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1.
Eur J Clin Microbiol Infect Dis ; 36(10): 1933-1938, 2017 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-28589425

RESUMEN

The use of urinary antigen tests (UATs) may provide early etiology in pneumonia, and facilitates rapid and directed antibiotic treatment. In this study, we evaluated the novel lateral flow ImmuView Streptococcus pneumoniae and Legionella pneumophila UAT, which detects pneumococcal and L. pneumophila serogroup 1 antigens in a combined test. We compared the ImmuView UAT with the BinaxNOW S. pneumoniae UAT and the BinaxNOW L. pneumophila UAT in 147 patients with pneumococcal bacteremia (n = 48), non-pneumococcal non-Legionella bacteremia (n = 93) and Legionella infections in the lower airways (L. pneumophila, n = 5; L. bozemanii, n = 1). In three cases, the ImmuView test was invalid before and after boiling while the BinaxNOW tests were valid in all cases. In 144 cases, the three UATs demonstrated a very good inter-assay agreement for detection of pneumococcal antigen (κ = 0.86) and L. pneumophila antigen (κ = 1.00). The ImmuView and BinaxNOW S. pneumoniae tests had similar sensitivities (62% vs 60%; p = ns) in 48 cases with pneumococcal bacteremia and both tests had specificities of 97% in 96 cases with non-pneumococcal infections. Furthermore, the ImmuView and BinaxNOW L. pneumophila tests were positive for Legionella antigen in five patients with confirmed L. pneumophila serogroup 1 infections, and negative in all non-L. pneumophila cases. The ImmuView and BinaxNOW tests performed similarly when evaluated on urine samples from bacteremic and non-bacteremic patients with identified etiology.


Asunto(s)
Antígenos Bacterianos/análisis , Pruebas Diagnósticas de Rutina/métodos , Inmunoensayo/métodos , Legionella pneumophila/química , Neumonía Bacteriana/diagnóstico , Streptococcus pneumoniae/química , Orina/química , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Femenino , Humanos , Masculino , Persona de Mediana Edad , Polisacáridos Bacterianos/análisis , Sensibilidad y Especificidad , Adulto Joven
2.
Eur J Clin Microbiol Infect Dis ; 36(4): 657-662, 2017 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-27909820

RESUMEN

Capnocytophga canimorsus and Capnocytophga cynodegmi can be transmitted from cats and dogs to humans, and can cause a wide range of infections including wound infections, sepsis, or endocarditis. We and others recently discovered two new Capnocytophaga species, C. canis and C. stomatis, mainly associated with wound infections. The first-line treatment of animal bite related infections is penicillin, and in case of allergy, doxycycline and trimethoprim/sulfamethoxazole. However, there is a lack of antibiotic susceptibility patterns for animal bite associated Capnocytophaga species. Thus, we set out to study the antibiotic profiles against animal bite associated Capnocytophaga species isolated from wound and blood cultures after cat and dog bites and coupled the findings to whole genome sequencing data. A total of 24 strains were included in the study. Phenotypic analysis of antibiotic resistance was performed with E-tests. The web-based tool 'Resfinder' was used to identify resistance genes in the whole genome dataset. Two strains of C. cynodegmi and two strains of the recently discovered C. stomatis were resistant to penicillin (MIC > 24 mg/L) and cephalosporins (MIC > 24 mg/L), and three out of these strains also exhibited resistance to imipenem (MIC = 32 mg/L). Genomic analysis revealed that these strains carried a class D beta-lactamase gene, which has not previously been found in Capnocytophaga spp. A class D beta lactamase with broad substrate specificity was found in animal bite associated Capnocytophaga species, which could have important implications when treating wound infections after cat and dog bites. It also suggests that pet animal bacteria can harbour resistance genes with relevance for human infections.


Asunto(s)
Mordeduras y Picaduras/complicaciones , Capnocytophaga/enzimología , Infecciones por Bacterias Gramnegativas/microbiología , beta-Lactamasas/genética , beta-Lactamasas/metabolismo , beta-Lactamas/metabolismo , Animales , Capnocytophaga/genética , Capnocytophaga/aislamiento & purificación , Gatos , Biología Computacional , Pruebas Antimicrobianas de Difusión por Disco , Perros , Genoma Bacteriano , Humanos , Especificidad por Sustrato , beta-Lactamasas/clasificación
3.
Eur J Clin Microbiol Infect Dis ; 35(4): 579-85, 2016 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-26796552

RESUMEN

Rapid identification of Streptococcus pneumoniae in blood culture (BC) bottles is important for early directed antimicrobial therapy in pneumococcal bacteraemia. We evaluated a new latex agglutination (LA) test on BC bottles, the ImmuLex™ S. pneumoniae Omni (Statens Serum Institut, Denmark), and compared the performance with the Slidex® pneumo-Kit (bioMérieux, France) and the Wellcogen™ S. pneumoniae (Remel, UK) LA tests, as well as the BinaxNOW® S. pneumoniae (Alere, USA) antigen test. The four tests were directly applied on 358 positive BC bottles with Gram-positive cocci in pairs or chains and on 15 negative bottles. Valid test results were recorded in all cases for ImmuLex and BinaxNOW and in 88.5 % (330/373) and 94.1 % (351/373) of cases for Slidex and Wellcogen, respectively. Based on bottles positive for S. pneumoniae by conventional methods, the sensitivity of ImmuLex was 99.6 %, similar to the other tests (range, 99.6-100 %). Based on bottles positive for non-pneumococcal pathogens, the specificity of ImmuLex was 82.6 %, in comparison to 97.6 % for Slidex (p < 0.01) and 85.4 % for Wellcogen (p = ns). The BinaxNOW test had a lower specificity (64.1 %) than any LA test (p < 0.01). On BC bottles positive for α-haemolytic streptococci, ImmuLex was positive in 12/67 (17.9 %) cases, Slidex in 2/59 (3.4 %) cases, Wellcogen in 11/64 (17.2 %) cases and BinaxNOW in 25/67 (37.3 %) cases. In conclusion, the ImmuLex test provides a valid and sensitive technique for the rapid detection of S. pneumoniae in BC bottles, similar to the other compared methods. However, the specificity was sub-optimal, since the test may cross-react with other Gram-positive bacteria.


Asunto(s)
Bacteriemia/diagnóstico , Pruebas Diagnósticas de Rutina/métodos , Inmunoensayo/métodos , Infecciones Neumocócicas/diagnóstico , Streptococcus pneumoniae/aislamiento & purificación , Humanos , Sensibilidad y Especificidad , Factores de Tiempo
4.
Int Endod J ; 49(4): 343-51, 2016 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-25950381

RESUMEN

AIM: To elucidate the origin of Enterococcus faecalis isolated from secondary root canal infections and the possibility for a foodborne transmission by comparing them to strains recovered from food, blood and stool regarding putative virulence factors and antibiotic susceptibility profiles, where strains from common origin were hypothesized to harbour similar characteristics. METHODOLOGY: A total of 108 E. faecalis strains recovered in the county of Stockholm, Sweden, were screened using PCR for putative virulence factors esp, cylA, gelE/gelatinase-negative phenotype (ef1841/fsrC), efaA, ace and asa1. The minimum inhibitory concentration (MIC) for ampicillin, piperacillin-tazobactam, imipenem, gentamicin, vancomycin, ciprofloxacin and linezolid was determined using the agar dilution method. RESULTS: Next to strains from blood, the food isolates presented the highest average number of virulence determinants and were frequently enriched with asa1 coding for aggregation substance. None of the endodontic strains carried cylA, and the gelatinase-negative phenotype caused by a deletion dominated the group. Altogether, the most prevalent genes were gelE, efaA and ace, and a combination of them was equally present in approximately 80% of the strains from food, stool and root canals in comparison with 43.3% of the blood isolates. High-level resistance to ciprofloxacin and gentamicin was observed in 30% of the blood isolates, whereas the isolates from other origins, with single exceptions, were susceptible to all tested antibiotics. CONCLUSIONS: Evidence for a foodborne transmission, explaining the high reported prevalence of E. faecalis in root filled teeth, could not be determined based on the similarities in virulence factor patterns and antibiotic susceptibility. The only linkage between isolates from food and root canals consisted of a shared common combination of the genes gelE, efaA and ace. The high occurrence of putative virulence traits in food isolates questions the safety of E. faecalis in food products.


Asunto(s)
Enterococcus faecalis/aislamiento & purificación , Heces/microbiología , Contaminación de Alimentos , Periodontitis Periapical/microbiología , Tratamiento del Conducto Radicular , Antibacterianos/farmacología , Cultivo de Sangre , Farmacorresistencia Microbiana , Humanos , Pruebas de Sensibilidad Microbiana , Fenotipo , Reacción en Cadena de la Polimerasa , Pulpitis/cirugía , Suecia , Factores de Virulencia
5.
Eur J Clin Microbiol Infect Dis ; 34(8): 1583-8, 2015 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-25926305

RESUMEN

The performance of the recently commercialized Uni-Gold™ Streptococcus pneumoniae test for the detection of pneumococcal antigen in urine was studied in a multicenter study. First, we studied the interassay agreement between Uni-Gold™ and the BinaxNOW® S. pneumoniae urinary antigen test on 337 consecutive urine samples sent to the laboratory for the detection of pneumococcal antigen. The two tests performed similarly (κ = 0.82): both tests positive in 27 cases, both tests negative in 299 cases, and with divergent test results in 11 cases. Secondly, the tests were run on urine samples from 203 patients with bacteremia, including 51 patients with pneumococcal bacteremia. The sensitivities and specificities were 67 and 86 % for Uni-Gold™, and 57 % and 94 % for BinaxNOW®, respectively. The false-positivity rate was significantly higher for Uni-Gold™ compared with BinaxNOW® in patients with Escherichia coli bacteremia (15 vs. 2.1 %, p = 0.04), and tended to be higher in patients with bacteremia with alpha-hemolytic streptococci (32 vs. 11 %, p = 0.13). When cases with E. coli and alpha-hemolytic streptococci were excluded from the analysis, the overall false-positivity rate was 9/85 (11 %) for Uni-Gold™ and 6/85 (7.1 %) for BinaxNOW®. In conclusion, the study showed that Uni-Gold™ was not inferior to BinaxNOW® for the detection of pneumococcal urinary antigen in patients with pneumococcal bacteremia. The specificity of Uni-Gold™ was suboptimal due to false-positive results in cases with E. coli and alpha-hemolytic streptococci bacteremia. However, in patient populations usually subjected to testing for pneumococcal urinary antigen, such as pneumonia and meningitis patients, bacteremia with these pathogens is uncommon. The diagnostic usefulness of the Uni-Gold™ test should be further evaluated.


Asunto(s)
Antígenos Bacterianos/análisis , Bacteriemia/diagnóstico , Técnicas Bacteriológicas/métodos , Pruebas Diagnósticas de Rutina/métodos , Infecciones Neumocócicas/diagnóstico , Orina/química , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Reacciones Falso Positivas , Femenino , Humanos , Masculino , Persona de Mediana Edad , Estudios Prospectivos , Sensibilidad y Especificidad , Adulto Joven
6.
Eur J Clin Microbiol Infect Dis ; 31(11): 2983-7, 2012 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-22669561

RESUMEN

The purpose of this investigation was to evaluate the performance of the Bactec 9240 and BacT/Alert 3D blood culture systems in the detection of Candida spp. and bacteria in simulated polymicrobial sepsis models. A total of 28 clinical isolates of Escherichia coli, Staphylococcus aureus, Candida albicans, and Candida glabrata were studied. Five polymicrobial models of C. albicans + S. aureus, C. albicans + E. coli, C. glabrata + S. aureus, C. glabrata + E. coli, and C. albicans + C. glabrata were prepared. Each combination was inoculated in five different blood culture vials. The two systems were compared for culture positivity and time to detection (TTD). Twenty-four mixed cultures with a yeast and a bacteria were tested. Bactec Mycosis vials could detect yeasts in all 24 cultures. The aerobic vials from both Bactec and BacT/Alert could detect both yeasts and bacteria in 22/24 (91.66 %) cultures. Bactec Plus Anaerobic/F and BacT/Alert FN vials could detect both microorganisms in 19/24 (79.16 %) and 4/24 (16.67 %) vials, respectively. Seven polymicrobial sepsis models with C. albicans + C. glabrata were also tested. Mycosis vials could detect both yeasts in 7/7 mixed cultures. The aerobic vials from Bactec and BacT/Alert could detect both yeasts in 3/7 and 2/7 mixed cultures, respectively. Bactec Plus Aerobic/F had a shorter TTD compared to BacT/Alert FA and Bactec Plus Anaerobic/F vials (p < 0.0001 and p < 0.01, respectively). The present study shows that the Bactec and BacT/Alert systems have different characteristics in the detection of yeasts and bacteria with polymicrobial sepsis.


Asunto(s)
Bacteriemia/diagnóstico , Sangre/microbiología , Candidemia/diagnóstico , Coinfección/diagnóstico , Técnicas Microbiológicas/métodos , Bacteriemia/microbiología , Candida/clasificación , Candida/aislamiento & purificación , Candidemia/microbiología , Coinfección/microbiología , Escherichia coli/clasificación , Escherichia coli/aislamiento & purificación , Humanos , Modelos Teóricos , Sensibilidad y Especificidad , Staphylococcus aureus/clasificación , Staphylococcus aureus/aislamiento & purificación , Factores de Tiempo
7.
Eur J Clin Microbiol Infect Dis ; 31(11): 3073-7, 2012 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-22706514

RESUMEN

The purpose of this investigation was to compare the performance of species-specific polymerase chain reaction (PCR), matrix-assisted laser desorption/ionisation time-of-flight mass spectrometry (MALDI-TOF MS) and phenotypic identification systems for the identification of Enterococcus species. A total of 132 clinical isolates were investigated by the following: (1) a multiplex real-time PCR assay targeting ddl Enterococcus faecium, ddl Enterococcus faecalis, vanC1 and vanC2/C3 genes, and a high-resolution melting (HRM) analysis of the groESL gene for the differentiation of Enterococcus casseliflavus and Enterococcus gallinarum; (2) Bruker MS; (3) VITEK MS; and (4) the VITEK 2 system. 16S rRNA gene sequencing was used as a reference method in the study. The 132 isolates were identified as 32 E. faecalis, 63 E. faecium, 16 E. casseliflavus and 21 E. gallinarum. The multiplex PCR, Bruker MS and VITEK MS were able to identify all the isolates correctly at the species level. The VITEK 2 system could identify 131/132 (99.2 %) and 121/132 (91.7 %) of the isolates at the genus and species levels, respectively. The HRM-groESL assay identified all (21/21) E. gallinarum isolates and 81.3 % (13/16) of the E. casseliflavus isolates. The PCR methods described in the present study are effective in identifying the enterococcal species. MALDI-TOF MS is a rapid, reliable and cost-effective identification technique for enterococci. The VITEK 2 system is less efficient at detecting non-faecalis and non-faecium Enterococcus species.


Asunto(s)
Técnicas de Tipificación Bacteriana/métodos , Técnicas Bacteriológicas/métodos , Enterococcus/clasificación , Enterococcus/aislamiento & purificación , Infecciones por Bacterias Grampositivas/diagnóstico , Reacción en Cadena de la Polimerasa/métodos , Espectrometría de Masa por Láser de Matriz Asistida de Ionización Desorción/métodos , Técnicas de Tipificación Bacteriana/economía , Técnicas Bacteriológicas/economía , Costos y Análisis de Costo , Enterococcus/química , Enterococcus/genética , Humanos , Reacción en Cadena de la Polimerasa/economía , Sensibilidad y Especificidad , Espectrometría de Masa por Láser de Matriz Asistida de Ionización Desorción/economía
8.
Eur J Clin Microbiol Infect Dis ; 31(10): 2631-7, 2012 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-22454088

RESUMEN

Capnocytophaga canimorsus and C. cynodegmi are gram negative bacteria that can be transmitted to humans from dogs or cats and cause serious infections. Routine bacteriological methods, including fermentation and phenotypic tests are insufficient to correctly identify C. canimorsus or C. cynodegmi. The aim of this study was to evaluate the performance of VITEK2 and MALDI-TOF in identification of these bacteria. Twenty two isolates that were identified as C. canimorsus / C. cynodegmi by 16S rRNA sequencing were included in the study and were further investigated with VITEK2 and MALDI-TOF. A Capnocytophaga species-specific PCR was used as the reference method. Out of 22 included isolates, the species-specific PCR identified six blood isolates as C. canimorsus and 14 wound isolates as C. cynodegmi. Two isolates could not be identified with the reference method. VITEK2 identified 10/20 isolates correctly to Capnocytophaga spp. MALDI-TOF analysis correctly identified 6/6 C. canimorsus and 13/14 C. cynodegmi isolates. The mean time to identification with VITEK2 was 6 hours whereas MALDI-TOF required approximately 10 minutes per sample. Here we show that MALDI-TOF rapidly identified C. canimorsus and C. cynodegmi and thus constitutes a valuable diagnostic tool in the clinical laboratory.


Asunto(s)
Patógenos Transmitidos por la Sangre/aislamiento & purificación , Sangre/microbiología , Capnocytophaga/aislamiento & purificación , Espectrometría de Masa por Láser de Matriz Asistida de Ionización Desorción/métodos , Infección de Heridas/microbiología , Adulto , Anciano , Técnicas de Tipificación Bacteriana , Mordeduras y Picaduras/microbiología , Capnocytophaga/genética , Femenino , Genes de ARNr , Humanos , Masculino , Persona de Mediana Edad , Reacción en Cadena de la Polimerasa , ARN Ribosómico 16S/análisis , ARN Ribosómico 16S/genética , Juego de Reactivos para Diagnóstico , Sensibilidad y Especificidad , Factores de Tiempo
9.
Clin Microbiol Infect ; 14(2): 177-80, 2008 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-18070132

RESUMEN

This study describes the development of a method for rapid preliminary species identification of bacteria from positive blood culture vials. The method yielded preliminary identification results for 496 (92%) of 541 positive blood cultures within 5 h. The method was capable of identifying the most frequently isolated bacteria (i.e., Staphylococcus aureus, coagulase-negative staphylococci, Escherichia coli, Streptococcus pneumoniae and Enterococcus spp.) to the species level. The method can be established easily, with a materials cost of 2-5 Euros per sample.


Asunto(s)
Bacteriemia/microbiología , Bacterias/clasificación , Técnicas de Tipificación Bacteriana/métodos , Algoritmos , Bacteriemia/diagnóstico , Bacterias/crecimiento & desarrollo , Bacterias/aislamiento & purificación , Técnicas de Tipificación Bacteriana/normas , Humanos , Reproducibilidad de los Resultados , Sensibilidad y Especificidad
10.
Clin Exp Immunol ; 144(2): 290-8, 2006 May.
Artículo en Inglés | MEDLINE | ID: mdl-16634803

RESUMEN

Critical interactions between the nervous system and the immune system during experimental autoimmune myasthenia gravis (EAMG) were examined in an animal model for human MG after immunization of adult female Lewis rats with Torpedo acetylcholine receptor (AChR) and complete Freund's adjuvant. Immunized rats depicted marked clinical severity of the disease. Using enzyme-linked immunospot (ELISPOT) assay and in situ hybridization techniques, immune responses in these animals were examined and showed elevated numbers of anti-AChR IgG secreting B cells and AChR reactive interferon (IFN)-gamma-secreting cells, enhanced mRNA expression of the proinflammatory cytokines IFN-gamma and tumour necrosis factor (TNF)-alpha as Th1 subset and the anti-inflammatory cytokines interleukin (IL)-4 and IL-10 as a Th2 subset, and transforming growth factor (TGF)-beta as a Th3 cytokine. Corticosterone and prostaglandin E(2) (PGE(2)) levels were measured by radioimmunoassay and illustrated increased production after immunization. Surgical denervation of the spleen reduced significantly the clinical severity of the disease, suppressed the numbers of IgG and IFN-gamma-secreting cells, down-regulated the mRNA expression for cytokines and reduced corticosterone and PGE(2) production. As controls, sham-operated rats were used and showed results as the EAMG non-denervated control rats. The data present herein, and for the first time, substantial effects of the nervous system on immune responses that may influence the outcome of EAMG. These effects were not dependent on cytokine inhibitory mediators such as prostaglandins or stress hormones. IL-10 and TGF-beta, the two potent immunosuppressive cytokines, were also suppressed, indicating a general suppression by splenic denervation. More investigations are initiated at our laboratories to understand the evident neural control over the immune system during challenges leading to the break of tolerance and development of autoimmunity, which may assist in innovative therapeutic approaches.


Asunto(s)
Desnervación/métodos , Miastenia Gravis Autoinmune Experimental/cirugía , Bazo/cirugía , Animales , Linfocitos B/inmunología , Corticosterona/sangre , Dinoprostona/inmunología , Femenino , Inmunoglobulina G/inmunología , Interferón gamma/inmunología , Interleucina-4/inmunología , Miastenia Gravis Autoinmune Experimental/inmunología , ARN Mensajero/análisis , Ratas , Ratas Endogámicas Lew , Receptores Colinérgicos/inmunología , Bazo/inervación , Linfocitos T/inmunología , Factor de Crecimiento Transformador beta/inmunología , Factor de Necrosis Tumoral alfa/inmunología
11.
Br J Cancer ; 91(4): 688-94, 2004 Aug 16.
Artículo en Inglés | MEDLINE | ID: mdl-15280930

RESUMEN

Prostate-specific antigen (PSA) is a serine protease secreted at low levels by normal luminal epithelial cells of the prostate and in significantly higher levels by prostate cancer cells. Therefore, PSA is a potential target for various immunotherapeutical approaches against prostate cancer. DNA vaccination has been investigated as immunotherapy for infectious diseases in patients and for specific treatment of cancer in certain animal models. In animal studies, we have demonstrated that vaccination with plasmid vector pVAX/PSA results in PSA-specific cellular response and protection against tumour challenge. The purpose of the trial was to evaluate the safety, feasibility and biological efficacy of pVAX/PSA vaccine in the clinic. A phase I trial of pVAX/PSA, together with cytokine granulocyte/macrophage-colony stimulating factor (GM-CSF) (Molgramostim) and IL-2 (Aldesleukin) as vaccine adjuvants, was carried out in patients with hormone-refractory prostate cancer. To evaluate the biologically active dose, the vaccine was administered during five cycles in doses of 100, 300 and 900 microg, with three patients in each cohort. Eight patients were evaluable. A PSA-specific cellular immune response, measured by IFN-gamma production against recombinant PSA protein, and a rise in anti-PSA IgG were detected in two of three patients after vaccination in the highest dose cohort. A decrease in the slope of PSA was observed in the two patients exhibiting IFN-gamma production to PSA. No adverse effects (WHO grade >2) were observed in any dose cohort. We demonstrate that DNA vaccination with a PSA-coding plasmid vector, given with GM-CSF and IL-2 to patients with prostate cancer, is safe and in doses of 900 microg the vaccine can induce cellular and humoral immune responses against PSA protein.


Asunto(s)
Adenocarcinoma/tratamiento farmacológico , Adenocarcinoma/inmunología , Vacunas contra el Cáncer , Antígeno Prostático Específico/inmunología , Neoplasias de la Próstata/tratamiento farmacológico , Neoplasias de la Próstata/inmunología , Vacunas de ADN , Adenocarcinoma/patología , Anciano , Anciano de 80 o más Años , Formación de Anticuerpos , Vacunas contra el Cáncer/administración & dosificación , Vacunas contra el Cáncer/efectos adversos , Vacunas contra el Cáncer/inmunología , Relación Dosis-Respuesta a Droga , Resistencia a Antineoplásicos , Vectores Genéticos , Factor Estimulante de Colonias de Granulocitos y Macrófagos/administración & dosificación , Humanos , Inmunidad Celular , Inmunoterapia , Interleucina-2/administración & dosificación , Masculino , Persona de Mediana Edad , Plásmidos , Neoplasias de la Próstata/patología , Resultado del Tratamiento , Vacunas de ADN/administración & dosificación , Vacunas de ADN/efectos adversos , Vacunas de ADN/inmunología
12.
Mult Scler ; 8(5): 396-404, 2002 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-12356206

RESUMEN

Multiple sclerosis (MS) is one of the leading causes of disability among young adults of Caucasian origin. One hundred and fifty years after the first description of the disease, the cause of MS remains unknown. Ironically, the few hypotheses concerning MS pathogenesis that are valid today were first proposed over a hundred years ago. However, equipped with the advanced technology of molecular biology and imaging systems, we are at present progressively uncovering dues to understanding the pathogenesis of the disease. It is dearly evident that aberrant immune responses occur in MS, and it is likely that the spectrum of cytokines produced decisively influences disease outcome. The detrimental consequences of IFN-gamma and the beneficial effects of IFN-beta treatment in MS support this hypothesis. However, there are still major gaps in our knowledge of the involvement of cytokines in MS. Numerous studies have addressed the question of cytokine levels in MS, often with conflicting results; elevated, normal and decreased levels of almost all cytokines have been reported. This scenario most probably reflects methodological dilemmas as well as the complex biology of cytokines. Here we focus on possible reasons for the discrepancies of results reported on cytokines in MS and summarize findings obtained in particular by the application of enzyme-linked immunospot (ELISPOT) assays to cytokine studies in MS.


Asunto(s)
Citocinas/metabolismo , Esclerosis Múltiple/metabolismo , Formación de Anticuerpos , Movimiento Celular , Sistema Nervioso Central/patología , Sistema Nervioso Central/fisiopatología , Citocinas/inmunología , Humanos , Leucocitos/fisiología , Esclerosis Múltiple/inmunología , Esclerosis Múltiple/patología , Esclerosis Múltiple/fisiopatología , Vaina de Mielina/patología , Oligodendroglía/patología , Investigación
13.
Neurology ; 58(3): 476-8, 2002 Feb 12.
Artículo en Inglés | MEDLINE | ID: mdl-11839856

RESUMEN

The T(H)1 vs non-T(H)1 cytokine balance in Guillain-Barré syndrome (GBS) is unknown. Using enzyme-linked immunospot (ELISPOT) assays, we observed elevated numbers of interleukin (IL)-6 and IL-10-secreting blood mononuclear cells (BMNC) during the acute phase in untreated patients, and low levels of tumor necrosis factor alpha-secreting BMNC in the recovery phase of GBS. Numbers of IL-12p70-secreting BMNC were not affected over the course of GBS. The non-T(H)1 cytokine profile observed early in GBS may explain the self-limited clinical course associated with GBS.


Asunto(s)
Síndrome de Guillain-Barré/inmunología , Interleucina-10/metabolismo , Interleucina-6/metabolismo , Leucocitos Mononucleares/inmunología , Enfermedad Aguda , Síndrome de Guillain-Barré/metabolismo , Humanos , Interleucina-12/metabolismo , Leucocitos Mononucleares/metabolismo , Células TH1/inmunología , Factor de Necrosis Tumoral alfa/metabolismo
14.
Clin Diagn Lab Immunol ; 8(6): 1248-57, 2001 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-11687471

RESUMEN

Blood monocytes as well as tissue-differentiated macrophages play a pivotal role in controlling immune reactions. Monocytes regulate the extent, nature, and duration of immune responses by secretion of cytokines. Interleukin 6 (IL-6), tumor necrosis factor alpha (TNF-alpha), IL-10, and IL-12 are of particular interest, since IL-12 shifts the immune response towards a Th1 type, facilitating the production of, e.g., TNF-alpha and IL-6, while IL-10 counteracts Th1 responses and promotes the production of Th2-related cytokines such as IL-4. A tight regulation of these four cytokines keeps the balance and decides whether Th1 or Th2 will predominate in immune reactions. Enzyme-linked immunospot (ELISPOT) assays are among the most-sensitive and -specific methods available for cytokine research. They permit ex vivo identification of individual cells actively secreting cytokines. In the present study we prepared monocytes from healthy subjects' blood and adapted ELISPOT assays to define optimal conditions to detect and enumerate monocytes secreting IL-6, TNF-alpha, IL-10, and IL-12. The optimal time for monocyte incubation was 24 h, and optimal monocyte numbers (in cells per well) were 2,000 for IL-6, 1,000 for TNF-alpha, 50,000 for IL-10, and 100,000 for enumeration of IL-12 secreting monocytes. Among healthy subjects, 10% +/- 5% of the monocytes secreted IL-6, 12% +/- 12% secreted TNF-alpha, 0.1% +/- 0.1% secreted IL-10, and 0.2% +/- 0.3% secreted IL-12 (values are means +/- standard deviations). In conclusion, ELISPOT assays constitute a valuable tool to enumerate monocytes secreting IL-6, TNF-alpha, IL-10, and IL-12 and probably to enumerate monocytes secreting other cytokines and proteins.


Asunto(s)
Citocinas/metabolismo , Monocitos/metabolismo , Adulto , Anticuerpos Monoclonales , Ensayo de Inmunoadsorción Enzimática , Femenino , Citometría de Flujo , Humanos , Inmunofenotipificación , Interleucina-10/metabolismo , Interleucina-12/metabolismo , Interleucina-6/metabolismo , Lipopolisacáridos/farmacología , Masculino , Persona de Mediana Edad , Monocitos/efectos de los fármacos , Monocitos/inmunología , Sensibilidad y Especificidad , Factor de Necrosis Tumoral alfa/metabolismo
15.
J Clin Immunol ; 21(5): 365-75, 2001 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-11720009

RESUMEN

Stroke is a common cause of death and disability in our society. Stroke is associated with changes in immune responses within the central nervous system as well as systemically. The cells contributing to such changes as well as the factors contributing to formation of the inflammatory infiltrate observed in stroke remain to be clarified. In this study, blood monocytes and corresponding mononuclear cells (MNC) were separated and examined in parallel within 4 days and 1-3 months after onset of ischemic stroke. Numbers of TNF-alpha-, IL-12-, IL-6-, and IL-10-secreting cells and of cells expressing mRNA for matrix metalloproteinase (MMP)-1, -2, -7, -9 and tissue inhibitor of MMP (TIMP)-1 were studied. The TNF-alpha-, IL-12-, and IL-6-secreting monocytes and MNC were elevated during the acute phase compared to healthy controls. Such differences were not observed when stroke patients were examined during convalescence. The IL-10-secreting monocytes did not change over the course of stroke. Levels of monocytes expressing MMP-1, MMP-7 and TIMP-1 mRNA were elevated in the acute phase of stroke patients compared to convalescence and healthy controls, as were levels of MMP-1, -2, -7, -9 and TIMP-1 mRNA expressing blood MNC. The MMP-2 and -9 activity as measured by zymography also was higher in MNC supernatants in the acute phase of stroke compared to convalescence. The high levels of proinflammatory cytokines and MMPs in blood monocytes and MNC further demonstrate the presence of systemic aberrations in the acute phase of stroke. Such changes may contribute to the influx of blood-borne cells into the ischemic lesions during the acute phase of stroke.


Asunto(s)
Citocinas/genética , Metaloproteinasas de la Matriz/genética , Monocitos/inmunología , Accidente Cerebrovascular/inmunología , Regulación hacia Arriba , Anciano , Anciano de 80 o más Años , Femenino , Estudios de Seguimiento , Perfilación de la Expresión Génica , Humanos , Interleucina-10/genética , Interleucina-12/genética , Interleucina-6/genética , Leucocitos Mononucleares/inmunología , Masculino , Metaloproteinasa 1 de la Matriz/genética , Metaloproteinasa 1 de la Matriz/metabolismo , Metaloproteinasa 2 de la Matriz/genética , Metaloproteinasa 2 de la Matriz/metabolismo , Metaloproteinasa 7 de la Matriz/genética , Metaloproteinasa 7 de la Matriz/metabolismo , Metaloproteinasa 9 de la Matriz/genética , Metaloproteinasa 9 de la Matriz/metabolismo , Persona de Mediana Edad , Inhibidor Tisular de Metaloproteinasa-1/genética , Inhibidor Tisular de Metaloproteinasa-2/genética , Factor de Necrosis Tumoral alfa/genética
16.
Clin Immunol ; 101(1): 106-12, 2001 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-11580233

RESUMEN

Whiplash injury and whiplash-associated disorders (WAD) are significant problems of modern society. Numerous attempts have been made to characterize the nature of whiplash injury. Whether the immune system is involved during the disease process is not known. In a prospective study, using enzyme-linked immunospot (ELISPOT) assays, we examined numbers of blood mononuclear cells (MNC) secreting pro- (IFN-gamma, TNF-alpha, IL-6) and anti-inflammatory (IL-10) cytokines in patients with WAD and, for reference, patients with ankle sprain and multiple sclerosis and healthy subjects. An immune response reflected by elevated numbers of TNF-alpha- and IL-10-secreting blood MNC was observed in patients with WAD examined within 3 days compared to 14 days after the whiplash injury. The patients with WAD examined within 3 days after the injury had also higher numbers of IL-6 and IL-10 secreting blood MNC compared to healthy subjects. The alterations of cytokine profiles observed in WAD were also observed in patients with ankle sprain when examined within 3 days after trauma. In contrast, there were no differences for cytokine profiles between patients with WAD examined 14 days after the whiplash injury and healthy subjects. Relatively minor trauma like WAD and ankle sprain are associated with a systemic dysregulation in numbers of cells secreting pro- as well as anti-inflammatory cytokines.


Asunto(s)
Traumatismos del Tobillo/inmunología , Interleucina-10/biosíntesis , Interleucina-6/biosíntesis , Esguinces y Distensiones/inmunología , Lesiones por Latigazo Cervical/inmunología , Adolescente , Adulto , Anciano , Células Cultivadas , Ensayo de Inmunoadsorción Enzimática , Femenino , Humanos , Interferón gamma/biosíntesis , Cinética , Recuento de Leucocitos , Leucocitos Mononucleares/inmunología , Masculino , Persona de Mediana Edad , Esclerosis Múltiple/inmunología , Estudios Prospectivos , Factor de Necrosis Tumoral alfa/biosíntesis
17.
J Clin Immunol ; 21(4): 272-7, 2001 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-11506197

RESUMEN

The human sufferings and socioeconomic burden due to whip-lash-associated disorders (WAD) are obvious but the pathogenesis of WAD is obscure. The possible involvement of the immune system during the disease process in WAD is not known. Effector molecules including chemokines and their receptors could play a role in WAD. In a prospective study using flow cytometry, we examined percentages of blood mononuclear cells (MNC) expressing the chemokines RANTES, MCP-1, MIP-1alpha, MIP-1beta, and IL-8, the chemokine receptor CCR-5, the T cell activation marker CD25, and the T cell chemoattractant IL-16 in patients with WAD and, for reference, in healthy controls. Higher percentages of RANTES-expressing blood MNC and T cells were observed in patients with WAD examined within 3 days compared to 14 days after the whiplash injury and, likewise, compared with healthy controls. The patients with WAD examined within 3 days after the accident also had higher percentages of CCR-5-expressing blood MNC, T cells, and CD45RO+ T cells compared to healthy controls. In contrast, there were no differences for any of these variables between patients with WAD examined 14 days after injury and healthy controls. In conclusion, WAD is associated with a systemic but transient dysregulation in percentages of RANTES and CCR-5 expressing MNC and T cells.


Asunto(s)
Quimiocina CCL5/sangre , Receptores CCR5/sangre , Lesiones por Latigazo Cervical/inmunología , Adulto , Estudios de Casos y Controles , Quimiocina CCL2/sangre , Quimiocina CCL3 , Quimiocina CCL4 , Quimiocinas/sangre , Femenino , Humanos , Interleucina-16/sangre , Interleucina-8/sangre , Leucocitos Mononucleares/inmunología , Activación de Linfocitos , Proteínas Inflamatorias de Macrófagos/sangre , Masculino , Persona de Mediana Edad , Estudios Prospectivos , Receptores de Quimiocina/sangre , Receptores de Interleucina-2/sangre , Subgrupos de Linfocitos T/inmunología , Factores de Tiempo
18.
J Autoimmun ; 16(4): 463-70, 2001 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-11437495

RESUMEN

Multiple sclerosis (MS) is an inflammatory, demyelinating disease of the central nervous system (CNS) characterized by blood-brain barrier (BBB) breakdown. Disruptions of BBB continuity result in an influx of activated T cells and monocytes, and could contribute to lesion formation in the CNS. Matrix metalloproteinases (MMP) are enzymes implicated in BBB disruption, and in degradation of extracellular matrix proteins and myelin components. An imbalance in levels of MMP and tissue inhibitors of MMP (TIMP) has been implicated in the pathogenesis of MS. Since monocytes form a major cell population in acute MS lesions and may facilitate their entrance into the CNS by secretion of MMP, knowledge on MMP expression by blood monocytes could be useful to improve our understanding of the pathogenesis of MS. In the present study, we examined the expression of MMP-1, -3, -7, -9, -14 and TIMP-1 mRNA by blood monocytes in patients with MS using in situ hybridization. Levels of MMP-1, -3, -7, -9 and of TIMP-1 mRNA expressing monocytes were elevated in MS compared to controls, while those of MMP-14 did not differ. We therefore conclude that MS is associated with elevated levels of MMP and TIMP expressing blood monocytes that may contribute to MS pathogenesis.


Asunto(s)
Expresión Génica , Metaloproteinasas de la Matriz/genética , Monocitos/enzimología , Esclerosis Múltiple/enzimología , Inhibidor Tisular de Metaloproteinasa-1/genética , Femenino , Humanos , Masculino , Metaloproteinasa 1 de la Matriz/genética , Metaloproteinasa 1 de la Matriz/metabolismo , Metaloproteinasa 3 de la Matriz/genética , Metaloproteinasa 3 de la Matriz/metabolismo , Metaloproteinasa 7 de la Matriz/genética , Metaloproteinasa 7 de la Matriz/metabolismo , Metaloproteinasa 9 de la Matriz/genética , Metaloproteinasa 9 de la Matriz/metabolismo , Metaloproteinasas de la Matriz/metabolismo , Metaloproteinasas de la Matriz Asociadas a la Membrana , Metaloendopeptidasas/genética , Metaloendopeptidasas/metabolismo , Persona de Mediana Edad , Esclerosis Múltiple/genética , ARN Mensajero , Inhibidor Tisular de Metaloproteinasa-1/metabolismo
19.
J Neuroimmunol ; 114(1-2): 242-52, 2001 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-11240038

RESUMEN

IL-12/IL-12 receptor (IL-12R) system orchestrates the Th1 pathway of the immune system by maintaining one of the major bridges between innate and adaptive immune responses. Here, we studied both sides of this system in patients with multiple sclerosis (MS) and in controls. MS patients displayed elevated IL-12Rbeta1 and IL-12Rbeta2 expression on PHA-activated T cells compared to healthy subjects. Higher percentages of IL-12Rbeta1 and IL-12Rbeta2 positive T cells in cerebrospinal fluid (CSF) compared to blood were observed both in MS and other neurological diseases (OND). In contrast, numbers of IL-12 secreting blood mononuclear cells (MNC) were similar in MS and controls. The functional importance of high IL-12Rbeta2 in MS was underlined by the finding that IL-12 stimulated IFN-gamma production and proliferation of PHA-activated T cells correlated with levels of IL-12Rbeta2 expression. Our data indicates a dysregulation of the IL-12/IL-12R system in MS. It is suggested that even in the absence of increased IL-12 levels, the net effect of IL-12 might be augmented in MS by elevated expression of its receptor.


Asunto(s)
Interleucina-12/inmunología , Esclerosis Múltiple/inmunología , Receptores de Interleucina/inmunología , Adulto , Linfocitos T CD4-Positivos/efectos de los fármacos , Linfocitos T CD4-Positivos/inmunología , Linfocitos T CD4-Positivos/metabolismo , Linfocitos T CD8-positivos/efectos de los fármacos , Linfocitos T CD8-positivos/inmunología , Linfocitos T CD8-positivos/metabolismo , Femenino , Citometría de Flujo , Humanos , Interferón gamma/metabolismo , Interleucina-12/líquido cefalorraquídeo , Interleucina-12/metabolismo , Masculino , Persona de Mediana Edad , Esclerosis Múltiple/líquido cefalorraquídeo , Fitohemaglutininas/farmacología , Receptores de Interleucina-12 , Células TH1/efectos de los fármacos , Células TH1/inmunología , Células TH1/metabolismo , Células Th2/efectos de los fármacos , Células Th2/inmunología , Células Th2/metabolismo
20.
J Neuroimmunol ; 112(1-2): 197-205, 2001 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-11108949

RESUMEN

Multiple sclerosis (MS) is an inflammatory demyelinating disease characterised by immune abnormalities in the central nervous system (CNS) as well as systemically. Activated, blood-borne monocytes are abundant in MS lesions, the properties of circulating monocytes are incompletely known. To delineate phenotype and levels of cytokine secreting monocytes in MS patients' blood, ELISPOT assays were used for detection and enumeration of monocytes secreting the cytokines IL-6, IL-12, TNF-alpha and IL-10. In parallel, the expression by monocytes of co-stimulatory molecules (CD40, CD80, CD86), major histocompatibility complex molecules (HLA-ABC, HLA-DR) and Fcgamma receptors (CD16, CD64) was examined by flow cytometry. Levels of blood monocytes secreting IL-6 and IL-12 were higher in patients with untreated MS and other neurological diseases (OND) compared to healthy controls, while levels of monocytes secreting TNF-alpha and IL-10 did not differ between groups. MS patients' blood monocytes also displayed elevated mean fluorescence intensity for the co-stimulatory molecule CD86, and MS patients with longer disease duration (>10 years) and higher disease severity (EDSS >3) had higher percentages of CD80 expressing monocytes compared to patients with short duration or lower severity. In conclusion, monocyte aberrations occur in MS and may change over the disease course.


Asunto(s)
Citocinas/sangre , Monocitos/inmunología , Esclerosis Múltiple/inmunología , Adulto , Anciano , Antígenos CD/sangre , Antígeno B7-1/sangre , Antígeno B7-2 , Femenino , Antígenos HLA-A/sangre , Antígenos HLA-DR/sangre , Humanos , Masculino , Glicoproteínas de Membrana/sangre , Persona de Mediana Edad , Fenotipo
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