Primary graft dysfunction (PGD) is the main cause of early morbidity and mortality after lung transplantation. Previous studies have yielded conflicting results for PGD risk factors.
We sought to ...identify donor, recipient, and perioperative risk factors for PGD.
We performed a 10-center prospective cohort study enrolled between March 2002 and December 2010 (the Lung Transplant Outcomes Group). The primary outcome was International Society for Heart and Lung Transplantation grade 3 PGD at 48 or 72 hours post-transplant. The association of potential risk factors with PGD was analyzed using multivariable conditional logistic regression.
A total of 1,255 patients from 10 centers were enrolled; 211 subjects (16.8%) developed grade 3 PGD. In multivariable models, independent risk factors for PGD were any history of donor smoking (odds ratio OR, 1.8; 95% confidence interval CI, 1.2-2.6; P = 0.002); FiO2 during allograft reperfusion (OR, 1.1 per 10% increase in FiO2; 95% CI, 1.0-1.2; P = 0.01); single lung transplant (OR, 2; 95% CI, 1.2-3.3; P = 0.008); use of cardiopulmonary bypass (OR, 3.4; 95% CI, 2.2-5.3; P < 0.001); overweight (OR, 1.8; 95% CI, 1.2-2.7; P = 0.01) and obese (OR, 2.3; 95% CI, 1.3-3.9; P = 0.004) recipient body mass index; preoperative sarcoidosis (OR, 2.5; 95% CI, 1.1-5.6; P = 0.03) or pulmonary arterial hypertension (OR, 3.5; 95% CI, 1.6-7.7; P = 0.002); and mean pulmonary artery pressure (OR, 1.3 per 10 mm Hg increase; 95% CI, 1.1-1.5; P < 0.001). PGD was significantly associated with 90-day (relative risk, 4.8; absolute risk increase, 18%; P < 0.001) and 1-year (relative risk, 3; absolute risk increase, 23%; P < 0.001) mortality.
We identified grade 3 PGD risk factors, several of which are potentially modifiable and should be prioritized for future research aimed at preventative strategies. Clinical trial registered with www.clinicaltrials.gov (NCT 00552357).
BACKGROUNDGermline mutations in telomerase and other telomere maintenance genes manifest in the premature aging short telomere syndromes. Myelodysplastic syndromes and acute myeloid leukemia ...(MDS/AML) account for 75% of associated malignancies, but how these cancers overcome the inherited telomere defect is unknown.METHODSWe used ultra-deep targeted sequencing to detect somatic reversion mutations in 17 candidate telomere lengthening genes among controls and patients with short telomere syndromes with and without MDS/AML, and we tested the functional significance of these mutations.RESULTSWhile no controls carried somatic mutations in telomere maintenance genes, 29% (16 of 56) of adults with germline telomere maintenance defects carried at least 1 (P < 0.001), and 13% (7 of 56) had 2 or more. In addition to TERT promoter mutations, which were present in 19%, another 13% of patients carried a mutation in POT1 or TERF2IP. POT1 mutations impaired telomere binding in vitro and some mutations were identical to ones seen in familial melanoma associated with longer telomere length. Exclusively in patients with germline defects in telomerase RNA (TR), we identified somatic mutations in nuclear RNA exosome genes RBM7, SKIV2L2, and DIS3, where loss-of-function upregulates mature TR levels. Somatic reversion events in 6 telomere-related genes were more prevalent in patients who were MDS/AML-free (P = 0.02, RR 4.4, 95% CI 1.2-16.7), and no patient with MDS/AML had more than 1 reversion mutation.CONCLUSIONOur data indicate that diverse adaptive somatic mutations arise in the short telomere syndromes. Their presence may alleviate the telomere crisis that promotes transformation to MDS/AML.FUNDINGThis work was supported by the NIH, the Commonwealth Foundation, the S&R Foundation Kuno Award, the Williams Foundation, the Vera and Joseph Dresner Foundation, the MacMillan Pathway to Independence Award, the American Society of Hematology Scholar Award, the Johns Hopkins Research Program for Medical Students, and the Turock Scholars Fund.
T cell polyfunctionality is a hallmark of protective immunity against pathogens and cancer, yet the molecular mechanism governing it remains mostly elusive. We found that canonical Wnt agonists ...inhibited human memory CD8+ T cell differentiation while simultaneously promoting the generation of highly polyfunctional cells. Downstream effects of Wnt activation persisted after removal of the drug, and T cells remained polyfunctional following subsequent cell division, indicating the effect is epigenetically regulated. Wnt activation induced a gene expression pattern that is enriched with stem cell-specific gene signatures and upregulation of protein arginine methyltransferase 1 (PRMT1), a known epigenetic regulator. PRMT1+CD8+ T cells are associated with enhanced polyfunctionality, especially the ability to produce IL-2. In contrast, inhibition of PRMT1 ameliorated the effects of Wnt on polyfunctionality. Chromatin immunoprecipitation revealed that H4R3me2a, a permissive transcription marker mediated by PRMT1, increased at the IL-2 promoter loci following Wnt activation. In vivo, Wnt-treated T cells exhibited superior polyfunctionality and persistence. When applied to cytomegalovirus (CMV) donor-seropositive, recipient-seronegative patients (D+/R-) lung transplant patient samples, Wnt activation enhanced CMV-specific T cell polyfunctionality, which is important in controlling CMV diseases. These findings reveal a molecular mechanism governing T cell polyfunctionality and identify PRMT1 as a potential target for T cell immunotherapy.
Background.
The impacts of COVID-19 on lung allograft function, rejection, secondary infection, and clinical outcomes in lung transplant recipients (LTRs) remain unknown.
Methods.
A 1:2 matched ...case–control study was performed to evaluate rehospitalization, lung allograft function, and secondary infections up to 90 d after COVID-19 diagnosis (or index dates for controls).
Results.
Twenty-four LTRs with COVID-19 (cases) and 48 controls were identified. Cases and controls had similar baseline characteristics and lung allograft function. LTRs with COVID-19 had higher incidence of secondary bacterial infection (29.2% versus 6.3%,
P
= 0.008), readmission (29.2% versus 10.4%,
P
= 0.04), and for-cause bronchoscopy (33.3% versus 12.5%,
P
= 0.04) compared with controls. At d 90, mortality in cases versus controls was 8.3% versus 2.1% (
P
= 0.21), incidence of invasive fungal infections in cases versus controls was 20.8% versus 8.3% (
P
= 0.13) and forced expiratory volume in 1 s (FEV
1
) decline ≥10% from baseline occurred in 19% of cases versus 12.2% of controls (
P
= 0.46). No acute cellular rejection, acute antibody-mediated rejection, or new donor-specific anti-HLA antibodies were observed among cases or controls within 90 d post index date.
Conclusions.
We found LTRs with COVID-19 were at risk to develop secondary infections and rehospitalization post COVID-19, compared with controls. While we did not observe post viral acute cellular rejection or antibody-mediated rejection, further studies are needed to understand if LTRs with COVID-19 who did not recover baseline lung function within 90 d have developed chronic lung allograft dysfunction stage progression.
Although several studies have evaluated risk factors for death after lung transplantation (LTx), few studies have focused on the highest-risk recipients. We undertook this study to evaluate the ...effect of high lung allocation scores (LAS), ventilator support, and extracorporeal membrane oxygenation (ECMO) support on outcomes after LTx.
We retrospectively reviewed all LTx recipients in the United Network for Organ Sharing database. Primary stratification was by recipient acuity at the time of LTx. The 3 strata consisted of (1) recipients in the highest LAS quartile (LAS ≥ 48.4), (2) those requiring ventilator support, and (3) those requiring ECMO support. The primary outcome was 1-year mortality. Sub-group analysis focused on temporal trends.
From May 2005 to June 2011, 9,267 adults underwent LTx. Before LTx, 1,874 (20.2%) were in the highest LAS quartile, 526 (5.7%) required ventilator support, and 122 (1.3%) required ECMO support. Unadjusted analysis showed decreased 1-year survival associated with ventilator (67.7%) and ECMO support (57.6%) compared with the highest LAS quartile (81.0%; p < 0.001 for each comparison). These differences persisted on adjusted analysis for ventilator support (hazard ratio, 1.99, p < 0.001) and ECMO support (hazard ratio, 3.03; p < 0.001). Increasing annual center volume was associated with decreased mortality. In patients bridged to LTx with ECMO support, 1-year survival improved over time (coefficient, 8.03% per year; p = 0.06).
High-acuity LTx recipients, particularly those bridged with ventilator or ECMO support, have increased short-term mortality after LTx. However, since the introduction of the LAS, high-risk patients have demonstrated improving outcomes, particularly at high-volume centers.
Lung transplantation is the only intervention that prolongs survival in idiopathic pulmonary fibrosis (IPF). Telomerase mutations are the most common identifiable genetic cause of IPF, and at times, ...the telomere defect manifests in extrapulmonary disease such as bone marrow failure. The relevance of this genetic diagnosis for lung transplant management has not been examined. We gathered an international series of telomerase mutation carriers who underwent lung transplant in the U.S.A., Australia and Sweden. The median age at transplant was 52 years. Seven recipients are alive with a median follow-up of 1.9 years (range 6 months to 9 years); one died at 10 months. The most common complications were haematological, with recipients requiring platelet transfusion support (88%) and adjustment of immunosuppressives (100%). Four recipients (50%) required dialysis for tubular injury and calcineurin inhibitor toxicity. These complications occurred at significantly higher rates relative to historic series (p<0.0001). Our observations support the feasibility of lung transplantation in telomerase mutation carriers; however, severe post-transplant complications reflecting the syndromic nature of their disease appear to occur at higher rates. While these findings need to be expanded to other cohorts, caution should be exercised when approaching the transplant evaluation and management of this subset of pulmonary fibrosis patients.
Human metapneumovirus (HMPVi) and parainfluenza virus (PIVi) infections are common community-acquired infections in lung transplant recipients (LTRs), but data are extremely limited.
A retrospective ...study including all LTRs at the Johns Hopkins Hospital during July 2010-June 2019 with positive HMPV and PIV polymerase chain reaction respiratory specimens was performed.
Thirty-one HMPV- and 53 PIV-infected LTRs were identified. LTRs with HMPVi and PIVi had similar baseline characteristics, infection parameters, treatment allocation, and allograft function outcomes. Among entire cohort, 31.6% had chronic allograft dysfunction (CLAD) stage progression within 1 y postinfections (29.2% versus 35.5% for PIVi versus HMPVi, respectively, P = 0.56). In forced expiratory volume in 1 s percent (FEV1%) trajectory analysis showed steadily decline of FEV1 across time among CLAD stage progressors from both viruses. FEV1% decline ≥10% at 90 d had adjusted hazard ratio for CLAD stage progression of 18.4 (4.98-67.76) and 4.6 (1.36-15.34) for PIVi and HMPVi, respectively. PIVi caused higher donor-specific antigen development (11.8% versus 3.2%, P = 0.18) and 1-y mortality (9.4% versus 0%, P = 0.11), compared with HMPVi, even though the results were not statistically significant. Ribavirin did not show protective effect, and mycophenolate discontinuation during infection did not increase risk of CLAD stage progression.
One-third of HMPV- and PIV-infected LTRs developed CLAD stage progression within 1 y. The lack of early lung function recovery may predict long-term CLAD progression.
While several studies have observed that solid organ transplant recipients experience diminished antibody responses to SARS-CoV-2 mRNA vaccination, data specific to heart and lung transplant (HT/LT) ...recipients remains sparse.
US adult HT and LT recipients completed their vaccine series between January 7 and April 10, 2021. Reactogencity and SARS-CoV-2 anti-spike antibody were assessed after a priming dose (D1) and booster dose (D2). Modified Poisson regression with robust variance estimator was used to evaluate associations between participant characteristics and antibody development.
Of 134 heart recipients, there were 38% non-responders (D1-/D2-), 48% booster responders (D1-/D2+), and 14% priming dose responders (D1+/D2+). Of 103 lung recipients, 64% were non-responders, 27% were booster responders, and 9% were priming dose responders. Lung recipients were less likely to develop antibodies (p < .001). Priming dose antibody response was associated with younger recipient age (p = .04), transplant-to-vaccination time ≥6 years (p < .01), and lack of anti-metabolite maintenance immunosuppression (p < .001). Pain at injection site was the most commonly reported reaction (85% after D1, 76% after D2). Serious reactions were rare, the most common being fatigue (2% after D1 and 3% after D2). No serious adverse events were reported.
HT and LT recipients experienced diminished antibody response following vaccination; reactogenicity was comparable to that of the general population. LT recipients may exhibit a more impaired antibody response than HT recipients. While current recommendations are to vaccinate eligible candidates and recipients, further studies characterizing the cell-mediated immune response and clinical efficacy of these vaccines in this population are needed.