Project description:HIV1+ smokers develop emphysema at an earlier age and with a higher incidence than HIV1- smokers. Based on the knowledge that human alveolar macrophages (AM) are capable of producing proteases that degrade extracellular matrix components, we hypothesized that upregulation of AM matrix metalloproteinases may be associated with the emphysema of HIV1+ smokers. To test this hypothesis, microarray analysis was used to screen which MMP genes were expressed by AM isolated by bronchoalveolar lavage (BAL) of HIV1+ smokers with early emphysema. For each of the MMP genes observed to be expressed (MMP-1, -2, -7, -9, -10, -12 and -14), TaqMan PCR was used to quantify the relative expression in AM from 4 groups of individuals: HIV1 healthy nonsmokers, HIV1- healthy smokers, HIV1- smokers with early emphysema and HIV1+ smokers with early emphysema. Strikingly, while AM gene expression of MMPs was higher in HIV1- individuals with emphysema in comparison with HIV1- healthy smokers, for the majority of the MMPs (-1, -7, -9, -10, -12), AM expression from HIV1+ smokers with early emphysema was significantly higher than HIV1- smokers with early emphysema. Consistent with these observations, HIV1+ individuals with early emphysema had higher levels of epithelial lining fluid MMPs (-2, -7, -9,-12) than the 3 HIV1 groups. Interestingly, the active forms of MMP-2, -9 and -12 were detected in epithelial lining fluid from HIV1+ individuals with early emphysema, but not in any of the other groups. Considering that the substrate specificity of the upregulated AM MMPs includes collagenases, gelatinases, matrilysins and elastase, these data suggest that upregulated AM MMP genes and activation of MMP proteins may contribute to the emphysema of HIV1+ individuals who smoke. Keywords: expression study Asymptomatic HIV+ smokers with early emphysema
Project description:HIV1+ smokers develop emphysema at an earlier age and with a higher incidence than HIV1- smokers. Based on the knowledge that human alveolar macrophages (AM) are capable of producing proteases that degrade extracellular matrix components, we hypothesized that upregulation of AM matrix metalloproteinases may be associated with the emphysema of HIV1+ smokers. To test this hypothesis, microarray analysis was used to screen which MMP genes were expressed by AM isolated by bronchoalveolar lavage (BAL) of HIV1+ smokers with early emphysema. For each of the MMP genes observed to be expressed (MMP-1, -2, -7, -9, -10, -12 and -14), TaqMan PCR was used to quantify the relative expression in AM from 4 groups of individuals: HIV1 healthy nonsmokers, HIV1- healthy smokers, HIV1- smokers with early emphysema and HIV1+ smokers with early emphysema. Strikingly, while AM gene expression of MMPs was higher in HIV1- individuals with emphysema in comparison with HIV1- healthy smokers, for the majority of the MMPs (-1, -7, -9, -10, -12), AM expression from HIV1+ smokers with early emphysema was significantly higher than HIV1- smokers with early emphysema. Consistent with these observations, HIV1+ individuals with early emphysema had higher levels of epithelial lining fluid MMPs (-2, -7, -9,-12) than the 3 HIV1 groups. Interestingly, the active forms of MMP-2, -9 and -12 were detected in epithelial lining fluid from HIV1+ individuals with early emphysema, but not in any of the other groups. Considering that the substrate specificity of the upregulated AM MMPs includes collagenases, gelatinases, matrilysins and elastase, these data suggest that upregulated AM MMP genes and activation of MMP proteins may contribute to the emphysema of HIV1+ individuals who smoke. Keywords: expression study
Project description:Matrix metalloproteinase-9 (MMP-9) expression is up-regulated in alveolar macrophages (AM) of HIV1+ smokers who develop emphysema. Based on the knowledge that lung epithelial lining fluid (ELF) of HIV1+ smokers has increased levels of inflammatory cytokines compared to HIV1- smokers, we hypothesized up-regulation of lung cytokines in HIV1+ smokers may be functionally related to increased MMP-9 expression. Cytokine arrays evaluated cytokine protein levels in ELF obtained from 5 groups of individuals: HIV1‾ healthy nonsmokers, HIV1‾ healthy smokers, HIV1‾ smokers with low diffusing capacity (DLCO) , HIV1 + nonsmokers, and HIV1 + smokers with low DLCO. Among several pro-inflammatory cytokines elevated in ELF associated with smoking and HIV1+, increased levels of the Th17-related cytokine IL-23 were found in HIV1- smokers with low DLCO and HIV1+ smokers and nonsmokers. Relative IL-23 gene expression was significantly increased in AM of HIV1+ individuals, with greater expression in AM of HIV1+ smokers with low DLCO. Infection with HIV1 in vitro induced IL-23 expression in normal AM. Since AM purified by adherence contain a small number of lymphocytes, we hy-pothesized that in an AM/lymphocyte co-culture system, IL-23 would up-regulate MMP-9. IL-23 stimulation of AM/lymphocyte co-cultures in vitro induced increased MMP-9 mRNA levels and protein. AM of healthy individuals did not express IL-23 receptors (IL-23R), lung T lymphocytes express IL-23R and interact with AM in order to up-regulate MMP-9. This mechanism may contribute to the increased tissue destruction in the lungs of HIV1+ smokers and suggests that Th-17 related inflammation may play a role. IL-23 upregulates MMP-9 expression in human alveolar macrophages via a T lymphocyte/alveolar macrophage interaction, suggesting a possible role for Th-17 related inflammation in accelerated emphysema in HIV1+ smokers.
Project description:Matrix metalloproteinase-9 (MMP-9) expression is up-regulated in alveolar macrophages (AM) of HIV1+ smokers who develop emphysema. Based on the knowledge that lung epithelial lining fluid (ELF) of HIV1+ smokers has increased levels of inflammatory cytokines compared to HIV1- smokers, we hypothesized up-regulation of lung cytokines in HIV1+ smokers may be functionally related to increased MMP-9 expression. Cytokine arrays evaluated cytokine protein levels in ELF obtained from 5 groups of individuals: HIV1‾ healthy nonsmokers, HIV1‾ healthy smokers, HIV1‾ smokers with low diffusing capacity (DLCO) , HIV1 + nonsmokers, and HIV1 + smokers with low DLCO. Among several pro-inflammatory cytokines elevated in ELF associated with smoking and HIV1+, increased levels of the Th17-related cytokine IL-23 were found in HIV1- smokers with low DLCO and HIV1+ smokers and nonsmokers. Relative IL-23 gene expression was significantly increased in AM of HIV1+ individuals, with greater expression in AM of HIV1+ smokers with low DLCO. Infection with HIV1 in vitro induced IL-23 expression in normal AM. Since AM purified by adherence contain a small number of lymphocytes, we hy-pothesized that in an AM/lymphocyte co-culture system, IL-23 would up-regulate MMP-9. IL-23 stimulation of AM/lymphocyte co-cultures in vitro induced increased MMP-9 mRNA levels and protein. AM of healthy individuals did not express IL-23 receptors (IL-23R), lung T lymphocytes express IL-23R and interact with AM in order to up-regulate MMP-9. This mechanism may contribute to the increased tissue destruction in the lungs of HIV1+ smokers and suggests that Th-17 related inflammation may play a role. IL-23 upregulates MMP-9 expression in human alveolar macrophages via a T lymphocyte/alveolar macrophage interaction, suggesting a possible role for Th-17 related inflammation in accelerated emphysema in HIV1+ smokers.
Project description:Cigarette smoking is the leading cause of emphysema in the United States. Alveolar macrophages play a critical role in the inflammation-mediated remodeling of the lung parenchyma in emphysema. However, the exact gene pathways and the role of DNA methylation in moderating this pathological transformation are not known. In order to more exactly understand this process, we compared genome-wide expression and methylation signatures of alveolar macrophages isolated from heavy smokers with those isolated from non-smoking controls. We found enrichment of differential methylation in genes from immune system and inflammatory pathways as determined by standard pathway analysis. Consistent with recent findings, significant methylation changes were particularly enriched in the areas flanking CpG islands (CpG shores). Analysis of matching gene expression data demonstrated a parallel enrichment for changes in immune system and inflammatory pathways. We conclude that alveolar macrophages from the lungs of smokers demonstrate coordinated changes in DNA methylation and gene expression that link to inflammation pathways. We suggest that further studies of DNA methylation in immune and inflammation-related gene expression are needed to understand the pathogenesis of emphysema and other smoking-related diseases. Expression analysis of 13 smokers vs. 10 non-smokers on the Affymetrix Exon Array. This submission represents the expression component of the study.
Project description:Cigarette smoking is the leading cause of emphysema in the United States. Alveolar macrophages play a critical role in the inflammation-mediated remodeling of the lung parenchyma in emphysema. However, the exact gene pathways and the role of DNA methylation in moderating this pathological transformation are not known. In order to more exactly understand this process, we compared genome-wide expression and methylation signatures of alveolar macrophages isolated from heavy smokers with those isolated from non-smoking controls. We found enrichment of differential methylation in genes from immune system and inflammatory pathways as determined by standard pathway analysis. Consistent with recent findings, significant methylation changes were particularly enriched in the areas flanking CpG islands (CpG shores). Analysis of matching gene expression data demonstrated a parallel enrichment for changes in immune system and inflammatory pathways. We conclude that alveolar macrophages from the lungs of smokers demonstrate coordinated changes in DNA methylation and gene expression that link to inflammation pathways. We suggest that further studies of DNA methylation in immune and inflammation-related gene expression are needed to understand the pathogenesis of emphysema and other smoking-related diseases.
Project description:Cigarette smoking is the leading cause of the respiratory diseases collectively known as chronic obstructive pulmonary disease (COPD). While the pathogenesis of COPD is complex, there is abundant evidence that alveolar macrophages (AM) play an important role. Based on the concept that COPD is a slow-progressing disorder likely involving multiple mediators released by AM activated by cigarette smoke, the present study focuses on the identification of previously unrecognized genes that may be linked to early events in the molecular pathogenesis of COPD, as opposed to factors associated with the presence of disease. To accomplish this, microarray analysis using Affymetrix microarrays was used to carry out an unbiased survey of the differences in gene expression profiles in the AM of phenotypically normal, ~20 pack-yr smokers compared to healthy non-smokers. Although smoking did not alter the global gene expression pattern of AM, 75 genes were modulated by smoking, with 40 genes up-regulated and 35 down-regulated in the AM of smokers compared to non-smokers. Most of these genes belong to the functional categories of immune/inflammatory response, cell adhesion and extracellular matrix, proteolysis and antiproteolysis, lysosomal function, antioxidant-related, signal transduction and regulation of transcription. Of these 75 genes, 69 have not been previously recognized to be up- or down-regulated in alveolar macrophages in association with smoking or COPD, including genes coding for proteins belonging to all of the above categories, and others belonging to various functional categories or of unknown function. These observations suggest that gene expression responses of alveolar macrophages associated with the stress of cigarette smoking are more complex than previously thought, and offer a variety of new insights into the complex pathogenesis of smoking-induced lung diseases. Experiment Overall Design: 5 non smokers and 5 smokers Experiment Overall Design: Alveolar macrophages were obtained from bronchoalveolar lavage