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1.
J Antimicrob Chemother ; 75(Suppl 1): i43-i59, 2020 04 01.
Artículo en Inglés | MEDLINE | ID: mdl-32337593

RESUMEN

OBJECTIVES: To determine antibiotic susceptibility of Streptococcus pneumoniae and Haemophilus influenzae isolates from community-acquired respiratory tract infections (CA-RTIs) collected in 2015-17 from Argentina, Chile and Costa Rica. METHODS: MICs were determined by CLSI broth microdilution and susceptibility was assessed using CLSI, EUCAST (dose-specific) and pharmacokinetic/pharmacodynamic (PK/PD) breakpoints. RESULTS: A total of 170 S. pneumoniae and 218 H. influenzae isolates were collected at five centres in Argentina, Chile and Costa Rica in 2015-17. Small S. pneumoniae isolate numbers from Costa Rica (n = 2) meant that these could only be included in the penicillin susceptibility analysis; they were excluded from further country analyses. Around one-third of pneumococcal isolates from Argentina and two-thirds from Chile were non-susceptible to penicillin by CLSI oral or EUCAST low-dose IV breakpoints, but most (≥89%) were susceptible by CLSI IV or EUCAST high-dose breakpoints. Amongst pneumococci from Argentina, about 80% or more were susceptible to most other antibiotics except cefaclor (all breakpoints), cefixime (PK/PD breakpoints), cefuroxime (EUCAST breakpoints) and trimethoprim/sulfamethoxazole (CLSI and PK/PD breakpoints). S. pneumoniae isolates from Chile showed significantly lower susceptibility (P < 0.05) using CLSI breakpoints compared with those from Argentina for many of the antibiotics tested. Among isolates of H. influenzae from Latin America, more than 90% were susceptible to amoxicillin/clavulanic acid (high dose), cefixime, cefpodoxime, ceftriaxone and fluoroquinolones, irrespective of the breakpoints used. The application of different EUCAST breakpoints for low and higher doses for some of the antibiotics (amoxicillin, amoxicillin/clavulanic acid, ampicillin, penicillin, ceftriaxone, clarithromycin, erythromycin, levofloxacin and trimethoprim/sulfamethoxazole) allowed, for the first time in a SOAR study, the effect of raising the dosage on susceptibility to be quantified. CONCLUSIONS: Antibiotic susceptibility of H. influenzae isolates was generally high in the Latin American countries studied; however, susceptibility profiles varied for S. pneumoniae by country and depending on the breakpoints used, especially for cefaclor. These factors are important in decision making for empirical therapy of bacterial infections.


Asunto(s)
Haemophilus influenzae , Infecciones del Sistema Respiratorio , Antibacterianos/farmacología , Argentina/epidemiología , Chile/epidemiología , Costa Rica/epidemiología , Farmacorresistencia Bacteriana , Monitoreo Epidemiológico , Humanos , América Latina/epidemiología , Pruebas de Sensibilidad Microbiana , Infecciones del Sistema Respiratorio/epidemiología
2.
Hum Reprod ; 35(11): 2567-2578, 2020 11 01.
Artículo en Inglés | MEDLINE | ID: mdl-33011783

RESUMEN

STUDY QUESTION: What is the vaginal polymorphonuclear (PMN) spermicidal mechanism to reduce the excess of sperm? SUMMARY ANSWER: We show that PMNs are very efficient at killing sperm by a trogocytosis-dependent spermicidal activity independent of neutrophil extracellular traps (NETs). WHAT IS KNOWN ALREADY: Trogocytosis has been described as an active membrane exchange between immune cells with a regulatory purpose. Recently, trogocytosis has been reported as a mechanism which PMNs use to kill tumour cells or Trichomonas vaginalis. STUDY DESIGN, SIZE, DURATION: We used in vivo murine models and human ex vivo sperm and PMNs to investigate the early PMN-sperm response. PARTICIPANTS/MATERIALS, SETTING, METHODS: We set up a live/dead sperm detection system in the presence of PMNs to investigate in vivo and ex vivo PMN-spermicidal activity by confocal microscopy, flow cytometry and computer-assisted sperm analysis (SCA). MAIN RESULTS AND THE ROLE OF CHANCE: We revealed that PMNs are highly efficient at killing sperm by way of a NETs-independent, contact-dependent and serine proteases-dependent engulfment mechanism. PMNs 'bite' sperm and quickly reduce sperm motility (within 5 min) and viability (within 20 min) after contact. LARGE SCALE DATA: N/A. LIMITATIONS, REASONS FOR CAUTION: This study was conducted using murine models and healthy human blood PMNs; whether it is relevant to human vaginal PMNs or to cases of infertility is unknown. WIDER IMPLICATIONS OF THE FINDINGS: Vaginal PMNs attack and immobilize excess sperm in the vagina by trogocytosis because sperm are exogenous and may carry pathogens. Furthermore, this mechanism of sperm regulation has low mucosal impact and avoids an exacerbated inflammatory response that could lead to mucosal damage or infertility. STUDY FUNDING/COMPETING INTEREST(S): This work was partially supported by Ministry of Economy and Competitiveness ISCIII-FIS grants, PI16/00050, and PI19/00078, co-financed by ERDF (FEDER) Funds from the European Commission, 'A way of making Europe' and IiSGM intramural grant II-PI-MRC-2017. M.R. holds a Miguel Servet II contract (CPII14/00009). M.C.L. holds IiSGM intramural contract. There are no competing interests.


Asunto(s)
Neutrófilos , Motilidad Espermática , Animales , Europa (Continente) , Femenino , Humanos , Masculino , Ratones , Espermatozoides , Vagina
3.
Genes Immun ; 14(7): 462-9, 2013 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-23883819

RESUMEN

To reconcile immunity and reproduction, females must allow spermatozoa to survive and control the presence of commensal microbiota and sexually transmitted pathogens during ovulation. Female steroid sex hormones exert a powerful effect on the immune system, as do the hormonal changes associated with the ovarian cycle. Dendritic cells (DCs) are immunological sentinels that link innate immunity to adaptive immunity. Upon exposure to microbial invaders in tissue, they undergo a maturational process that culminates in the lymph nodes and activates T-cell-specific immune responses. Estradiol, which is highly expressed during ovulation, has an effect on the maturation of DCs, although the molecular mechanism remains elusive. We detected that estradiol regulates expression of Ikbkg in DCs and modulates nuclear factor-κb translocation to the nucleus, thus explaining the reduced DC function observed during ovulation. This change may be an adaptive mechanism to reconcile control of infection and reproductive functions.


Asunto(s)
Núcleo Celular/metabolismo , Células Dendríticas/metabolismo , Estradiol/farmacología , Quinasa I-kappa B/metabolismo , FN-kappa B/metabolismo , Transporte Activo de Núcleo Celular , Animales , Células Cultivadas , Células Dendríticas/efectos de los fármacos , Femenino , Ratones , Ratones Endogámicos BALB C , Transcripción Genética
4.
Hum Reprod ; 28(12): 3283-91, 2013 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-24065277

RESUMEN

STUDY QUESTION: What role do female sex hormones play in the antisperm immune response? SUMMARY ANSWER: We found that sperm induce a Th17 immune response and that estradiol down-regulates the antisperm Th17 response by dendritic cells. WHAT IS KNOWN ALREADY: Estradiol down-regulates the immune response to several pathogens and impairs the triggering of dendritic cell maturation by microbial products. STUDY DESIGN, SIZE, DURATION: Ex vivo and in vivo murine models of vaginal infection with sperm and Candida albicans were used to study the induction of Th17 and its hormonal regulation. PARTICIPANTS/MATERIALS, SETTING, METHODS: We analyzed the induction of Th17 cytokines and T cells in splenocytes obtained from BALB/c mice challenged with sperm and C. albicans. For the in vivo vaginal infection models, we used ovariectomized mice treated with vehicle, estradiol or progesterone, and we assessed the effect of these hormones on the immune response in the lymph nodes. MAIN RESULTS AND THE ROLE OF CHANCE: Th17 cytokines and T cells were induced by sperm antigens in both ex vivo and in vivo experiments. Estrus levels of estradiol down-regulated the Th17 response to sperm and C. albicans in vivo. LIMITATIONS, REASONS FOR CAUTION: This study was conducted using murine models; whether or not the results are applicable to humans is not known. WIDER IMPLICATIONS OF THE FINDINGS: Our results describe an adaptive mechanism that reconciles immunity and reproduction and further explains why unregulated Th17 could be linked to infertility and recurrent infections. STUDY FUNDING/COMPETING INTEREST(S): This work was supported by research grants from the Instituto de Salud Carlos III (ISCIII) (PI10/00897) and Fundación Mutua Madrileña to M.R. M.R. holds a Miguel Servet contract from the ISCIII (CP08/00228). M.A.M.-F. was supported by (ISCIII) INTRASALUD PI09/02029. We have no conflicts of interest to declare. TRIAL REGISTRATION NUMBER: Not required.


Asunto(s)
Candida albicans/inmunología , Estradiol/farmacología , Espermatozoides/inmunología , Células Th17/inmunología , Animales , Candidiasis Vulvovaginal/inmunología , Células Dendríticas/efectos de los fármacos , Células Dendríticas/inmunología , Femenino , Masculino , Ratones , Ratones Endogámicos BALB C , Células Th17/efectos de los fármacos
5.
Front Immunol ; 13: 1031941, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36569947

RESUMEN

The mucosa of the female reproductive tract must reconcile the presence of commensal microbiota and the transit of exogenous spermatozoa with the elimination of sexually transmitted pathogens. In the vagina, neutrophils are the principal cellular arm of innate immunity and constitute the first line of protection in response to infections or injury. Neutrophils are absent from the vaginal lumen during the ovulatory phase, probably to allow sperm to fertilize; however, the mechanisms that regulate neutrophil influx to the vagina in response to aggressions remain controversial. We have used mouse inseminations and infections of Neisseria gonorrhoeae, Candida albicans, Trichomonas vaginalis, and HSV-2 models. We demonstrate that neutrophil infiltration of the vaginal mucosa is distinctively contingent on the ovarian cycle phase and independent of the sperm and pathogen challenge, probably to prevent sperm from being attacked by neutrophils. Neutrophils extravasation is a multi-step cascade of events, which includes their adhesion through selectins (E, P and L) and integrins of the endothelial cells. We have discovered that cervical endothelial cells expressed selectin-E (SELE, CD62E) to favor neutrophils recruitment and estradiol down-regulated SELE expression during ovulation, which impaired neutrophil transendothelial migration and orchestrated sperm tolerance. Progesterone up-regulated SELE to restore surveillance after ovulation.


Asunto(s)
Células Endoteliales , Semen , Masculino , Femenino , Ratones , Animales , Infiltración Neutrófila , Vagina , Ciclo Menstrual
6.
Gastroenterol Hepatol ; 32(4): 294-306, 2009 Apr.
Artículo en Español | MEDLINE | ID: mdl-19395126

RESUMEN

There are several causes of damage and regeneration of the gastric epithelium (erosive gastropathy) and/or histological inflammation of the gastric mucosa (acute or chronic gastritis). After outlining the usual morphology of chronic gastritis, the authors attempt to identify the biological profile of the main pathogenic models. The first, and by far the most frequent, is the model associated with Helicobacter pylori, which, without crossing the mucosal epithelium, provokes an immune reaction. Although incapable of eradicating this bacterium, this immune reaction contributes to the inflammatory lesion provoked by H. pylori in the mucosa. The second -and much less frequent- model is that causing progressive atrophic gastritis through a humoral and cellular autoimmune mechanism. In third place are a group of models defined by a peculiar cytohistologic pattern of inflammation (granulomatous, lymphocytic or eosinophilic gastritis), suggesting similar pathogenic mechanisms for each of these rare morphological forms of gastritis. Lastly, there is a model barely fitting within the scope of this review, which is that provoking chemical gastropathies (bile reflux, NSAIDs, etc.) with minimal cellular inflammation, i.e., minimal gastritis. To aid understanding of the article, the authors provide a brief outline of the functional histology of the gastric wall and the mechanisms defending its integrity in physiological conditions.


Asunto(s)
Mucosa Gástrica/inmunología , Gastritis/inmunología , Modelos Biológicos , Enfermedad Crónica , Eosinofilia/inmunología , Mucosa Gástrica/patología , Gastritis/patología , Humanos
7.
J Reprod Immunol ; 132: 9-15, 2019 04.
Artículo en Inglés | MEDLINE | ID: mdl-30807979

RESUMEN

Female reproductive mucosa must allow allogenic sperm survival whereas at the same time, avoid pathogen infection. To preserve sperm from neutrophil attack, neutrophils disappear from the vagina during the ovulatory phase (high estradiol); although the mechanisms that regulate neutrophil influx to the vagina during insemination remain controversial. We investigated the sex hormone regulation of the neutrophil migration through the cervix during insemination and revealed that ovulatory estradiol dose fades the CXCL1 epithelial expression in the ectocervix and fornix; hence, retarding neutrophil migration and retaining them in the epithelium. These mechanisms spare sperm from neutrophil attack to preserve reproduction, but might compromise immunity. However, luteal progesterone dose promotes the CXCL1 gradient expression to restore neutrophil migration, to eliminate sperm and prevent sperm associated pathogen dissemination. Surprisingly, these mechanisms are hormone dependent and independent of the insemination. Thus, sex hormones orchestrate tolerance and immunity in the vaginal lumen by regulating neutrophil transepithelial migration in the fornix and ectocervix.


Asunto(s)
Cuello del Útero/inmunología , Quimiocina CXCL1/metabolismo , Estradiol/metabolismo , Inseminación/inmunología , Neutrófilos/inmunología , Animales , Cuello del Útero/citología , Cuello del Útero/metabolismo , Receptor alfa de Estrógeno/genética , Receptor alfa de Estrógeno/metabolismo , Femenino , Tolerancia Inmunológica , Masculino , Ratones , Ratones Noqueados , Membrana Mucosa/inmunología , Membrana Mucosa/metabolismo , Neutrófilos/metabolismo , Espermatozoides/inmunología , Espermatozoides/metabolismo , Migración Transendotelial y Transepitelial/inmunología
8.
Gastroenterol Hepatol ; 30(6): 343-50, 2007.
Artículo en Español | MEDLINE | ID: mdl-17662219

RESUMEN

The exocrine pancreas is a functionally dangerous structure since it is exposed to digestion by its most aggressive enzymes (proteases, etc) despite self-protective measures such as the synthesis of some of these enzymes in the form of inactive zymogens (trypsinogen, etc.). We review inflammatory pancreatic disease by separately analyzing its classical forms of onset: acute and chronic pancreatitis (AP and CP). There is general consensus that the initial pathogenic event in AP is intraacinar activation of trypsinogen into trypsin, followed by that of the remaining proenzymes, giving rise to an unusual model of autophagic inflammation. In contrast, consensus is lacking on the initial pathogenic event in CP (toxic-metabolic lesion, oxidative stress, ductal hypertension, etc.?), although in some cases a <> sequence due to recurrent episodes of AP seems evident. The pathogenic features shared by both forms of the disease and which justify some recent attempts to formulate an overall explanation of the pathogenesis of pancreatitis are discussed. Such an explanation would place both forms of pancreatitis within the conceptual framework of an <>.


Asunto(s)
Pancreatitis/etiología , Enfermedad Aguda , Fibrosis , Humanos , Páncreas/patología , Pancreatitis/enzimología , Pancreatitis/patología , Pancreatitis Crónica/enzimología , Pancreatitis Crónica/etiología , Pancreatitis Crónica/patología
10.
Fertil Steril ; 70(2): 366-8, 1998 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-9696238

RESUMEN

OBJECTIVE: To transfect the mouse oviduct in vivo. DESIGN: Prospective study. SETTING: Research laboratory. ANIMAL(S): Sixteen female Swiss albino mice. INTERVENTION(S): The left oviduct of 10 female mice was instilled with a liposome DNA solution. In addition, 2 control mice received liposome solution, 2 received phosphate-buffered saline solution, and 2 received no injection. MAIN OUTCOME MEASURE(S): The expression of the gene transfected (beta-galactosidase) was detected in the oviduct epithelium with the use of a routine histochemical analysis. RESULT(S): The 90% of the female mice that were transfected with liposome/beta-Gal complexes expressed the gene in the oviduct mucosa. The controls did not show beta-Gal expression. CONCLUSION(S): Cationic liposome/DNA complexes can be used for in vivo transfection of the mouse fallopian tubes. The foreign gene expression occurs in clusters of cells located along the mucosa of the isthmus and juncture regions.


Asunto(s)
Trompas Uterinas/metabolismo , Regulación Enzimológica de la Expresión Génica , Técnicas de Transferencia de Gen , beta-Galactosidasa/genética , Animales , Epitelio/metabolismo , Femenino , Liposomas , Ratones , Transfección
13.
Rev Clin Esp ; 206(5): 236-8, 2006 May.
Artículo en Español | MEDLINE | ID: mdl-16750107

RESUMEN

Under normal conditions, the digestive tube immune system is capable of establishing an effective plan of tolerance to food that is eaten daily by the human beings. However, this tolerance plan sometimes fails and in the final steps of this immunological dysreaction, other cellular elements, usual residents of the digestive mucous, such as eosinophil granulocytes, generally participate, together with the main cells of this system. This is the case, among others, of the so-called EGE-Eos. The authors summarize the spectrum of pathogenic options of these immunological food intolerances that range from those in which "all" depend on a specific IgE (GI food anaphylaxis) and those others in which "nothing" depends on this reagin (celiac sprue). An intermediate position would be occupied by the EGE-Eos in which there seems to be overlapping of immune reactions of cellular character together with a certain role of the IgE. These pathogenic pathways frequently cross a tangle of cellular and molecular events that cannot be untangled with either an image or one thousand words.


Asunto(s)
Eosinófilos/inmunología , Esofagitis Péptica/epidemiología , Esofagitis Péptica/inmunología , Hipersensibilidad a los Alimentos/epidemiología , Hipersensibilidad a los Alimentos/inmunología , Gastroenteritis/epidemiología , Gastroenteritis/inmunología , Inmunoglobulina E/inmunología , Antígenos CD4/inmunología , Humanos , Interleucinas/inmunología
14.
Mol Hum Reprod ; 6(12): 1099-105, 2000 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-11101693

RESUMEN

Mouse female genital tract was transfected in vivo using the ss-galactosidase reporter gene. To transfect the female tract, DNA/liposome complexes were injected through the infundibulum of the oviducts of adult, immature, and pseudopregnant females. Females which were in different stages of the ovarian cycle were also employed. Transfection was analysed using histochemical, immunological and molecular (Southern blotting, polymerase chain reaction and gene sequencing) procedures. The lower region of the uterine glands and the oviduct epithelium in the isthmus and juncture regions were the most conspicuous transfected areas. The greatest numbers of transfected cells were 6% in the oviduct and 9% in the uterus, meanwhile the duration of expression reached a maximum of 7 days in the oviduct and 14 days in the uterus. The hormonal stage of the genital tract epithelium directly affected transfection, as the highest number of successful transfections occurred during the meta-oestrus and pseudopregnancy stages.


Asunto(s)
Genitales Femeninos/metabolismo , Transfección , beta-Galactosidasa/genética , Factores de Edad , Animales , ADN , Epitelio/metabolismo , Estro/fisiología , Trompas Uterinas/metabolismo , Trompas Uterinas/patología , Femenino , Expresión Génica , Genitales Femeninos/patología , Masculino , Ratones , Transfección/métodos , Útero/metabolismo , Útero/patología
15.
Mycoses ; 42(1-2): 41-6, 1999 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-10394847

RESUMEN

This study investigates the epidemiology of Candida albicans strains isolated from oral and rectal swabs obtained before and after treatment with antifungal drugs in hospitalized AIDS patients. Twenty-one health care workers from the hospital unit were also studied. Samples were obtained from the oral cavity and hands. The molecular fingerprinting restriction endonuclease-digested genomic DNA technique was used. A total of 94 C. albicans strains were isolated: 76 from patients and 18 from the health care workers. Each sample was digested independently with EcoRI and HinfI restriction enzymes, electrophoresed on 0.8% agarose gels and stained with ethidium bromide. The strains were sorted into groups according to patterns. Analysis of the different restriction patterns suggests that most of the infective strains had an endogenous source, whereas the recurrences of candidosis, after antifungal therapy, could be considered as persistence or reinfection by a different strain. Our data show that horizontal transmission by strains carried by health care workers does not play an important role in the overall epidemiology of candidosis.


Asunto(s)
Infecciones Oportunistas Relacionadas con el SIDA/epidemiología , Candida albicans/genética , Candida albicans/aislamiento & purificación , Candidiasis Bucal/epidemiología , Mapeo Restrictivo , Infecciones Oportunistas Relacionadas con el SIDA/microbiología , Infecciones Oportunistas Relacionadas con el SIDA/transmisión , Candidiasis Bucal/microbiología , Candidiasis Bucal/transmisión , Enzimas de Restricción del ADN/metabolismo , ADN de Hongos/análisis , Mano/microbiología , Humanos , Transmisión de Enfermedad Infecciosa de Profesional a Paciente , Boca/microbiología , Personal de Hospital
16.
Blood ; 98(7): 2175-82, 2001 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-11568005

RESUMEN

Dendritic cells (DC) are highly specialized antigen-presenting cells that on activation by inflammatory stimuli (eg, tumor necrosis factor alpha [TNF-alpha] and interleukin-1beta [IL-1beta]) or infectious agents (eg, lipopolysaccharide [LPS]), mature and migrate into lymphoid organs. During maturation, DC acquire the capacity to prime and polarize resting naive T lymphocytes. Maturation of monocyte-derived DC (MDDC) is inhibited by the p38 mitogen-activated protein kinase (MAPK) inhibitor SB203580. This study found that in the presence of the mitogen-activated protein kinase kinase 1-extracellular signal-regulated kinase (ERK) inhibitors PD98059 or U0126, TNF-alpha- and LPS-induced phenotypic and functional maturation is enhanced. ERK pathway inhibitors increased expression of major histocompatibility complex and costimulatory molecules; loss of mannose-receptor-mediated endocytic activity; nuclear factor-kappaB DNA-binding activity; release of IL-12 p40; and allogeneic T-cell proliferation induced by LPS or TNF-alpha. Moreover, PD98059 and U0126 enhanced LPS-triggered production of IL-12 p70. In agreement with the effect of ERK inhibitors, maturation of MDDC was delayed in the presence of serum, an effect that was reversed by U0126. These results indicate that the ERK and p38 MAPK signaling pathways differentially regulate maturation of MDDC and suggest that their relative levels of activation might modulate the initial commitment of naive T-helper (Th) cells toward Th1 or Th2 subsets. The findings also suggest that maturation of MDDC might be pharmacologically modified by altering the relative levels of activation of both intracellular signaling routes.


Asunto(s)
Células Dendríticas/citología , Sistema de Señalización de MAP Quinasas/fisiología , Monocitos/citología , Transducción de Señal/fisiología , Diferenciación Celular/efectos de los fármacos , Proteínas de Unión al ADN/efectos de los fármacos , Células Dendríticas/fisiología , Interacciones Farmacológicas , Inhibidores Enzimáticos/farmacología , Humanos , Inmunofenotipificación , Quinasas de Proteína Quinasa Activadas por Mitógenos/antagonistas & inhibidores , Proteínas Quinasas Activadas por Mitógenos/farmacología , Proteínas Quinasas Activadas por Mitógenos/fisiología , Monocitos/efectos de los fármacos , Monocitos/fisiología , Factor de Necrosis Tumoral alfa/farmacología , Proteínas Quinasas p38 Activadas por Mitógenos
17.
J Biol Chem ; 275(37): 28507-12, 2000 Sep 15.
Artículo en Inglés | MEDLINE | ID: mdl-10882733

RESUMEN

The CD11a/CD18 leukocyte integrin (LFA-1; also known as alphaL/beta2) mediates leukocyte transendothelial migration during immune and inflammatory responses and participates in lymphoma metastasis. CD11a/CD18 leukocyte-restricted expression is controlled by the CD11a gene promoter, which confers tissue-specific expression to reporter genes in vitro and in vivo. DNase I protection analysis of the CD11a proximal gene promoter revealed DNA-protein interactions centered at position -110 (CD11a-110). Disruption of CD11a-110 reduced CD11a promoter activity in a cell type-specific manner, as it reduced its activity by 70% in Jurkat lymphoid cells, whereas the effect was considerably lower in K562 and HepG2 cells. Electrophoretic mobility shift assays showed evidence of cell type-specific differences in CD11a-110 binding and indicated its specific recognition by members of the polyomavirus enhancer-binding protein 2/core binding factor (CBF)/acute myeloid leukemia (AML) family of transcription factors. AML1B/CBFbeta transactivated the CD11a promoter, with AML1B/CBFbeta-mediated transactivation being completely dependent on the integrity of the CD11a-110 element. Therefore, CBF/AML factors play a role in the cell type-restricted transcription of the CD11a integrin gene through recognition of CD11a-110. The involvement of CBF/AML factors in CD11a expression raises the possibility that CD11a/CD18 expression might be deregulated in acute myeloid and B-lineage acute lymphoblastic leukemias, thus contributing to their altered adhesion and metastatic potential.


Asunto(s)
Proteínas de Unión al ADN/fisiología , Antígeno-1 Asociado a Función de Linfocito/genética , Regiones Promotoras Genéticas , Proteínas Proto-Oncogénicas , Factores de Transcripción/fisiología , Proteínas Potenciadoras de Unión a CCAAT , Línea Celular , Subunidad alfa 2 del Factor de Unión al Sitio Principal , Humanos , Factor de Transcripción AP-2 , Activación Transcripcional
18.
Gene Ther ; 8(12): 897-904, 2001 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-11426329

RESUMEN

The involvement of the vascular endothelium in a large number of diseases supports the importance of vascular-specific gene delivery for their treatment. The hereditary hemorrhagic telangiectasia type 1 is an example of a vascular inherited disease (OMIM 187300). This is an autosomal dominant vascular disorder originated by mutations in the endoglin gene and associated with frequent epistaxis, telangiectases, gastrointestinal bleedings, and arteriovenous malformations in brain, lung and liver. Here, we address for the first time the possibility of using in vivo gene transfer to target endoglin expression to the vasculature. The promoter of the endothelial gene, ICAM-2, was used to generate transgenic animals which demonstrated endothelial expression of endoglin. Next, the promoters of the human endothelial genes, endoglin and ICAM-2, were inserted upstream of the human endoglin cDNA, and the resulting constructs were systemically or locally delivered, demonstrating endoglin expression in the vessel walls of liver, lung and skin. These gene transfer experiments represent an initial step in the treatment of the hereditary hemorrhagic telangiectasia type 1 by gene therapy, and suggest that endoglin and ICAM-2 promoters can be used to deliver other genes to the endothelium specifically.


Asunto(s)
Antígenos CD/genética , Moléculas de Adhesión Celular/genética , Endotelio Vascular/metabolismo , Marcación de Gen/métodos , Regiones Promotoras Genéticas , Telangiectasia Hemorrágica Hereditaria/terapia , Molécula 1 de Adhesión Celular Vascular/genética , Animales , Western Blotting/métodos , Endoglina , Expresión Génica , Terapia Genética/métodos , Humanos , Inmunohistoquímica/métodos , Hígado/metabolismo , Pulmón/metabolismo , Ratones , Ratones Transgénicos , Receptores de Superficie Celular , Piel/metabolismo , Molécula 1 de Adhesión Celular Vascular/análisis
20.
Gastroenterol. hepatol. (Ed. impr.) ; Gastroenterol. hepatol. (Ed. impr.);32(4): 294-306, abr. 2009.
Artículo en Español | IBECS (España) | ID: ibc-60797

RESUMEN

Son numerosas las circunstancias etiológicas capaces de producir daño y regeneración del epitelio gástrico (gastropatías erosivas) y/o inflamación histológica de su mucosa (gastritis aguda o crónica). Después de recordar la morfología habitual de las llamadas gastritis crónicas, los autores han intentado identificar el perfil biológico de los principales modelos patogénicos de dichas gastritis. El primero, y con mucho el más frecuente, está asociado a la infección por Heliocobacter pylori, germen que, sin atravesar el epitelio mucoso, provoca una reacción inmune que, aunque es incapaz de eliminarlo, contribuye a la lesión inflamatoria que aquél provoca en la mucosa. El segundo modelo, mucho menos frecuente, es el responsable de una gastritis progresivamente atrófica, a través de un mecanismo autoinmune humoral y celular. En tercer lugar podemos citar un conjunto de modelos definidos por el peculiar perfil citohistológico de la inflamación (gastritis granulomatosa, linfocítica o eosinofílica), hecho que sugiere vías patogénicas similares para cada una de estas raras formas morfológicas de gastritis. Por último, hay un modelo que está situado en la frontera del tema de esta revisión, que es el que provoca algunas gastropatías químicas (reflujo biliar, toma de antiinflamatorios no esteroideos, etc.), con mínima expresión inflamatoria celular, es decir, con gastritis mínima. Para comprender mejor el contenido de este trabajo, se recuerda brevemente la histología funcional de la pared gástrica y los mecanismos defensivos de su integridad, en condiciones fisiológicas (AU)


There are several causes of damage and regeneration of the gastric epithelium (erosive gastropathy) and/or histological inflammation of the gastric mucosa (acute or chronic gastritis). After outlining the usual morphology of chronic gastritis, the authors attempt to identify the biological profile of the main pathogenic models. The first, and by far the most frequent, is the model associated with Helicobacter pylori, which, without crossing the mucosal epithelium, provokes an immune reaction. Although incapable of eradicating this bacterium, this immune reaction contributes to the inflammatory lesion provoked by H. pylori in the mucosa. The second —and much less frequent— model is that causing progressive atrophic gastritis through a humoral and cellular autoimmune mechanism. In third place are a group of models defined by a peculiar cytohistologic pattern of inflammation (granulomatous, lymphocytic or eosinophilic gastritis), suggesting similar pathogenic mechanisms for each of these rare morphological forms of gastritis. Lastly, there is a model barely fitting within the scope of this review, which is that provoking chemical gastropathies (bile reflux, NSAIDs, etc.) with minimal cellular inflammation, i.e., minimal gastritis. To aid understanding of the article, the authors provide a brief outline of the functional histology of the gastric wall and the mechanisms defending its integrity in physiological conditions (AU)


Asunto(s)
Humanos , Gastritis/fisiopatología , Mucosa Gástrica/patología , Mediadores de Inflamación/análisis , Inflamación/fisiopatología , Helicobacter pylori/patogenicidad , Infecciones por Helicobacter/fisiopatología , Enfermedades Autoinmunes/complicaciones , Antiinflamatorios/uso terapéutico
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