Immunomodulation And Androgen Roles In IPF And Clinical Safety Assessment Of Pirfenidone

Section 1:The Role of Genetic Factors in the Pathogenesis of Idiopathic Pulmonary FibrosisBackground and Objectives:Genetic factors play a role in the risk of idiopathic pulmonary fibrosis(IPF).MUC5B rs35705950 non-risk alleles and immunologic aberrations were associated with the IPF’s progression.However,rare genetic variants have not been systematically investigated in Chinese IPF patients.In this study,we aimed to improve understanding of the genetic architecture of IPF in Chinese population and to assess whether rare protein-coding variants in immunity pathway genes are enriched in the IPF patients with non-risk alleles at rs35705950.Methods:A case-control exome-wide study including 110 IPF patients and 60 matched healthy controls was conducted.rs35705950 was genotyped by Sanger sequencing.To identify genes enriched in IPF,gene-based association analyses were performed.Identified genes were included for further pathway analyses using gene ontology(GO)and Kyoto Encyclopedia of Genes and Genomes(KEGG).Associations between rs35705950 and genes enriched in immunity pathway were also tested.Results:226 genes that were enriched with deleterious variants were identified in the IPF patients.Out of them,36 genes were significantly enriched in GO and KEGG pathways in IPF.Pathway analyses implicated that these genes were involved in immune response and cell adhesion.Rare protein-altering variants in genes related to immunity pathway did not significantly differ between patients with a MUC5B risk allele and individuals without risk allele.Conclusion:We drafted a comprehensive mutational landscape of rare protein-coding variants in the Chinese IPF and identified genes related to immune response and cell adhesion.These results partially explain changes in gene expression involved in immunity/inflammatory pathways in IPF patients.Section 2:Expression and Potential Role of B7H3 in Idiopathic Pulmonary FibrosisBackground and Objectives:The clinical significance and role of B7H3 and its cleavage product soluble B7H3(sB7H3)in progression of IPF is unknown.This study aimed to investigate the plasma levels of sB7H3 and circulating B7H3+cells in IPF patients and assess for any correlation with lung function and/or immune cells as well as potential role in pathogenesis.Methods:Plasma sB7H3 and B7H3+cells were analyzed in IPF patient blood samples by ELISA and flow cytometry,respectively.To analyze its function,the effect of sB7H3 on naive or bleomycin-treated mice.Results:Plasma levels of sB7H3 and circulating B7H3+cell were increased in IPF patients with both being negatively correlated with lung function,and interestingly,especially after nintedanib therapy.The percentage of B7H3+cell was positively correlated with sB7H3 or Tregs.In mice,sB7H3 injection induced an influx of myeloid-derived suppressor cells(MDSCs)and Ccl2 expression in lung tissue,accompanied by enhanced overall inflammation.Additionally,sB7H3 caused accumulation of MDSCs in bone marrow with expression of inflammatory cytokines.Notably in vitro assays revealed chemotaxis of MDSCs to sB7H3,which was dependent on TLT-2.Conclusion:The correlation of sB7H3 with deterioration of lung function might be due to its ability to enhance inflammation and recruitment of MDSCs into the lung and their expansion in the bone marrow via binding to its putative receptor,TLT-2.Section 3:The Potential Role of Sex hormones in the Pathogenesis of Idiopathic Pulmonary FibrosisBackground and Objectives:IPF is an aging-related lung disorder featuring progressive lung scarring.Short telomeres are frequently identified in IPF patients,but coding mutations in telomerase can only explain a minority of those patients.Sex hormones regulate telomerase activity in vitro and levels of sex hormones are related to leukocyte telomere length(LTL).The objective of the study was to explore whether sex hormones associated with LTL,whether they interact with genetic variants in telomerase and whether polymorphisms in the exon of androgen metabolism genes were associated with testosterone in male IPF patients.Methods:A case-control study was performed on 101 male IPF cases and 51 age-matched healthy controls.Early-morning plasma sex hormones were quantified,and whole-exome sequencing was used to identify rare protein-altering variants of telomerase and single nucleotide polymorphisms(SNPs)in the exon of androgen metabolism genes.LTL was analyzed by PCR and expressed as T/S ratio.Results:LTL,testosterone and dihydrotestosterone decreased significantly in the IPF group.After adjustments for age and variant status in telomerase-related genes,only testosterone was positively associated with LTL(P=0.001).No significant interaction(P=0.661)was observed between rare protein-altering variants of telomerase and testosterone.No coding SNPs in androgen metabolism genes were significantly associated with testosterone concentrations.Conclusion:Plasma testosterone associates with LTL independently of age and rare protein-altering variants of telomerase.No genetic variations of androgen-related pathway genes are associated with androgen concentrations.Further studies are warranted to examine whether hormonal interventions might retard telomere loss in male IPF patients.Section 4:Real-world Experiences:Efficacy and Tolerability of Pirfenidone in Clinical PracticeBackground and Objectives:The safety of pirfenidone on pulmonary fibrosis patients with other kinds of interstitial lung diseases(ILDs)in addition to IPF is unknown.Furthermore,its effectiveness-related factors on IPF patients are not quite explored.In this study,we aimed to evaluate the effectiveness of pirfenidone in patients with IPF and its tolerability in all patients with lung fibrosis.Methods:We conducted a retrospective study of patients with pulmonary fibrosis treated with pirfenidone.The effectiveness of pirfenidone was tested on 110 IPF subjects receiving treatment for≥3 months by high-resolution computed tomography(HRCT).Response-linked factors and progression-free survival(PFS)were also analyzed.The data about safety outcomes and drug dose adjustments were collected from all included subjects.Results:A total of 176 subjects were included:117 were IPF,19 connective tissue disease associated interstitial lung disease(CTD-ILD),and 40 unclassifiable ILD.Out of the 110 IPF subjects,89 subjects were assessed as stable and 21 as progressive,out of which 10 died of acute exacerbation and 11 progressed.The effectiveness was significantly related to their baseline body mass index(BMI).IPF subjects with BMI>25kg/m2 or diffusion capacity of carbon monoxide(DLCO)>30%had higher PFS rate.The most common adverse events were skin-related and gastrointestinal-related.Drug discontinuation owing to adverse events occurred similarly in these three groups.Conclusion:Pirfenidone was well tolerated in most of the lung fibrosis patients besides IPF,with a similar pattern of adverse events.Nearly 80%of IPF subjects were assessed as stable.More benefits were seen in IPF patients with higher BMI or mild-to-moderate disease.