Life underneath the VCA umbrella: Perspectives from the US Uterus Transplant Consortium

The parallel emergence of uterus transplantation (UTx) and other transplantation innovations including face and hand transplantation led to the categorization of the uterus as a vascular composite allograft (VCA). With >60 transplants and >20 births worldwide, UTx is transitioning rapidly from a research endeavor to an effective treatment option for women with uterine factor infertility. While it originally made sense to group the innovations under one umbrella, it is time to revisit the designation of UTx as a VCA. We describe how UTx needs unique policy, procedural codes, insurance contracts, and educational initiatives. We contend that separating UTx from VCAs may become necessary in the future to avoid hindering the growth and regulation of this field.     

Long-term kidney transplant graft survival—Making progress when most needed

Current short-term kidney post–transplant survival rates are excellent, but longer-term outcomes have historically been unchanged. This study used data from the national Scientific Registry of Transplant Recipients (SRTR) and evaluated 1-year and 5-year graft survival and half-lives for kidney transplant recipients in the US. All adult (≥18 years) solitary kidney transplants (n = 331,216) from 1995 to 2017 were included in the analysis. Mean age was 49.4 years (SD +/-13.7), 60% male, and 25% Black. The overall (deceased and living donor) adjusted hazard of graft failure steadily decreased from 0.89 (95%CI: 0.88, 0.91) in era 2000–2004 to 0.46 (95%CI: 0.45, 0.47) for era 2014–2017 (1995–1999 as reference). Improvements in adjusted hazards of graft failure were more favorable for Blacks, diabetics and older recipients. Median survival for deceased donor transplants increased from 8.2 years in era 1995–1999 to an estimated 11.7 years in the most recent era. Living kidney donor transplant median survival increased from 12.1 years in 1995–1999 to an estimated 19.2 years for transplants in 2014–2017. In conclusion, these data show continuous improvement in long-term outcomes with more notable improvement among higher-risk subgroups, suggesting a narrowing in the gap for those disadvantaged after transplantation.     

Complement inhibition for prevention of antibody-mediated rejection in immunologically high-risk heart allograft recipients

Allosensitization represents a major barrier to heart transplantation (HTx). We assessed the efficacy and safety of complement inhibition at transplant in highly sensitized heart transplant recipients. We performed a single-center, single-arm, open-label trial (NCT02013037). Patients with panel reactive antibodies (PRA) ≥70% and pre–formed donor-specific antibodies (DSA) were eligible. In addition to standard of care, patients received nine infusions of eculizumab during the first 2 months posttransplant. The primary composite endpoint was antibody-mediated rejection (AMR) ≥pAMR2 and/or left ventricular dysfunction during the first year. Secondary endpoints included hemodynamic compromise, allograft rejection, and patient survival. Twenty patients were included. Median cPRA and mean fluorescence intensity of immunodominant DSA were 95% (90%–97%) and 6250 (5000–10 000), respectively. Retrospective B cell and T cell flow crossmatches were positive in 14 and 11 patients, respectively. The primary endpoint occurred in four patients (20%). Survival at 1 year was 90% with no deaths resulting from AMR. In a prespecified analysis comparing treated patients to matched control patients, we observed a dramatic reduction in the risk of biopsy-proven AMR in patients treated with eculizumab (HR = 0.36, 95% CI = 0.14–0.95, p = .032). Our findings support the prophylactic use of complement inhibition for heart transplantation at high immunological risk. ClinincalTrials.gov, NCT02013037.     

Association of antiviral prophylaxis and rituximab use with posttransplant lymphoproliferative disorders (PTLDs): A nationwide cohort study

Posttransplant lymphoproliferative disorder (PTLD) is a serious complication of solid organ transplantation (SOT). Most PTLD cases are associated with Epstein–Barr virus (EBV) infection. The role of antiviral prophylaxis or rituximab therapy for prevention of PTLD in SOT recipients is controversial. In a nationwide cohort, we assessed the incidence, presentation, and outcome of histologically proven PTLD. We included 4765 patients with a follow-up duration of 23 807 person-years (py). Fifty-seven PTLD cases were identified; 39 (68%) were EBV positive (EBV+ PTLD). Incidence rates for EBV+ PTLD at 1, 2, and 3 years posttransplant were 3.51, 2.24, and 1.75/1000 py and 0.44, 0.25, and 0.29/1000 py for EBV− PTLD. We did not find an effect of antiviral prophylaxis on early and late EBV+ PTLD occurrence (early EBV+ PTLD: SHR 0.535 [95% CI 0.199–1.436], p = .264; late EBV+ PTLD: SHR 2.213, [95% CI 0.751–6.521], p = .150). However, none of the patients (0/191) who received a rituximab-containing induction treatment experienced PTLD, but 57 of 4574 patients without rituximab induction developed PTLD. In an adjusted restricted mean survival time model, PTLD-free survival was significantly longer (0.104 years [95% CI 0.077–0.131]) in patients receiving rituximab as induction treatment. This study provides novel data on the association of rituximab induction and reduced risk for PTLD.     

Optimal donation of kidney transplants after controlled circulatory death

Controlled donation after circulatory death (cDCD) is used for “extended criteria” donors with poorer kidney transplant outcomes. The French cDCD program started in 2015 and is characterized by normothermic regional perfusion, hypothermic machine perfusion, and short cold ischemia time. We compared the outcomes of kidney transplantation from cDCD and brain-dead (DBD) donors, matching cDCD and DBD kidney transplants by propensity scoring for donor and recipient characteristics. The matching process retained 442 of 499 cDCD and 809 of 6185 DBD transplantations. The DGF rate was 20% in cDCD recipients compared with 28% in DBD recipients (adjusted relative risk [aRR], 1.43; 95% confidence interval [CI] 1.12–1.82). When DBD transplants were ranked by cold ischemia time and machine perfusion use and compared with cDCD transplants, the aRR of DGF was higher for DBD transplants without machine perfusion, regardless of the cold ischemia time (aRR with cold ischemia time <18 h, 1.57; 95% CI 1.20–2.03, vs aRR with cold ischemia time ≥18 h, 1.79; 95% CI 1.31–2.44). The 1-year graft survival rate was similar in both groups. Early outcome was better for kidney transplants from cDCD than from matched DBD transplants with this French protocol.     

Increased incidence and unusual presentations of CMV disease in kidney transplant recipients after conversion to belatacept

Belatacept may increase cytomegalovirus (CMV) disease risk after conversion from CNI-based therapy. We analyzed CMV disease characteristics after belatacept conversion. Propensity score matching was used to compare CMV disease incidence in belatacept- and CNI-treated kidney transplant recipients (KTRs). CMV disease characteristics and risk factors under belatacept were analyzed. In total, 223 KTRs (median age [IQR] 59.2 years [45.4–68.5]) were converted to belatacept (median of 11.5 months [2.5–37.0] post-transplantation); 40/223 (17.9%) developed CMV disease. Independent risk factors included increased age (p = .0164), D+/R− CMV serostatus (p = .0220), and low eGFR at conversion (p = .0355). Among 181 belatacept-treated patients matched to 181 controls, 32/181 (17.7%) experienced CMV disease (vs. 5/181 controls [2.8%]). CMV disease cumulative incidences were 6.33 and 0.91/100 person-years (p-y) in belatacept and control groups, respectively. CMV disease risk was particularly high in elderly patients (converted >70 years) and those with eGFR <30 ml/min; cumulative incidences were 18.4 and 5.2/100 p-y, respectively. CMV diseases under belatacept were atypical, with late-onset disease (24/40 patients [60%]), high CMV seropositivity (27/40, 67%), increased severe and tissue-invasive disease rates (gastrointestinal involvement in 32/40 [80%]) and life-threatening diseases (4/40 [10%]). These findings should stimulate further research to secure the use of belatacept as a valuable rescue therapy in KTRs.     

Effect of delayed graft function on longer-term outcomes after kidney transplantation from donation after circulatory death donors in the United Kingdom: A national cohort study

Kidneys from donation after circulatory death (DCD) donors are utilized variably worldwide, in part due to high rates of delayed graft function (DGF) and putative associations with adverse longer-term outcomes. We aimed to determine whether the presence of DGF and its duration were associated with poor longer-term outcomes after kidney transplantation from DCD donors. Using the UK transplant registry, we identified 4714 kidney-only transplants from controlled DCD donors to adult recipients between 2006 and 2016; 2832 recipients (60·1%) had immediate graft function and 1882 (39·9%) had DGF. Of the 1847 recipients with DGF duration recorded, 926 (50·1%) had DGF < 7 days, 576 (31·2%) had DGF 7–14 days, and 345 (18·7%) had DGF >14 days. After risk adjustment, the presence of DGF was not associated with inferior long-term graft or patient survivals. However, DGF duration of >14 days was associated with an increased risk of death-censored graft failure (hazard ratio 1·7, p = ·001) and recipient death (hazard ratio 1·8, p < ·001) compared to grafts with immediate function. This study suggests that shorter periods of DGF have no adverse influence on graft or patient survival after DCD donor kidney transplantation and that DGF >14 days is a novel early biomarker for significantly worse longer-term outcomes.     

Safety and immunogenicity of adjuvanted recombinant subunit herpes zoster vaccine in lung transplant recipients

Lung transplant recipients are at high risk for herpes zoster and preventive measures are a significant unmet need. We investigated the safety and immunogenicity of two doses of a recombinant zoster vaccine (RZV) in lung transplant recipients (≥50 years). We enrolled 50 patients of which 49 received at least one vaccine dose. Anti-glycoprotein E (gE) antibody levels (n = 43) increased significantly compared to baseline (median optical density [OD] 1.96; interquartile range [IQR]: 1.17–2.89) after the first (median OD 3.41, IQR 2.54–3.81, p < .0001) and second vaccine dose (median OD 3.63, IQR 3.39–3.86, p < .0001). gE-specific polyfunctional CD4+ T cell frequencies (n = 38) also increased from baseline (median 85 per 10⁶ CD4+ T cells; IQR: 46–180) to the first (median 128 per 10⁶ CD4+ T cells; IQR: 82–353; p = .023) and after the second dose (median 361 per 10⁶ CD4+ T cells; IQR: 146–848; p < .0001). Tenderness (83.0%; 95%CI: 69.2–92.4%) and redness (31.9%; 95%CI: 19.1–47.1%) at injection site were common. One rejection episode within 3 weeks of vaccination was observed. This is the first study demonstrating that RZV was safe and elicited significant humoral and cell-mediated immunity in lung transplant recipients. RZV is a new option for the prevention of shingles in this population.     

Distinct immunopathological mechanisms of EBV-positive and EBV-negative posttransplant lymphoproliferative disorders

EBV-positive and EBV-negative posttransplant lymphoproliferative disorders (PTLDs) arise in different immunovirological contexts and might have distinct pathophysiologies. To examine this hypothesis, we conducted a multicentric prospective study with 56 EBV-positive and 39 EBV-negative PTLD patients of the K-VIROGREF cohort, recruited at PTLD diagnosis and before treatment (2013–2019), and compared them to PTLD-free Transplant Controls (TC, n = 21). We measured absolute lymphocyte counts (n = 108), analyzed NK- and T cell phenotypes (n = 49 and 94), and performed EBV-specific functional assays (n = 16 and 42) by multiparameter flow cytometry and ELISpot-IFNγ assays (n = 50). EBV-negative PTLD patients, NK cells overexpressed Tim-3; the 2-year progression-free survival (PFS) was poorer in patients with a CD4 lymphopenia (CD4⁺<300 cells/mm³, p <  .001). EBV-positive PTLD patients presented a profound NK-cell lymphopenia (median = 60 cells/mm³) and a high proportion of NK cells expressing PD-1 (vs. TC, p = .029) and apoptosis markers (vs. TC, p < .001). EBV-specific T cells of EBV-positive PTLD patients circulated in low proportions, showed immune exhaustion (p = .013 vs. TC) and poorly recognized the N-terminal portion of EBNA-3A viral protein. Altogether, this broad comparison of EBV-positive and EBV-negative PTLDs highlight distinct patterns of immunopathological mechanisms between these two diseases and provide new clues for immunotherapeutic strategies and PTLD prognosis.