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Las células fagocíticas (neutrófilos, eosinófilos monocitos y macrófagos) producen moléculas reactivas de oxígeno que tienen una importante acción microbicida. La generación de estas moléculas ocurre durante el fenómeno de explosión respiratoria, el cual depende de la activación de un sistema enzimático conocido como NADPH oxidasa. La importancia de este sistema se ha evidenciado gracias al estudio de la enfermedad granulomatosa crónica, pues en esta enfermedad se produce un trastorno de este complejo enzimático, lo cual altera los mecanismos microbicidas y conduce a la aparición de infecciones recurrentes. Este defecto es causado por una mutación en alguno de los genes que codifican para los componentes del sistema NADPH oxidasa. Además de estas mutaciones, se han descrito varios polimorfismos en dichos genes. Sin embargo, estos cambios nucleotídicos no se han asociado con mayor susceptibilidad a infecciones. Recientemente describimos la transición A→G en la posición –21 en el extremo 3 ́ del intrón 10 del gen NCF-2 como un posiblepolimorfismo. Puesto que esta región es necesaria para el procesamiento del pre-mRNA y en un trabajo previo se observó que la presencia de dicha transición se asociaba con la presencia de moléculas de mRNA del gen NCF-2 en las que estaba ausente el exón 11, se analizó la expresión de la proteína de 67 KDa del sistema NADPH oxidasa en individuos que tenían diferentes genotipos (A/A, G/G y A/G) en la posición –21 en el extremo 3’ del intrón 10.

Since the human immunodeficiency virus was identified as etiological agent of the acquired immunodeficiency syndrome, great advances have been accomplished in the therapeutic field leading to reduced morbidity and mortality among infected patients. However, the high mutation rate of the viral genome generates strains resistant to multiple drugs, pointing to the importance of finding new therapeutic targets. Among the HIV structural genes, the POL gene codes for three essential enzymes: reverse transcriptase, protease, and integrase; nineteen of the twenty drugs currently approved by the Food and Drug Administration to treat this viral infection, inhibit the reverse transcriptase and the protease. Although intense research has been carried out in this area during the last 10 years, HIV integrase inhibitors are not yet approved for clinical use; however the fact that presence of this enzyme is a sine qua non for a productive HIV life cycle joined to its unique properties makes it a promissory target for anti-HIV therapy. Many compounds have been claimed to inhibit integrase in vitro; however, few of them have proven to have antiviral activity and low cytotoxicity in cell systems. Diketoacid derivatives are the most promising integrase inhibitors so far reported. Initially discovered independently by Shionogi & Co. and the Merck Research Laboratories, these compounds are highly specific for the integrase with potent antiviral activity in vitro and in vivo, and low cytotoxicity in cell cultures. Some of these compounds have recently entered clinical trials. Due to the high relevance of integrase inhibitors, and specifically of diketoacid derivatives, we review the latest findings and patents in this important field of research.

It has been demonstrated that physical exercise, carried out at diverse intensities, modulates the function of different human body systems, and that it plays a major role in the immune response. Therefore, it is necessary to find out if these changes have benefic or harmful effects on the host adaptation against several pathogenic agents. The study of these physical-stress-induced changes might have a great impact on the comprehension and prevention of some diseases that involve activation of the immune system such as allergies, infections, immunodeficiencies and cancer. This article presents a review of current information concerning this area, with the purpose of providing concepts to help readers understand this biological phenomena and their implications in human health. Several immune response parameters have been studied during physical exercise, including their relationship with the stress-induced hormonal response and the profile of different hormones according to the intensity of physical activity. Also, changes in blood cell populations (lymphocytes, monocytes and neutrophils) and the behavior of cytokines and the synthesis of specific immune globulins have been assessed. This knowledge has allowed to establish a relationship between the immune and neuroendocrine systems, which might explain the various changes in the immune response and the adaptation seen in physical activity, as well as the differences found at diverse exercise intensity and frequency levels. Se ha demostrado que el ejercicio hecho a diferentes intensidades cumple una función moduladora sobre diversos sistemas, y que su acción sobre la respuesta inmune es de gran importancia. Por lo tanto, es necesario esclarecer si estos cambios constituyen efectos benéficos o perjudiciales en cuanto a las adaptaciones del hospedero frente a diversos agentes patógenos. El estudio de estos cambios inducidos por el estrés físico puede tener un impacto grande en la comprensión y prevención de algunas enfermedades que involucran la respuesta del sistema inmune como las alergias, las infecciones, las inmunodeficiencias y el cáncer. En este artículo se presenta una revisión actualizada de la información existente al respecto, con el propósito de aportar elementos que ayuden a comprender este fenómeno biológico, así como sus implicaciones para la salud humana. Se han estudiado varios parámetros de la respuesta inmune durante el ejercicio físico, entre ellos su relación con la respuesta hormonal al estrés y el comportamiento de las diferentes hormonas de acuerdo con la intensidad de aquél. También se han evaluado los cambios en las poblaciones de células sanguíneas (linfocitos, monocitos y neutrófilos) así como el comportamiento de las citoquinas y la síntesis de inmunoglobulinas específicas. Todo esto ha permitido establecer una relación entre los sistemas inmune y neuroendocrino, la cual explicaría en

Se ha demostrado que el ejercicio hecho a diferentes intensidades cumple una función moduladora sobre diversos sistemas, y que su acción sobre la respuesta inmune es de gran importancia. Por lo tanto, es necesario esclarecer si estos cambios constituyen efectos benéficos o perjudiciales en cuanto a las adaptaciones del hospedero frente a diversos agentes patógenos. El estudio de estos cambios inducidos por el estrés físico puede tener un impacto grande en la comprensión y prevención de algunas enfermedades que involucran la respuesta del sistema inmune como las alergias, las infecciones, las inmunodeficiencias y el cáncer. En este artículo se presenta una revisión actualizada de la información existente al respecto, con el propósito de aportar elementos que ayuden a comprender este fenómeno biológico, así como sus implicaciones para la salud humana. Se han estudiado varios parámetros de la respuesta inmune durante el ejercicio físico, entre ellos su relación con la respuesta hormonal al estrés y el comportamiento de las diferentes hormonas de acuerdo con la intensidad de aquél. También se han evaluado los cambios en las poblaciones de células sanguíneas (linfocitos, monocitos y neutrófilos) así como el comportamiento de las citoquinas y la síntesis de inmunoglobulinas específicas. Todo esto ha permitido establecer una relación entre los sistemas inmune y neuroendocrino, la cual explicaría en It has been demonstrated that physical exercise, carried out at diverse intensities, modulates the function of different human body systems, and that it plays a major role in the immune response. Therefore, it is necessary to find out if these changes have benefic or harmful effects on the host adaptation against several pathogenic agents. The study of these physical-stress-induced changes might have a great impact on the comprehension and prevention of some diseases that involve activation of the immune system such as allergies, infections, immunodeficiencies and cancer. This article presents a review of current information concerning this area, with the purpose of providing concepts to help readers understand this biological phenomena and their implications in human health. Several immune response parameters have been studied during physical exercise, including their relationship with the stress-induced hormonal response and the profile of different hormones according to the intensity of physical activity. Also, changes in blood cell populations (lymphocytes, monocytes and neutrophils) and the behavior of cytokines and the synthesis of specific immune globulins have been assessed. This knowledge has allowed to establish a relationship between the immune and neuroendocrine systems, which might explain the various changes in the immune response and the adaptation seen in physical activity, as well as the differences found at diverse exercise intensity and frequency levels.

Background Recurrent infection syndrome (RIS) results from repeated interactions between hosts and environmental infectious agents and is considered normal (NRIS) because of its benign evolution and positive effects in the development of normal immune responses. Abnormal RIS (ARIS) is characterized by the unusually high frequency of severe infections, either as a result of anatomical or functional abnormalities or due to primary or secondary immunodeficiencies (PIDs and SIDs, respectively). Recurrent mucocutaneous infections (MCIs) can be manifestations of RIS or ARIS and could be more frequent in primary immunodeficiencies. Similarly, etiologic agents might vary from what is observed in the general population. Methods We carried out a descriptive study to determine the prevalence of aerobic bacterial and fungal mucocutaneous infections in 452 patients with recurrent infections, using clinical records to establish immunological status associated with the presence and characteristics of the infections. Microbiological analyses from mucocutaneous lesions were used to confirm the etiology. Results We found mucocutaneous infections in 50 patients for a total of 62 episodes (bacterial or fungal infections in 38 vs. 12 patients, respectively). Mucocutaneous infections were more frequent (21.8% vs. 9.1%; OR = 2.8) and recurrent (8.7% vs. 0.2%; P= 0.000) in primary immunodeficient patients. Furthermore, those with defects in phagocytic cells presented more mucocutaneous infections (56.2%) than patients with other primary immunodeficiencies (11.3%; OR = 10.1). Conclusions Bacterial and fungal mucocutaneous infections are more frequent and severe in primary immunodeficient patients, particularly those with defective phagocytosis. Early and adequate assessment of the nature of mucocutaneous infections in ARIS should impact the ability of physicians to treat promptly, avoid complications and reduce the costs of medical assistance.

Several primary immunodeficiency diseases affecting the interleukin 12/interferon gamma (IFN-gamma) pathway have been identified, most of them characterized by recurrent and protracted infections produced by intracellular microorganisms, particularly by several species of mycobacteria. In the present study we analyzed the expression of IFN-gamma receptor (IFN-gammaR) and signal transducer and activator of transcription 1 (STAT-1) in 4 children with Mycobacterium tuberculosis infection of uncommon clinical presentation. These molecules were evaluated by flow cytometry and Western blotting in B cells transformed with Epstein-Barr virus and mutations were scanned by single-strand conformational polymorphisms and DNA sequencing. The expression of IFN-gammaR1 was normal in all 4 patients. The genetic analysis of IFN-gammaR1 and IFN-gammaR2 coding sequences did not reveal any mutation. The expression of the STAT-1 molecule was similar in patients and healthy controls; however, when the phosphorylation of this transcription factor in response to IFN-gamma activation was evaluated by Western blot, a significant lower signal was evident in one patient. These data indicate that there are no alterations in the expression or function of the IFN-gammaR chains in these patients. However, the low level of STAT-1 phosphorylation found in one of these patients might be explained by a defect in one of the molecules involved in the signal transduction pathway after IFN-gamma interacts with its receptor. In the other three patients the inability to eliminate the mycobacteria may be due to a defect in another effector mechanism of the mononuclear phagocytes.

We recently described a new variant of endemic pemphigus foliaceus (EPF) in El Bagre, Colombia, that resembles Senear-Usher syndrome and identified autoantibodies to desmoglein 1 (Dsg1), as well as to multiple known and unknown antigens including plectins, in the serum of these patients. Here, we developed a cost-effective ELISA assay capable of detecting the heterogeneous antibody population observed in these EPF patients, and useful for serum epidemiological studies. A protein extract obtained from trypsin-digested fresh bovine skin and further purified on a concanavalin A matrix was used as antigen. This extract contains an important conformational epitope (a 45 kDa tryptic fragment of the Dsg1 ectodomain), which is recognized by antibodies in serum from patients with all varieties of pemphigus foliaceus (PF), and from half of those with pemphigus vulgaris with active clinical disease. The cut-off and threshold values were normalized using human serum obtained from both endemic and non-endemic areas for PF. The efficiency of this ELISA was tested using 600 serum samples from controls and patients diagnosed with EPF, non-endemic PF and other bullous diseases. The overall sensitivity and specificity of the assay were determined to be 95% and 72%, respectively, with reproducibilities of 98% (intraassay) and 95% (interassay). Comparing the ELISA with other tests to detect EPF autoantibodies, this ELISA was the most sensitive, followed by direct immunofluorescence (DIF), indirect immunofluorescence using anti-IgG4 monoclonal antibodies and immunoprecipitation (IP), respectively. The most specific assay was IP, followed by DIF. Immunoblotting to Dsg1 exhibited both poor sensitivity and poor specificity, although plectins were well visualized. We conclude that this ELISA is an excellent tool for field serological studies, allowing testing of multiple serum samples simultaneously and for detecting, with appropriate restriction and sensitivity, the heterogeneous antibody population seen in patients with this variant of EPF. Finally, autoantibody serum levels obtained with this ELISA correlated well with the clinical activity and extent of disease in patients with El Bagre EPF.

El sindrome de hiper-IgE con infecciones recurrentes (SHIEIR) se caracteriza por infecciones de la piel y el aparato respiratorio causadas especialmente por Staphylococcus aureus y algunos hongos, infecciones que se asocian frecuentemente con dano tisular. Para explicar esta evolucion clinica se ha documentado en el SHIEIR una deficiencia en la quimiotaxis de las celulas fagociticas, pero no se ha evaluado la expresion de las moleculas de adhesion que regulan este fenomeno. Ademas, a pesar del dano tisular observado en este trastorno, no se ha estudiado la produccion de citocinas activadoras de los granulocitos ni la produccion de moleculas reactivas derivadas del oxigeno. En seis pacientes con SHIEIR se evaluo la secrecion de GM-CSF e IL-5 de las celulas mononucleares cultivadas con mitogenos y antigenos, la quimiotaxis de los granulocitos inducida por el N-formil-metionil-leucina-fenilalania (FMLP) bajo gel de agarosa, la explosion respiratoria de los granulocitos despues de la activacion con forbol-miristato-acetato (PMA) determinada por citometria de flujo y la expresion de las moleculas de superficie L-selectina y CD11b en los granulocitos activados con PMA. Ademas, se determino la modulacion ejercida sobre estas funciones de los granulocitos por el GM-CSF y los sobrenadantes de cultivos. Con respecto a los controles, los pacientes con SHIEIR presentaron una produccion normal de GMCSF y un aumento en la secrecion basal de IL-5, mientras que no existieron diferencias significativas en la quimiotaxis, la explosion respiratoria y la expresion de L-selectina y CD11b. El GM-CSF recombinante humano no modulo ninguna de las funciones evaluadas en los granulocitos de pacientes con SHIEIR, pero se observo que los sobrenadantes de cultivos de celulas mononucleares tenian la capacidad de inhibir la quimiotaxis, incrementar la explosion respiratoria y causar la liberacion de la L-selectina desde la superficie celular. Los pacientes con SHIEIR estudiados eran asintomaticos en el momento de realizar la investigacion gracias a un programa de control y terapia permanente, por lo que estos hallazgos sugieren que en este sindrome los granulocitos se activan mas facilmente en respuesta a los factores proinflamatorios y que la produccion de estas ultimas sustancias es mayor en el SHIEIR.

La infección recurrente es una causa frecuente de consulta médica y puede deberse a un grupo heterogéneo de trastornos que incrementan la susceptibilidad a los microorganismos patógenos y oportunistas, como las deficiencias inmunológicas subyacentes. Con el fin de definir un tratamiento racional oportuno y orientar el diagnóstico molecular de las inmunodeficiencias primarias, se estableció un programa para el diagnóstico fenotípico de estas enfermedades en el departamento de Antioquia (Colombia), que comprende un análisis clínico y de laboratorio de los individuos que presentan infecciones recurrentes de evolución anormal. Entre el 1 de agosto de 1994 y el 31 de julio de 2002 se hizo el diagnóstico fenotípico de inmunodeficiencia primaria en 98 pacientes. Similar a lo informado en la literatura especializada, en esta región las deficiencias predominantes de anticuerpos fueron las más frecuentes (40,8%) seguidas por las deficiencias combinadas (21,4%). Esta caracterización fenotípica ha permitido iniciar rápidamente el tratamiento adecuado y, en algunos casos, comenzar los estudios funcionales y moleculares que conduzcan al diagnóstico molecular definitivo.

Neutrophils are completely differentiated cells that die in tissues a few days after they migrate from the vascular compartment as a consequence of a rigouous apoptotic program. Many of the mediators produced during an inflammatory response delay neutrophil apoptosis allowing a more efficient removal of microorganisms but also favoring the tissue damage by reactive oxygen species (ROS) and lysosomal proteins released by neutrophils. Glucocorticoids delay the apoptosis of neutrophils but the mechanisms are not completely understood. To investigate the inhibition of glucocorticoids on neutrophil apoptosis we have used the glucose/glucose oxidase (G/GO) system as a constant source of hydrogen peroxide. When neutrophils are incubated in the presence of the G/GO system, a significant acceleration of their apoptotic response is observed. Preincubation with 10−6 M, 10−7 M, 10−8 M or 10−9 M of dexamethasone, negatively modulated the spontaneous and G/GO induced apoptosis of neutrophils. Then the G/GO system is a useful model to simulate the oxidative stress of neutrophils, and that the effect of DXM on neutrophil apoptosis depends, at least in part, on blocking the proapoptotic effect of ROS.

Background: Both clinical and laboratory evidence in exposed seronegative (ESN) individuals to human HIV-1 has suggested the existence of mechanisms of natural resistance to the infection. A 32 base-pair deletion in the gene that codes for the CCR5, which is the main coreceptor for HIV-1, confers a high degree of resistance to HIV-1 infection. However, the genotype Δ32/Δ32 is present only in 2–4% of Caucasoid ESN individuals suggesting the existence of other mechanisms of protection. Mutations different from Δ32 have also been proposed as playing a role in resistance/susceptibility to this infection. Objective: To screen for different mutations along the entire coding region of the ccr5 gene that can potentially explain the persistent seronegativity in a group of ESN individuals. Study design: Of a total of 86 individuals analyzed for Δ32 mutation by the PCR technique, 36 scored HIV seropositive (SP) and 50 were ESN. The entire group of ESN individuals was screened for other mutations in the ccr5 gene by single strand conformational polymorphism (SSCP) and DNA sequencing. Results: The frequency of the mutant allele Δ32 was 4% (4/100) for ESN individuals and 4.2% (3/72) for SP individuals. The homozygous mutant genotype (Δ32/Δ32) was found in only 2% (1/50) of ESN individuals, but in no SP individuals. The heterozygous genotype was found in 8.3% (3/36) of SP individuals and in 4% (2/50) of ESN individuals. The differences in the allelic and genotypic frequencies among the groups were not statistically significant. A comparison between the observed and the expected genotypic frequencies showed that they were significantly different for the ESN group, suggesting a protective, yet indirect effect of the mutant genotype. Conclusions: The screening of the entire coding region of the ccr5 gene in all ESN did not revealed no other mutations that could account for resistance to HIV-1 infection. Although the CCR5 molecule is the most important coreceptor for HIV-1, mutations in this gene do not account for most of the cases of natural resistance to this virus that have so far been reported.

Chronic granulomatous disease (CGD) is an uncommon inherited disorder of phagocytic cells in which a defective respiratory burst leads to severe recurrent bacterial and fungal infections. The disease is a consequence of mutations in one of the four molecules that constitute the NADPH oxidase system of electron transport, whose most critical component is an unusual flavocytochrome b localized in the plasma and specific granule membranes. Mutations in the CYBB gene (localized in the short arm of the X chromosome) encoding the beta-subunit of this flavocytochrome (gp91-phox), which is are responsible for 60-65% of all cases of CGD. In this paper, we report the molecular characterization of seven unrelated kindreds native from Colombia and Brazil with CGD caused by gp91-phox deficiency. The exons with the possible mutation were identified by single-strand conformational polymorphism (SSCP) of genomic DNA and then confirmed by DNA sequencing. In one patient we found a substitution of A to G in the penultimate nucleotide of intron 12 (IVS12-2A-->G). In four other cases, four different nonsense mutations were detected: R91X, W106X, R157X, and R290X and the other two patients showed missense substitutions: E225V and C244Y. In six of these kindreds, all mothers were carriers but one that did not present any change in the gp91-phox gene, which indicates a de novo mutation in this kindred. Then, these family-specific mutations in gp91-phox produce different structural defects that alter the expression or function of an essential component of phagocyte oxidase.

Las células fagocíticas cumplen un papel fundamental en la defensa innata del huésped contra la invasión de microorganismosL. uegod e ser fagocitados, uno de lo~ mecanismos utilizados para destruir dichos microorganismos es la producción de metabolitos intermedios del oxígeno generados a través del sistema NADPH oxidasa. Los radicales libres del oxígeno están al mismo tiempo involucrados en el daño tisular, que ocurre en muchas condiciones inflamatorias. La NADPH oxidasa es un complejo proteico conformado por varios componentes: gp91-phox y p22-phox, los cuales forman un heterodímero llamado citocromo b558q1u e se encuentra en la membrana de las células fagocíticas, y por las proteínas p47-phox, p67-phox y p40-phox que forman un complejo macromolecular localizado en el citoplasma. Durante la activación de las células fagocíticas los componentes citosólicos del sistema se translocan a la membrana y se unen al citocromo b558c'o nformandoa sí el complejo enzimático activo de la NADPH oxidasa cuya importancia biológica se ha evidenciado en las últimas cuatro décadas gracias al estudio de la enfermedad granulomatosa crónica (EGC). Ésta es una inmunodeficienciap rimariac aracterizadap or infecciones recurrentes y severas. Todos los casos de EGC reportados hasta ahora tienen que ver con una alteración en los genes que codifican las proteínas gp91-phox, p22-phox, p67-phoxy p47-phox. La p67 -phox es uno de los componentes del sistema NADPH oxidasa que más ha llamado la atención en los últimos años, pues tiene un papel fundamental en la activación del flujo de electrones desde el citoplasma a la vacuola fagocítica. En este articulo se hace una revisión acerca de lo que hasta ahora se conoce de la estructura y función de la p67-phox. Además se revisarán las diversas mutaciones identificadas en su gen, que debido a su alto grado de heterogeneidad son de gran utilidad para el entendimiento de la estructura y función del sistema NADPH oxidasa.

NADPH oxidase system is an enzymatic electron transport complex localized in the membrane of phagocytic cells. Several proteins belong to this system: A flavocytochrome b558, formed by a b chain (gp91.phox) and an a chain (p22.phox) and, at least, 3 cytosolic proteins (p47.phox, p67.phox and p40 phox). Genetic alteration in any of these proteins causes the syndrome of Chronic Granulomatous Disease (CGD). Characterization of mutations in patients with CGD has been fundamental to elucidate the structure and function of NADPH oxidase system ComponentS. Several findings make p47.phoX an interesting model to study the molecular mechanism involved in regulating the expreSSion and bioChemical function ofthis system. So far, in patients with p47.phoX defect a deletion of dinucleotide GT has been foUnd at the beginning of exon 2; most of them are homocygotic for this deletion which is probably due to recombinant events between normal p47.phoX gen and a recently described pseudogen. Any mutation found when diagnosing non.homocygotic patients (gDNA or cDNA) may represent a pseudogen change. Therefore, for precise identification of the genetic defect it is necessary to separate the normal gen from the pseudogen and to analyze individual sequences. Non.homocygotic patients posibly have a second mutation in the wild type allele different fron GT deletion. On the other hand, through site. oriented mutagenesis it is posible to modify some of the aminoacids or domains of p47.phoX, which may be essential for its function and relationship with CGD. With this method010gy it is possible to introduce changes in a gen whoSe sequence is thoroughly known and which is amplified; mutants So generated can give information concerning the structure and function of the analyzed genes, observing their effect on function. In this way the importance of a structural change on the function of a protein can be determined. El sistema NAOPH oxidasa es un complejo enzimático transportador de electrones localizado en la membrana de las células fagocíticas. Oe este sistema hacen parte varias proteínas; un flavocitocromo b558' el cual está conformado por una cadena b (gp91-phox) y una cadena a (p22-phox) y poral menos 3 proteínas citosólicas (p47-phox, p67- phox, p40-phox). Una alteración gen ética en cualquiera de estas proteínas causa el síndrome de Enfermedad Granulomatosa Crónica (EGC). La caracterizaciÓn de las mutaciones de los pacientes con EGC ha sido fundamental para dilucidar la estructura y función de los componentes del sistema NAOPH oxidasa. En el caso de la p47-phox, se han obtenido hallazgos importantes que la hacen un modelo interesante para estudiar el mecanismo molecular involucrado en regular la expresión y función bioquímica de este sistema. En los pacientes con defecto en la p47-phox investigados hasta ahora, se ha hallado una deleción del dinucleótido GT al comienzo del exón 2 , siendo la mayoría de ellos homocigóticos para esta deleción, la cual posiblemente se debe a eventos de recombinación entre el gen p47 -phox normal y un seudogen recientemente descrito. En el diagnóstico de pacientes no homocigóticos, cualquier mutación encontrada en el análisis del ONA (gONA o cONA) puede representar un cambio sufrido por el seudogen. Por lo tanto, para la identificación precisa del defecto gen ético es necesario separar el gen normal del seudogen y analizar las secuencias en forma individual. Los pacientes no homocigóticos posiblemente deben tener una segunda mutación en el alelo tipo silvestre diferente a la deleción GT. De otro lado, a través de mutagénesis sitio-dirigida se pueden modificar algunos de los aminoácidos o dominios de la p47-phox, los cuales pueden ser esenciales para su funcionamiento y su relación con la EGC. Con esta metodología, es posible introducir cambios en un gen cuya secuencia es totalmente conocida, el cual es amplificado; las mutantes así generadas pueden dar información acerca de la estructura y función de los genes analizados, observando su efecto sobre la función. De esta manera se puede determinar lo importante que puede ser un cambio estructural en la función de esta proteína.

El sistema NAOPH oxidasa es un complejo enzimático transportador de electrones localizado en la membrana de las células fagocíticas. Oe este sistema hacen parte varias proteínas; un flavocitocromo b558' el cual está conformado por una cadena b (gp91-phox) y una cadena a (p22-phox) y poral menos 3 proteínas citosólicas (p47-phox, p67- phox, p40-phox). Una alteración gen ética en cualquiera de estas proteínas causa el síndrome de Enfermedad Granulomatosa Crónica (EGC). La caracterizaciÓn de las mutaciones de los pacientes con EGC ha sido fundamental para dilucidar la estructura y función de los componentes del sistema NAOPH oxidasa. En el caso de la p47-phox, se han obtenido hallazgos importantes que la hacen un modelo interesante para estudiar el mecanismo molecular involucrado en regular la expresión y función bioquímica de este sistema. En los pacientes con defecto en la p47-phox investigados hasta ahora, se ha hallado una deleción del dinucleótido GT al comienzo del exón 2 , siendo la mayoría de ellos homocigóticos para esta deleción, la cual posiblemente se debe a eventos de recombinación entre el gen p47 -phox normal y un seudogen recientemente descrito. En el diagnóstico de pacientes no homocigóticos, cualquier mutación encontrada en el análisis del ONA (gONA o cONA) puede representar un cambio sufrido por el seudogen. Por lo tanto, para la identificación precisa del defecto gen ético es necesario separar el gen normal del seudogen y analizar las secuencias en forma individual. Los pacientes no homocigóticos posiblemente deben tener una segunda mutación en el alelo tipo silvestre diferente a la deleción GT. De otro lado, a través de mutagénesis sitio-dirigida se pueden modificar algunos de los aminoácidos o dominios de la p47-phox, los cuales pueden ser esenciales para su funcionamiento y su relación con la EGC. Con esta metodología, es posible introducir cambios en un gen cuya secuencia es totalmente conocida, el cual es amplificado; las mutantes así generadas pueden dar información acerca de la estructura y función de los genes analizados, observando su efecto sobre la función. De esta manera se puede determinar lo importante que puede ser un cambio estructural en la función de esta proteína. NADPH oxidase system is an enzymatic electron transport complex localized in the membrane of phagocytic cells. Several proteins belong to this system: A flavocytochrome b558, formed by a b chain (gp91.phox) and an a chain (p22.phox) and, at least, 3 cytosolic proteins (p47.phox, p67.phox and p40 phox). Genetic alteration in any of these proteins causes the syndrome of Chronic Granulomatous Disease (CGD). Characterization of mutations in patients with CGD has been fundamental to elucidate the structure and function of NADPH oxidase system ComponentS. Several findings make p47.phoX an interesting model to study the molecular mechanism involved in regulating the expreSSion and bioChemical function ofthis system. So far, in patients with p47.phoX defect a deletion of dinucleotide GT has been foUnd at the beginning of exon 2; most of them are homocygotic for this deletion which is probably due to recombinant events between normal p47.phoX gen and a recently described pseudogen. Any mutation found when diagnosing non.homocygotic patients (gDNA or cDNA) may represent a pseudogen change. Therefore, for precise identification of the genetic defect it is necessary to separate the normal gen from the pseudogen and to analyze individual sequences. Non.homocygotic patients posibly have a second mutation in the wild type allele different fron GT deletion. On the other hand, through site. oriented mutagenesis it is posible to modify some of the aminoacids or domains of p47.phoX, which may be essential for its function and relationship with CGD. With this method010gy it is possible to introduce changes in a gen whoSe sequence is thoroughly known and which is amplified; mutants So generated can give information concerning the structure and function of the analyzed genes, observing their effect on function. In this way the importance of a structural change on the function of a protein can be determined.

Sepsis, a syndrome of systemic response to infection is a major public health problem, because it is associated with high morbidity and mortality. Among the genes shown to be associated with this syndrome, there is one which encodes for caspase-12 (csp-12). Within this gene, the single nucleotide polymorphism 125T>C located in exon 4, which predicts a long form of the protein, has been associated with severe sepsis and increased related mortality. On the other hand, higher frequency of allele L has been reported in African American populations. The present study evaluated the csp-12 polymorphism 125T>C in 128 individuals: 81 patients with sepsis, 23 healthy African Colombian subjects and 24 healthy individuals from Medellin-Colombia. We found 121 individuals homozygous S/S (csp-12 short) in these three populations and 7 heterozygotes S/L, discriminated as follows: 3 septic patients, 3 African Colombians and 1 healthy subject from Medellin. This preliminary data suggest that the csp-12L allele is present in the Colombian population, both in African Colombians and Mestizo individuals (either septic patients or healthy individuals).Therefore, more comprehensive studies should be performed to better understand the genetic basis of the immune response of patients with sepsis in order to design more rational and personalized therapies to prevent this syndrome. RESUMEN: La sepsis, un síndrome de respuesta sistémica a la infección, es un problema de salud pública asociado a alta morbilidad y mortalidad alrededor del mundo. Entre los múltiples genes asociados a esta enfermedad se encuentra el gen que codifica para la caspasa-12 (csp-12), en el cual se ha identificado un polimorfismo de un sólo nucleótido (125T>C) en el exón 4 que predice una forma larga (L) de la proteína, que a su vez se ha asociado con riesgo de sepsis grave y alta mortalidad. Además, se ha demostrado que la frecuencia del alelo L es mucho mayor en poblaciones afroamericanas. Este estudio evalúa la presencia ó el polimorfismo 125T® C de la csp-12 en 128 individuos: 81 pacientes de Medellín con diagnóstico de sepsis, 23 individuos sanos de una población afroamericana del Chocó y 24 individuos sanos provenientes de Medellín. En las tres poblaciones se encontraron 121 individuos homocigotos S/S (csp-12 corta) y 7 heterocigotos S/L discriminados así: 3 pacientes con diagnóstico de sepsis, 3 individuos afroamericanos y 1 de la población sana de Medellín. Nuestros resultados muestran que, a pesar de ser una muestra pequeña, en nuestra población existe el alelo L, encontrándose en mayor frecuencia en individuos afroamericanos y en una menor proporción en los mestizos, tanto pacientes como en los individuos sanos. Esto indica que la población afroamericana de Colombia podría tener mayor susceptibilidad a sepsis grave que las poblaciones mestizas, las cuales, se ha demostrado, son producto de mezcla europea, amerindia y africana, ésta última en una baja proporción. Por lo tanto, se deben efectuar estudios más amplios para un mejor entendimiento de las bases genéticas de la respuesta inmune de pacientes con sepsis, con el fin de diseñar terapias más racionales y personalizadas para prevenir este síndrome.

The phagocytic NADPH-oxidase is a multiprotein system activated during the inflammatory response to produce superoxide anion (O2−), which is the substrate for formation of additional reactive oxygen species (ROS). The importance of this system for innate immunity is established by chronic granulomatous disease (CGD), a primary immunodeficiency caused by defects in the NADPH oxidase. In this review, we present and discuss recent knowledge about p40phox, the last NADPH oxidase component to be identified. Furthermore, its interaction with cellular pathways outside of the NADPH oxidase is discussed. Described in this review is evidence that p40phox participates in NADPH oxidase dynamics within cells, what is known about its role in the oxidase, the possibility that p40phox participates in non-NADPH oxidase processes in phagocytic and non-phagocytic cells and whether p40phox could mediate a similar function in other NADPH oxidases. An improved understanding of p40phox should provide new insights about NADPH oxidase, the physiology of phagocytic cells and the innate immune system.

RESUMEN: El sistema NADPH oxidasa de las células fagocíticas es un complejo enzimático encargado de producir anión superóxido durante la respuesta contra los microorganismos. Mutaciones en los genes que codifican para las proteínas de este sistema son responsables de la Enfermedad Granulomatosa Crónica (EGC) que es una inmunodeficiencia primaria caracterizada por la presencia de infecciones recurrentes debidas a un grupo específico de microorganismos, principalmente oportunistas. Actualmente el tratamiento para la mayoría de los pacientes con EGC está dirigido a la prevención o al control de los procesos infecciosos, pero no a la curación de la enfermedad. El tratamiento curativo consiste en el trasplante alogénico de médula ósea (TMO); sin embargo, este método enfrenta dificultades como la incompatibilidad de HLA, la inmunosupresión debida a las condiciones mieloablativas necesarias para el trasplante y el riesgo de desarrollar la enfermedad injerto contra hospedero. Como una alternativa al TMO, ha surgido la terapia génica ex vivo en células progenitoras hematopoyéticas. Las características genéticas de la EGC le han permitido convertirse en un modelo para el estudio de la terapia génica ex vivo. En este artículo se describen y analizan los resultados que hasta la fecha se han obtenido en el campo de la terapia génica aplicada a la EGC. ABSTRACT: Reactive oxygen species (ROS) production by phagocytes is an important mechanism to kill invading microorganisms. Neutrophils from individuals with chronic granulomatous disease (CGD) do not produce ROS, thereby rendering these individuals more susceptible to infection. CGD results from mutations in the genes encoding essential subunits of respiratory burst NADPH oxidase, the enzyme complex necessary for the production of these reactive molecules. The absence of phagocyte ROS results in recurrent fungal and bacterial infections and inflammatory granulomas, associated with significant morbidity and mortality. Currently, the curative treatment is the allogenic bone marrow transplant (BMT); nevertheless, this therapy has some disadvantages including the HLA incompatibility, the immunosupression due to the myeloablative conditions necessary for the transplant and the high risk to develop graft vs. host disease. As an alternative to BMT the ex vivo gene therapy in hematopoietic stem cells has been intensely studied. Although this option could be the most appropriate treatment, it can give rise to other kinds of adverse effects. The genetic features of CGD have made it a very attractive candidate to be cured with gene therapy. This review summarizes and discusses the current advances about gene therapy and its application to CGD.

The NADPH oxidase system plays a central role in the antimicrobial activity of phagocytes. This system is initiated by the translocation of cytosolic proteins p67phox, p47phox and p40phox to be in close contact with membrane flavocytochrome b558. This event begins the electron transfer from cytosolic NADPH to molecular oxygen to produce superoxide anions. Herein, a functional analysis is presented of p67phox polymorphisms identified from healthy humans. Mutations were generated in the p67phox cDNA by site-directed mutagenesis and then transiently expressed in COS7 cells that also expressed gp91phox, p22phox, and p47phox from stable transgenes. The changes Va1166lle, Pro329Ser and His389Gln correspond to possible polymorphisms identified in healthy individuals revealed a functional activity similar to COSphox cells transiently transfected with WT p67phox; therefore, these modifications are not associated with genetic deficiencies in NADPH oxidase. In conclusion, the COSphox system represents an easily transfectable model for analysis of NADPH oxidase function in intact cells. The analysis of mutant derivatives of p67phox provides insight into molecular mechanisms by which this subunit regulates the NADPH oxidase.

Background: Apoptosis, also known as programmed cell death, has been reported not only as a pathogenic mechanism, but also as a mechanism of resistance and control of a variety of infections. Particularly during HIV-1 infection, apoptosis is the main mechanism by which infected and uninfected CD4+ lymphocytes are eliminated. However, apoptosis as a mechanism of natural resistance to HIV infection has this far not been explored. Objective: To determine whether apoptosis could explain, at least in part, the natural resistance to HIV infection observed in some exposed but uninfected individuals (ESN). Results: Our data shows that peripheral blood monocytes in the ESN group has a predisposition to undergo spontaneous apoptosis, as well as apoptosis induced by HIV infection in vitro, compared with monocyte population from the control group at low risk of HIV infection. Conclusions: These findings suggest that, in some ESN individuals, monocytes could play an important role in the control of HIV infection by undergoing apoptosis. However, since the variability among individuals is large, studies with larger cohorts focusing in monocyte apoptosis as pathogenic mechanisms are required.

Hyper-IgE syndrome (HIES) is a rare multisystem disorder characterized by increased susceptibility to infections associated with heterogeneous immunologic and non-immunologic abnormalities. Most patients consistently exhibit defective antigen-induced-T cell activation, that could be partly due to altered costimulation involving accessory molecules; however, the expression of these molecules has never been documented in HIES. Therefore, we investigated the expression of CD11a, CD28, CD40, CD54, CD80, CD86, and CD154 in peripheral blood mononuclear cells from six patients and six healthy controls by flow cytometry after autologous and mixed allogeneic reactions. Only the allogeneic stimuli induced significant proliferative responses and interleukin 2 and interferon gamma production in both groups. Most accessory, molecules showed similar expression between patients and controls with the exception of CD54, being expressed at lower levels in HIES patients regardless of the type of stimulus used. Decreased expression of CD54 could partly explain the deficient T cell activation to specific recall antigens in HIES patients, and might be responsible for their higher susceptibility to infections with defined types of microorganisms.

The hyper-IgE syndrome with recurrent infections (HIESRI) is characterized by skin and respiratory infections due to Staphylococcus aureus and several fungi infections which are frequently associated with tissue damage. A deficiency in the chemotaxis of phagocytic cells has been documented to explain these findings; however, the expression of adhesion molecules, the secretion of cytokines that activate granulocytes and the production of oxygen reactive molecules have not been evaluated in HIESRI. Six HIESRI patients were evaluated for the following parameters: (1) secretion of GM-CSF and IL-5 by mitogen and antigen-activated mononuclear cells, (2) the chemotactic response of FMLP-activated granulocytes, (3) the respiratory burst of PMA-activated granulocytes, and (4) the expression of L-selectin and CD11b in PMA-activated granulocytes. Human recombinant GM-CSF and culture supernatants were evaluated for capacity to modulate granulocytic function. Compared to controls, HIESRI patients showed a normal production of GM-CSF and an increase in the basal secretion of IL-5. No significant differences were observed for chemotaxis, respiratory burst or L-selectin and CD11b expression. The GM-CSF did not modulate these functions in granulocytes from HIESRI patients, but culture supernatants applied to granulocytes inhibited chemotaxis, increased respiratory burst and caused the shedding of L-selectin from the granulocyte surface. The 6 HIESRI patients were nonsymptomatic during the time of this research due to a program of continued treatment; findings suggest that granulocytes are activated more easily in response to proinflammatory factors and that production of these factors is higher in HIESRI.

In Colombia, most cases of human cutaneous leishmaniasis are caused by Leishmania (Viannia) panamensis. Interestingly, up to 30% of the exposed population do not suffer from clinical leishmaniasis although it is likely that they are continuously infected with Leishmania parasites. Since it is believed that the induction of efficient Th1 immune responses protects against Leishmania infections both in humans and in animal models, we determined if endemically exposed asymptomatics showed stronger Leishmania-specific Th1 immune responses than patients with active localized cutaneous leishmaniasis (LCL). We found that Montenegro skin test responses were slightly higher among asymptomatic individuals compared to patients suffering from LCL. However, PBMC from patients with LCL showed similar Leishmania-specific proliferative responses compared to PBMC from asymptomatic individuals. Furthermore, PBMC from both groups also secreted similar amounts of IFN-gamma, IL-12p40 and IL-10 after in vitro exposure to L. panamensis. No IL-4 was detected in the supernatants. Taken together our results suggest that lack of LCL development in endemically exposed asymptomatics cannot be explained by stronger systemic anti-Leishmania Th1 immune responses or decreased Th2 responses in these individuals in comparison to individuals who develop LCL. It may be possible that other mechanisms are responsible for resistance to cutaneous leishmaniasis in Colombia in endemically exposed asymptomatics.

In the present study, we explored whether mitogenic stimulation of dexamethasone (DXM)- and cyclosporine A (CsA)-immunosuppressed peripheral blood lymphocytes (PBML) induced apoptosis or necrosis and their relation with the production of reactive oxygen intermediates. Our results indicate that both phenomena can occur in these cells and that antioxidants such as N -acetyl cysteine (NAC) and ascorbic acid (AA) can modulate them. However, DXM-induced apoptosis was only partially inhibited by NAC and AA, suggesting that DXM-treated PBMC had an additional apoptotic pathway independent of ROIs. Furthermore, we observed that the inhibition of apoptosis by antioxidants correlated with an increased cell proliferation, suggesting that the immunomodulation of both DXM and CsA may be related to induction of apoptosis. The ability to differentially modulate apoptosis and necrosis by antioxidants opens new possibilities in the management of immunosuppressive therapy, since the inhibition of necrosis may avoid inflammation and the tissue damage associated with immunosupressors.

El síndrome de hiperinmunoglobulinemia E(SHIE) es una Inmunodeficiencia Primaria (IOP) de origen desconocido, cuya fisiopatología no ha sido -esclarecida. Sus manifestaciones comienzan en las primeras semanas de vida. Es característico en su expresión clínica el desarrollo de un síndrome de infección recurrente patológica, con neumopatía supurativa y neumatoceles perennes principalmente producidos por Staphylococcusaureus; se encuentran niveles séricos muy elevados de IgE. En nuestras investigaciones sobre la patogénesis del ?HIE, la hipótesis propone varias alteraciones como causas importantes para su presentación: Trastornos en la activación y generación de memoria de los linfocitos T, posiblemente debida a una expresión e interacción inadecuadas de las moléculas de superficie involucradas en este fenómeno (CO40L, CO80, CO86, CTLA-4); un patrón de citoquinas diferente, con producción incrementada de IL-13 que sería la responsable del exceso de síntesis de la IgE y del factor estimulante de colonias de granulocitos y monolitos G M-CSF (G M-CS F= Granulocyte-Monocyte Colony Stimulating Factor) el cual modularía la alteración en la función de las células fagocíticas.

RESUMEN El papel de las subpoblaciones de células TCD4+, Th1 y Th2, ha sido bien estudiado en la infección por Leishmania major en el modelo murino experimental. Las cepas singénicas de ratones que desarrollan el fenotipo Th1 (células que secretan principalmente IL-2, IFN-ƴ y TNF-β) son resistentes a la infección por este protozoo. En contraste, las que desarrollan el fenotipo Th2 (células que secretan principalmente IL-4, IL-5, IL-6, IL-10 e IL-13) son susceptibles a ella. Los estudios recientes indican que la IL-4 es una señal esencial en la estimulación primaria y maduración de las células Th2, mientras que IL-12 permite la maduración de las células Th1. Adicionalmente, IL.4 e IFN-ƴ ejercen efectos reguladores opuestos sobre las células Th1 y Th2 respectivamente. Por otra parte, varios estudios han establecido claramente que la subpoblación de linfocitos TCD8+ también contribuye a la resolución de la enfermedad y la resistencia contra la reinfección en leishmaniosis cutánea. En los humanos, aunque la respuesta inmune dirigida contra el parásito es menos polarizada que en el ratón, se ha evidenciado una clara tendencia hacia la producción del fenotipo Th1 en las formas menos severas de la enfermedad. La identificación de subpoblaciones de células T humanas que se correlacionen con susceptibilidad o resistencia a la infección podría ayudar al desarrollo de ensayos in vitro para identificar antígenos de Leishmania que estimulen una respuesta inmune protectora y que puedan evaluarse como candidatos en el desarrollo de una vacuna capaz de controlar la infección. ABSTRACT The role of TCD4+ cell subsets, Th1 and Th2, has been studied in the infection by Leishmania major in the murine model. The development of the Th1 phenotype in inbred strains of mice (cellsthat mainly secrete IL.2, IFN- ƴ and TNF- β) are associated with resistance to L. major infection. In contrast, Th2 phenotype (cells that mainlysecrete IL-4, IL-5, IL-6, IL-10 and IL-13) are associated with susceptibility to the infection. Recent data suggest than IL-4 appears to be essential for the priming and maturation of Th2 cells while IL-12 enhances the maturation of Th1 cells. In addition, IL-4 and IFN- ƴ exert opposite regulatory effects on Th1 and Th2 cells, respectively. Recent findings have clearly established that the CD8+ T cell subpopulations also contribute to the resolution of the disease and resistance against infection. In humans, although the specific immune response against the parasiteis less polarized than in mice, there is a clear tendency to the development of the Th1 phenotypein the mild forms of cutaneous infection.

RESUMEN El sistema NAOPH oxidasa es un complejo enzimático transportador de electrones localizado en la membrana de las células fagocíticas. De este sistema hacen parte varias proteínas; un flavocitocromo b558, el cual está conformado por una cadena b (gp91-phox) y una cadena a (p22-phox) y por al menos 3 proteínas citosólicas (p47-phox, p67-phox, p40-phox). Una alteración genética en cualquiera de estas proteínas causa el síndrome de Enfermedad Granulomatosa Crónica (EGC). La caracterización de las mutaciones de los pacientes con EGC ha sido fundamental para dilucidar la estructura y función de los componentes del sistema NADPH oxidasa. En el caso de la p47-phox, se han obtenido hallazgos importantes que la hacen un modelo interesante para estudiar el mecanismo molecular involucrado en regular la expresión y función bioquímica de este sistema. En los pacientes con defecto en la p47-phox investigados hasta ahora, se ha hallado una deleción del dinucleótido GT al comienzo del exón 2, siendo la mayoría de ellos homocigóticos para esta deleción, la cual posiblemente se debe a eventos de recombinación entre el gen p47-phox normal y un seudogen recientemente descrito. En el diagnóstico de pacientes no homocigóticos, cualquier mutación encontrada en el análisis del DNA (gDNA o cDNA) puede representar un cambio sufrido por el seudogen. Por lo tanto, para la identificación precisa del defecto genético es necesario separar el gen normal del seudogen y analizar las secuencias en forma individual. Los pacientes no homocigóticos posiblemente deben tener una segunda mutación en el alelo tipo silvestre diferente a la deleción GT. De otro lado, a través de mutagénesis sitio-dirigida se pueden modificar algunos de los aminoácidos o dominios de la p47-phox, los cuales pueden ser esenciales para su funcionamiento y su relación con la EGC. Con esta metodología, es posible introducir cambios en un gen cuya secuencia es totalmente conocida, el cual es amplificado; las mutantes así generadas pueden dar información acerca de la estructura y función de los genes analizados, observando su efecto sobre la función. De esta manera se puede determinar lo importante que puede ser un cambio estructural en la función de esta proteína. ABSTRACT NADPH oxidase system is an enzymatic electron transport complex localized in the membrane ofphagocytic cells. Several proteins belong to this system: A flavocytochrome b558, formed by a b chain (gp91-phox) and an a chain (p22.phox) and, at least, 3 cytosolic proteins (p47-phox, p67-phox and p40 phox). Genetic alteration in any of these proteins causes the syndrome of Chronic Granulomatous Disease (CGD). Characterization of mutations inpatients with CGD has been fundamental to elucidate the structure and function of NADPH oxidase system components. Several findings make p47-phoX an interesting model to study the molecular mechanism involved in regulating the expression and biochemical function of this system. So far, in patients with p47-phoX defect a deletion of dinucleotide GT has been found at the beginning of exon 2; most of them are homocygotic for this deletion which is probably due to recombinant events between normal p47-phoX gen and a recently described pseudogen. Any mutation found when diagnosing non-homocygotic patients (gDNA or cDNA) may represent a pseudogen change. Therefore, for precise identification of the genetic defect it is necessary to separate the normal gen from the pseudogen and to analyze individual sequences. Non-homocygotic patients posibly have a second mutation in the wild type allele different fron GT deletion. On the other hand, through siteoriented mutagenesis it is posible to modify some of the aminoacids or domains of p47-phoX, which may be essential for its function and relationship with CGD. With this methodology it is posible to introduce changes in a gen whose sequence is thoroughly known and which is amplified; mutants so generated can give information concerning the structure and function of the analyzed genes, observing their effect on function. In this way the importance of a structural change on the function of a protein can be determined. COL0012426

La periodontitis juvenil localizada (PJL) se caracteriza por presentar una pérdida rápida de la inserción del tejido conectivo y el hueso alveolar alrededor de los primeros molares e incisivos de la dentición permanente. Esta Investigación se realizó para establecer una relación entre el comportamiento In vitro de los polimorfonucleares neutrófilos (PMN) y los diferentes tipos clínicos de la enfermedad. Se estudiaron 21 pacientes con PJL clasificados en tres grupos: incipiente, moderada y avanzada. Antes de que los pacientes recibieran algún tipo de tratamiento odontológico, se les aislaron los neutrófilos y se estudió, In vitro, la quimiotaxis bajo agarosa y la actividad metabólica mediante la quimioluminiscencia dependiente de luminol (QLDL). Las mismas pruebas fueron practicadas en forma paralela a un grupo de individuos sanos como controles. Los pacientes con PJL avanzada tuvieron una disrninución significativa de la quimiotaxis (p=0.023). Su índice quimiotáctico fue de 9.4 ± 1.01 mientras el de los controles fue 11.9 ± 0.33. De otro lado, la QLDL de los PMN estimulados con forbol miristato acetato (PMA) fue normal en todos los grupos, comparados con los controles; en contraste la estimulación de los PMN con zymosan opsonizado, evidenció una actividad metabólica significativamente disminuida en los pacientes con PJL incipiente y avanzada: el promedio de producción de energía lumínica en cpm para el grupo con PJL avanzada fue 703376± 74510 y para el de PJL incipiente fue 737000± 168610; en contraste en el grupo control fue 916597±47418 (p=0.012). Estos hallazgos revelan que los pacientes con PJL conforman un grupo heterogéneo en cuanto a la función de los PMN. Para esclarecer la respuesta de los PMN en cada tipo de PJL, se hace necesario estudiar la vinculación entre los componentes genéticos, el medio ambiente y los fenotipos clínicos de la enfermedad.