Outcome of lung transplantation for adults with interstitial lung disease associated with genetic disorders of the surfactant system.

Background: Interstitial lung disease associated with genetic disorders of the surfactant system is a rare entity in adults that can lead to lung transplantation. Our objective was to describe the outcome of these patients after lung transplantation. Methods: We conducted a retrospective, multicentre study, on adults who underwent lung transplantation for such disease in the French lung transplant centres network, from 1997 to 2018. Results: 20 patients carrying mutations in SFTPA1 (n=5), SFTPA2 (n=7) or SFTPC (n=8) were included. Median interquartile range (IQR) age at diagnosis was 45 (40-48) years, and median (IQR) age at lung transplantation was 51 (45-54) years. Median overall survival after transplantation was 8.6 years. Two patients had a pre-transplant history of lung cancer, and two developed post-transplant lung cancer. Female gender and a body mass index <25 kg·m-2 were significantly associated with a better prognosis, whereas transplantation in high emergency was associated with a worst prognosis. Conclusions: Lung transplantation in adults with interstitial lung disease associated with genetic disorders of surfactant system may be a valid therapeutic option. Our data suggest that these patients may have a good prognosis. Immunosuppressive protocol was not changed for these patients, and close lung cancer screening is needed before and after transplantation.

Hypomorphic pathogenic variant in SFTPB leads to adult pulmonary fibrosis.

Biallelic pathogenic variants in the surfactant protein (SP)-B gene (SFTPB) have been associated with fatal forms of interstitial lung diseases (ILD) in newborns and exceptional survival in young children. We herein report the cases of two related adults with pulmonary fibrosis due to a new homozygous SFTPB pathogenic variant, c.582G>A p.(Gln194=). In vitro transcript studies showed that this SFTPB synonymous pathogenic variant induces aberrant splicing leading to three abnormal transcripts with the preservation of the expression of a small proportion of normal SFTPB transcripts. Immunostainings on lung biopsies of the proband showed an almost complete loss of SP-B expression. This hypomorphic splice variant has thus probably allowed the patients' survival to adulthood while inducing an epithelial cell dysfunction leading to ILD. Altogether, this report shows that SFTPB pathogenic variants should be considered in atypical presentations and/or early-onset forms of ILD particularly when a family history is identified.

Changes in HCMV immune cell frequency and phenotype are associated with chronic lung allograft dysfunction.

Background: Human cytomegalovirus (HCMV) infection is common and often severe in lung transplant recipients (LTRs), and it is a risk factor associated with chronic lung allograft dysfunction (CLAD). The complex interplay between HCMV and allograft rejection is still unclear. Currently, no treatment is available to reverse CLAD after diagnosis, and the identification of reliable biomarkers that can predict the early development of CLAD is needed. This study investigated the HCMV immunity in LTRs who will develop CLAD. Methods: This study quantified and phenotyped conventional (HLA-A2pp65) and HLA-E-restricted (HLA-EUL40) anti-HCMV CD8+ T (CD8 T) cell responses induced by infection in LTRs developing CLAD or maintaining a stable allograft. The homeostasis of immune subsets (B, CD4T, CD8 T, NK, and γδT cells) post-primary infection associated with CLAD was also investigated. Results: At M18 post-transplantation, HLA-EUL40 CD8 T responses were less frequently found in HCMV+ LTRs (21.7%) developing CLAD (CLAD) than in LTRs (55%) keeping a functional graft (STABLE). In contrast, HLA-A2pp65 CD8 T was equally detected in 45% of STABLE and 47.8% of CLAD LTRs. The frequency of HLA-EUL40 and HLA-A2pp65 CD8 T among blood CD8 T cells shows lower median values in CLAD LTRs. Immunophenotype reveals an altered expression profile for HLA-EUL40 CD8 T in CLAD patients with a decreased expression for CD56 and the acquisition of PD-1. In STABLE LTRs, HCMV primary infection causes a decrease in B cells and inflation of CD8 T, CD57+/NKG2C+ NK, and δ2-γδT cells. In CLAD LTRs, the regulation of B, total CD8 T, and δ2+γδT cells is maintained, but total NK, CD57+/NKG2C+ NK, and δ2-γδT subsets are markedly reduced, while CD57 is overexpressed across T lymphocytes. Conclusions: CLAD is associated with significant changes in anti-HCMV immune cell responses. Our findings propose that the presence of dysfunctional HCMV-specific HLA-E-restricted CD8 T cells together with post-infection changes in the immune cell distribution affecting NK and γδT cells defines an early immune signature for CLAD in HCMV+ LTRs. Such a signature may be of interest for the monitoring of LTRs and may allow an early stratification of LTRs at risk of CLAD.

Determinants of survival after lung transplantation in telomerase-related gene mutation carriers: A retrospective cohort.

Carriers of germline telomerase-related gene (TRG) mutations can show poor prognosis, with an increase in common hematological complications after lung transplantation (LT) for pulmonary fibrosis. The aim of this study was to describe the outcomes after LT in recipients carrying a germline TRG mutation and to identify the predictors of survival. In a multicenter cohort of LT patients, we retrospectively reviewed those carrying pathogenic TRG variations (n = 38; TERT, n = 23, TERC, n = 9, RTEL1, n = 6) between 2009 and 2018. The median age at LT was 54 years (interquartile range [IQR] 46-59); 68% were male and 71% had idiopathic pulmonary fibrosis. During the diagnosis of pulmonary fibrosis, 28 (74%) had a hematological disease, including eight with myelodysplasia. After a median follow-up of 26 months (IQR 15-46), 38 patients received LT. The overall post-LT median survival was 3.75 years (IQR 1.8-NA). The risk of death after LT was increased for patients with myelodysplasia (HR 4.1 [95% CI 1.5-11.5]) or short telomere (HR 2.2 [1.0-5.0]) before LT. After LT, all patients had anemia, 66% had thrombocytopenia, and 39% had neutropenia. Chronic lung allograft dysfunction frequency was 29% at 4 years. The present findings support the use of LT in TRG mutation carriers without myelodysplasia. Hematological evaluation should be systematically performed before LT.

Lung transplantation for sarcoidosis: outcome and prognostic factors.

STUDY QUESTION: In patients with sarcoidosis, past and ongoing immunosuppressive regimens, recurrent disease in the transplant and extrapulmonary involvement may affect outcomes of lung transplantation. We asked whether sarcoidosis lung phenotypes can be differentiated and, if so, how they relate to outcomes in patients with pulmonary sarcoidosis treated by lung transplantation. PATIENTS AND METHODS: We retrospectively reviewed data from 112 patients who met international diagnostic criteria for sarcoidosis and underwent lung or heart-lung transplantation between 2006 and 2019 at 16 European centres. RESULTS: Patient survival was the main outcome measure. At transplantation, median (interaquartile range (IQR)) age was 52 (46-59) years; 71 (64%) were male. Lung phenotypes were individualised as follows: 1) extended fibrosis only; 2) airflow obstruction; 3) severe pulmonary hypertension (sPH) and airflow obstruction; 4) sPH, airflow obstruction and fibrosis; 5) sPH and fibrosis; 6) airflow obstruction and fibrosis; 7) sPH; and 8) none of these criteria, in 17%, 16%, 17%, 14%, 11%, 9%, 5% and 11% of patients, respectively. Post-transplant survival rates after 1, 3, and 5 years were 86%, 76% and 69%, respectively. During follow-up (median (IQR) 46 (16-89) months), 31% of patients developed chronic lung allograft dysfunction. Age and extended lung fibrosis were associated with increased mortality. Pulmonary fibrosis predominating peripherally was associated with short-term complications. ANSWER TO THE STUDY QUESTION: Post-transplant survival in patients with pulmonary sarcoidosis was similar to that in patients with other indications for lung transplantation. The main factors associated with worse survival were older age and extensive pre-operative lung fibrosis.

COVID-19 in Lung Transplant Recipients.

BACKGROUND: A concern about the susceptibility of immunocompromised patients to the worldwide pandemic of coronavirus disease 2019 (COVID-19) has been raised. We aimed at describing COVID-19 infections in the French cohort of lung transplant (LT) patients. METHODS: Multicenter nationwide cohort study of all LT recipients with COVID-19 diagnosed from March 1 to May 19, 2020. Recipient main characteristics and their management were retrieved. Hospitalization characteristics, occurrence of complications and survival were analyzed. RESULTS: Thirty-five LT patients with a COVID-19 infection were included. Median age was 50.4 (40.6-62.9) years, 16 (45.7%) were female, and 80% were double-LT recipients. Infection was community-acquired in 25 (71.4%). Thirty-one (88.6%) required hospitalization, including 13 (41.9%) in the intensive care unit. The main symptoms of COVID-19 were fever, cough, and diarrhea, present in 71.4%, 54.3%, and 31.4% of cases, respectively. Extension of pneumonia on chest CT was moderate to severe in 51.4% of cases. Among the 13 critically ill patients, 7 (53.9%) received invasive mechanical ventilation. Thrombotic events occurred in 4 patients. Overall survival rate was 85.7% after a median follow-up of 50 days (41.0-56.5). Four of 5 nonsurvivors had had bronchial complications or intensification of immunosuppression in the previous weeks. On univariate analysis, overweight was significantly associated with risk of death (odds ratio, 16.0; 95% confidence interval, 1.5-170.6; P = 0.02). CONCLUSIONS: For the 35 LT recipients with COVID-19, the presentation was severe, requiring hospitalization in most cases, with a survival rate of 85.7%.

Functional assessment and phenotypic heterogeneity of SFTPA1 and SFTPA2 mutations in interstitial lung diseases and lung cancer.

INTRODUCTION: Interstitial lung diseases (ILDs) can be caused by mutations in the SFTPA1 and SFTPA2 genes, which encode the surfactant protein (SP) complex SP-A. Only 11 SFTPA1 or SFTPA2 mutations have so far been reported worldwide, of which five have been functionally assessed. In the framework of ILD molecular diagnosis, we identified 14 independent patients with pathogenic SFTPA1 or SFTPA2 mutations. The present study aimed to functionally assess the 11 different mutations identified and to accurately describe the disease phenotype of the patients and their affected relatives. METHODS: The consequences of the 11 SFTPA1 or SFTPA2 mutations were analysed both in vitro, by studying the production and secretion of the corresponding mutated proteins and ex vivo, by analysing SP-A expression in lung tissue samples. The associated disease phenotypes were documented. RESULTS: For the 11 identified mutations, protein production was preserved but secretion was abolished. The expression pattern of lung SP-A available in six patients was altered and the family history reported ILD and/or lung adenocarcinoma in 13 out of 14 families (93%). Among the 28 SFTPA1 or SFTPA2 mutation carriers, the mean age at ILD onset was 45 years (range 0.6-65 years) and 48% underwent lung transplantation (mean age 51 years). Seven carriers were asymptomatic. DISCUSSION: This study, which expands the molecular and clinical spectrum of SP-A disorders, shows that pathogenic SFTPA1 or SFTPA2 mutations share similar consequences for SP-A secretion in cell models and in lung tissue immunostaining, whereas they are associated with a highly variable phenotypic expression of disease, ranging from severe forms requiring lung transplantation to incomplete penetrance.