos
Quimiocina CCL4/sangue , Quimiocina CXCL10/sangue , Interferon gama/sangue , Interleucinas/sangue , Tuberculose Latente/diagnóstico , Fator de Necrose Tumoral alfa/sangue , Adolescente , Biomarcadores/sangue , Criança , Pré-Escolar , Estudos de Coortes , Diagnóstico Diferencial , Feminino , Humanos , Tuberculose Latente/sangue , Masculino , Valor Preditivo dos Testes , Curva ROCRESUMO
BACKGROUND: Culture-independent analysis of the respiratory secretions of people with cystic fibrosis (CF) has identified many bacterial species not previously detected using culture in this context. However, little is known about their clinical significance or persistence in CF airways. METHODS: The authors characterised the viable bacterial communities in the sputum collected from 14 patients at monthly intervals over 1 year using a molecular community profiling technique-terminal restriction fragment length polymorphism. Clinical characteristics were also collected, including lung function and medications. Ecological community measures were determined for each sample. Microbial community change over time within subjects was defined using ecological analytical tools, and these measures were compared between subjects and to clinical features. RESULTS: Bacterial communities were stable within subjects over time but varied between subjects, despite similarities in clinical course. Antibiotic therapy temporarily perturbed these communities which generally returned to pretreatment configurations within 1 month. Species usually considered CF pathogens and those not previously regarded as such exhibited similar patterns of persistence. Less diverse sputum bacterial communities were correlated to lung disease severity and relative abundance of Pseudomonas aeruginosa. CONCLUSION: Whilst not true in all cases, the microbial communities that chronically infect the airways of patients with CF can vary little over a year despite antibiotic perturbation. The species present tended to vary more between than within subjects, suggesting that each CF airway infection is unique, with relatively stable and resilient bacterial communities. The inverse relationship between community richness and disease severity is similar to findings reported in other mucosal infections.
Assuntos
Fibrose Cística/microbiologia , Sistema Respiratório/microbiologia , Escarro/microbiologia , Adulto , Antibacterianos/farmacologia , Carga Bacteriana/efeitos dos fármacos , Biodiversidade , Fibrose Cística/tratamento farmacológico , Fibrose Cística/fisiopatologia , Progressão da Doença , Feminino , Humanos , Masculino , Metagenoma , Polimorfismo de Fragmento de Restrição , Análise de Componente PrincipalRESUMO
The chemokine CXCL12 and its receptor CXCR4 are expressed widely in human cancers, including ovarian cancer, in which they are associated with disease progression at the levels of tumor cell proliferation, invasion, and angiogenesis. Here, we used an immunocompetent mouse model of intraperitoneal papillary epithelial ovarian cancer to show that modulation of the CXCL12/CXCR4 axis in ovarian cancer has multimodal effects on tumor pathogenesis associated with induction of antitumor immunity. siRNA-mediated knockdown of CXCL12 in BR5-1 cells that constitutively express CXCL12 and CXCR4 reduced cell proliferation in vitro, and tumor growth in vivo. Similarly, treatment of BR5-1-derived tumors with AMD3100, a selective CXCR4 antagonist, resulted in increased tumor apoptosis and necrosis, reduction in intraperitoneal dissemination, and selective reduction of intratumoral FoxP3(+) regulatory T cells (Treg). Compared with controls, CXCR4 blockade greatly increased T-cell-mediated antitumor immune responses, conferring a significant survival advantage to AMD3100-treated mice. In addition, the selective effect of CXCR4 antagonism on intratumoral Tregs was associated with both higher CXCR4 expression and increased chemotactic responses to CXCL12, a finding that was also confirmed in a melanoma model. Together, our findings reinforce the concept of a critical role for the CXCL12/CXCR4 axis in ovarian cancer pathogenesis, and they offer a definitive preclinical validation of CXCR4 as a therapeutic target in this disease.
Assuntos
Quimiocina CXCL12/genética , Modelos Animais de Doenças , Imunocompetência , Neoplasias Ovarianas/metabolismo , Receptores CXCR4/genética , Animais , Apoptose , Proliferação de Células , Ensaio de Imunoadsorção Enzimática , Feminino , Técnicas de Silenciamento de Genes , Camundongos , Neoplasias Ovarianas/imunologia , Neoplasias Ovarianas/patologia , Interferência de RNA , Taxa de SobrevidaRESUMO
BACKGROUND: Cystic Fibrosis (CF) lung disease is characterised by an inexorable decline in lung function, punctuated by periods of symptomatic worsening known as pulmonary exacerbations (referred to here as CFPE). Despite their clinical significance, the cause of CFPE remains undetermined. It has been suggested that an increase in bacterial density may be a trigger, although this has not been shown empirically. METHODS: Here, a previously validated quantitative PCR-based approach was used to assess numbers of Pseudomonas aeruginosa and of total bacteria in respiratory secretions from patients during the period leading up to CFPE. Sputum samples collected from 12 adult CF patients were selected retrospectively to fall approximately 21, 14, 7 and 0 days prior to CFPE diagnosis. In addition, the relationships between clinical parameters (FEV(1), temperature and patient reported outcome measures) and microbiological data were investigated. RESULTS: No significant changes either in total bacterial or P. aeruginosa numbers were identified prior to CFPE. Of all the correlations tested, only temperature showed a significant correlation with total bacterial numbers in the period leading to CFPE. CONCLUSIONS: These findings strongly suggest that CFPE do not generally result from increased bacterial density within the airways. Instead, data presented here are consistent with alternative models of pulmonary exacerbation.
Assuntos
Carga Bacteriana , Fibrose Cística/microbiologia , Pneumonia Bacteriana/microbiologia , Infecções por Pseudomonas/microbiologia , Pseudomonas aeruginosa/crescimento & desenvolvimento , Escarro/microbiologia , Adolescente , Adulto , Antibacterianos/uso terapêutico , Fibrose Cística/fisiopatologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Pneumonia Bacteriana/diagnóstico , Pneumonia Bacteriana/tratamento farmacológico , Pneumonia Bacteriana/fisiopatologia , Infecções por Pseudomonas/diagnóstico , Infecções por Pseudomonas/tratamento farmacológico , Infecções por Pseudomonas/fisiopatologia , Pseudomonas aeruginosa/genética , Pseudomonas aeruginosa/isolamento & purificação , Reação em Cadeia da Polimerase em Tempo Real , Testes de Função Respiratória , Índice de Gravidade de Doença , Adulto JovemRESUMO
The aim of this study was to determine whether geographical differences impact the composition of bacterial communities present in the airways of cystic fibrosis (CF) patients attending CF centers in the United States or United Kingdom. Thirty-eight patients were matched on the basis of clinical parameters into 19 pairs comprised of one U.S. and one United Kingdom patient. Analysis was performed to determine what, if any, bacterial correlates could be identified. Two culture-independent strategies were used: terminal restriction fragment length polymorphism (T-RFLP) profiling and 16S rRNA clone sequencing. Overall, 73 different terminal restriction fragment lengths were detected, ranging from 2 to 10 for U.S. and 2 to 15 for United Kingdom patients. The statistical analysis of T-RFLP data indicated that patient pairing was successful and revealed substantial transatlantic similarities in the bacterial communities. A small number of bands was present in the vast majority of patients in both locations, indicating that these are species common to the CF lung. Clone sequence analysis also revealed that a number of species not traditionally associated with the CF lung were present in both sample groups. The species number per sample was similar, but differences in species presence were observed between sample groups. Cluster analysis revealed geographical differences in bacterial presence and relative species abundance. Overall, the U.S. samples showed tighter clustering with each other compared to that of United Kingdom samples, which may reflect the lower diversity detected in the U.S. sample group. The impact of cross-infection and biogeography is considered, and the implications for treating CF lung infections also are discussed.
Assuntos
Bactérias/classificação , Bactérias/isolamento & purificação , Biodiversidade , Fibrose Cística/microbiologia , Pulmão/microbiologia , Adolescente , Adulto , Bactérias/genética , Análise por Conglomerados , DNA Bacteriano/química , DNA Bacteriano/genética , DNA Ribossômico/química , DNA Ribossômico/genética , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Dados de Sequência Molecular , Filogenia , Polimorfismo de Fragmento de Restrição , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Reino Unido , Estados Unidos , Adulto JovemRESUMO
A 55-year-old woman with primary Immunoglobulin light chain (AL) systemic amyloidosis died due to spontaneous rupture of her liver following treatment with high-dose melphalan and autologous stem cell transplant (HDM/SCT). She was first diagnosed after developing nephrotic-range proteinuria. Spontaneous rupture of her liver occurred 10 days after treatment with HDM/SCT and was complicated by septic shock. She was not eligible for surgical intervention and died shortly after. Amyloid fibrils were extracted from the autopsied liver sample (05-135L) and the biochemical nature of the fibrils was analyzed using electrophoretic and immunohistochemical techniques. Our testing showed that the fibrils were composed of immunoglobulin lambda light chains that were not glycosylated. While the liver is often involved in AL amyloidosis, this is the first documented case of a spontaneous hepatic rupture in a patient during treatment with HDM/SCT. A literature review of spontaneous liver rupture in patients with amyloidosis is presented.