Background: The heterodimer interleukin (IL)-17A/F is elevated in the lungs in chronic respiratory disease such as severe asthma, along with the pro-inflammatory cytokine tumor necrosis factor... Show moreBackground: The heterodimer interleukin (IL)-17A/F is elevated in the lungs in chronic respiratory disease such as severe asthma, along with the pro-inflammatory cytokine tumor necrosis factor-alpha (TNF-alpha). Although IL-17A/F and TNF-alpha are known to functionally cooperate to exacerbate airway inflammation, proteins altered by their interaction in the lungs are not fully elucidated. Results: We used Slow Off-rate Modified Aptamer-based proteomic array to identify proteins that are uniquely and/or synergistically enhanced by concurrent stimulation with IL-17A/F and TNF-alpha in human bronchial epithelial cells (HBEC). The abundance of 38 proteins was significantly enhanced by the combination of IL-17A/F and TNF-alpha, compared to either cytokine alone. Four out of seven proteins that were increased > 2-fold were those that promote neutrophil migration; host defence peptides (HDP; Lipocalin-2 (LCN-2) and Elafin) and chemokines (IL-8, GRO alpha). We independently confirmed the synergistic increase of these four proteins by western blots and ELISA. We also functionally confirmed that factors secreted by HBEC stimulated with the combination of IL-17A/F and TNF-alpha uniquely enhances neutrophil migration. We further showed that PI3K and PKC pathways selectively control IL-17A/F + TNF-alpha-mediated synergistic production of HDPs LCN-2 and Elafin, but not chemokines IL-8 and GRO alpha. Using a murine model of airway inflammation, we demonstrated enhancement of IL-17A/F, TNF-alpha, LCN-2 and neutrophil chemokine KC in the lungs, thus corroborating our findings in-vivo. Conclusion: This study identifies proteins and signaling mediated by concurrent IL-17A/F and TNF-alpha exposure in the lungs, relevant to respiratory diseases characterized by chronic inflammation, especially neutrophilic airway inflammation such as severe asthma. Show less
Altieri, A.; Piyadasa, H.; Hemshekhar, M.; Osawa, N.; Recksiedler, B.; Spicer, V.; ... ; Mookherjee, N. 2022
Background: The heterodimer interleukin (IL)-17A/F is elevated in the lungs in chronic respiratory disease such as severe asthma, along with the pro-inflammatory cytokine tumor necrosis factor... Show moreBackground: The heterodimer interleukin (IL)-17A/F is elevated in the lungs in chronic respiratory disease such as severe asthma, along with the pro-inflammatory cytokine tumor necrosis factor-alpha (TNF-alpha). Although IL-17A/F and TNF-alpha are known to functionally cooperate to exacerbate airway inflammation, proteins altered by their interaction in the lungs are not fully elucidated.Results: We used Slow Off-rate Modified Aptamer-based proteomic array to identify proteins that are uniquely and/or synergistically enhanced by concurrent stimulation with IL-17A/F and TNF-alpha in human bronchial epithelial cells (HBEC). The abundance of 38 proteins was significantly enhanced by the combination of IL-17A/F and TNF-alpha, compared to either cytokine alone. Four out of seven proteins that were increased > 2-fold were those that promote neutrophil migration; host defence peptides (HDP; Lipocalin-2 (LCN-2) and Elafin) and chemokines (IL-8, GRO alpha). We independently confirmed the synergistic increase of these four proteins by western blots and ELISA. We also functionally confirmed that factors secreted by HBEC stimulated with the combination of IL-17A/F and TNF-alpha uniquely enhances neutrophil migration. We further showed that PI3K and PKC pathways selectively control IL-17A/F + TNF-alpha-mediated synergistic production of HDPs LCN-2 and Elafin, but not chemokines IL-8 and GRO alpha. Using a murine model of airway inflammation, we demonstrated enhancement of IL-17A/F, TNF-alpha, LCN-2 and neutrophil chemokine KC in the lungs, thus corroborating our findings in-vivo.Conclusion: This study identifies proteins and signaling mediated by concurrent IL-17A/F and TNF-alpha exposure in the lungs, relevant to respiratory diseases characterized by chronic inflammation, especially neutrophilic airway inflammation such as severe asthma. Show less
Meier, N.R.; Battegay, M.; Ottenhoff, T.H.M.; Furrer, H.; Nemeth, J.; Ritz, N.; Swiss HIV Cohort Study 2021
Background: In individuals living with HIV infection the development of tuberculosis (TB) is associated with rapid progression from asymptomatic TB infection to active TB disease. Sputum-based... Show moreBackground: In individuals living with HIV infection the development of tuberculosis (TB) is associated with rapid progression from asymptomatic TB infection to active TB disease. Sputum-based diagnostic tests for TB have low sensitivity in minimal and subclinical TB precluding early diagnosis. The immune response to novel Mycobacterium tuberculosis in-vivo expressed and latency associated antigens may help to measure the early stages of infection and disease progression and thereby improve early diagnosis of active TB disease.Methods: Serial prospectively sampled cryopreserved lymphocytes from patients of the Swiss HIV Cohort Study developing TB disease ("cases") and matched patients with no TB disease ("controls") were stimulated with 10 novel Mycobacterium tuberculosis antigens. Cytokine concentrations were measured in cases and controls at four time points prior to diagnosis of TB: T1-T4 with T4 being the closest time point to diagnosis.Results: 50 samples from nine cases and nine controls were included. Median CD4 cell count at T4 was 289/ul for the TB-group and 456/ul for the control group. Viral loads were suppressed in both groups. At T4 Rv2431c-induced and Rv3614/15c-induced interferon gamma-induced protein (IP)-10 responses and Rv2031c-induced and Rv2346/Rv2347c-induced tumor necrosis factor (TNF)-alpha responses were significantly higher in cases compared to controls (p < 0.004). At T3 - being up to 2 years prior to TB diagnosis - Rv2031c-induced TNF-alpha was significantly higher in cases compared to controls (p < 0.004). Area under the receiver operating characteristics (AUROC) curves resulted in an AUC > 0.92 for all four antigen-cytokine pairs.Conclusion: The in vitro Mycobacterium tuberculosis-specific immune response in HIV-infected individuals that progress toward developing TB disease is different from those in HIV-infected individuals that do not progress to developing TB. These differences precede the clinical diagnosis of active TB up to 2 years, paving the way for the development of immune based diagnostics to predict TB disease at an early stage. Show less
Fleischmann, R.; Heijde, D. van der; Koenig, A.S.; Pedersen, R.; Szumski, A.; Marshall, L.; Bananis, E. 2015
Crohn__s disease (CD) is characterized by chronic, patchy, transmural inflammation of the entire gastrointestinal tract, while ulcerative colitis (UC) is manifested by chronic, continuous,... Show moreCrohn__s disease (CD) is characterized by chronic, patchy, transmural inflammation of the entire gastrointestinal tract, while ulcerative colitis (UC) is manifested by chronic, continuous, superficial inflammation of the colon. Matrix metalloproteinases (MMPs) constitute a family of matrix degrading zinc and calcium-activated neutral endoproteinases, implicated in a wide range of biological processes. We found a marked upregulation of MMP-1, -2, -3 and -9 relative to their natural inhibitors, i.e., tissue inhibitors of metalloproteinases (TIMP) -1 and/or -2, in inflamed mucosa of IBD patients, paralleled by an increase in net MMP activity. Administration of TNF-alpha neutralizing antibody infliximab_ decreased MMP-1, -3 and -9 expression by cultured intestinal IBD explants and serum MMP-9 levels in CD patients, while MMP-2 levels remained almost the same. These observations suggest diverse regulator y pathways for the MMPs examined and a mechanistic pathway for infliximab_ in the treatment of CD. The T allele at TIMP-1 SNP locus +372 T/C, downregulating TIMP-1, appeared to enhance CD susceptibility and worsen prognosis of these patients. Ultimately, these studies might give rationale for the development of novel therapeutic drugs in IBD, based on the inhibition or activation of one or more members of the matrix metalloproteinases family. Show less
The host response to bacterial invasion requires first the recognition of the presence of pathogens. The presence of a pathogen is detected by binding of pathogen-preserved molecules called ... Show moreThe host response to bacterial invasion requires first the recognition of the presence of pathogens. The presence of a pathogen is detected by binding of pathogen-preserved molecules called 'pathogen-associated molecular patterns' or PAMPs on cell surface receptors known as 'pattern recognition receptors' or PRRs. Lipopolysaccharide (LPS; endotoxin), one of the major outer membrane components of the Gram-negative bacterial cell wall, is an important PAMP. In the last decade the mechanisms by which the host responds to the presence of microbial pathogens on its mucosal surfaces or in the tissues, have been elucidated, most up to their molecular level. With the sequencing of the genome and recognition of the genetic variation within the human population, it became clear this variation is responsible for the inter-individual differences in cytokine release after challenge with microbial products. Such genetically determined variations in cytokine release could be relevant to explain the variability in susceptibility too, and outcome from, sepsis. The thesis focuses on genes that encode for proteins involved in the pathogenesis of sepsis including those involved in the initial recognition of bacterial products such as Toll-like receptors, and cytokines known to mediate the host inflammatory response, such as tumor necrosis factor (TNF)-α, interleukin(IL)-6 and IL-10. Show less
