Gene expression-based molecular scoring of pancreas transplant rejection for a quantitative assessment of rejection severity and resistance to treatment.

Pancreas transplantation improves glycemic control and mortality in patients with diabetes but requires aggressive immunosuppression to control the alloimmune and autoimmune response. Recent developments in "omics" methods have provided gene transcript-based biomarkers for organ transplant rejection. The tissue Common Response Module (tCRM) score is developed to identify the severity of rejection in kidney, heart, liver, and lung transplants. Still, it has not yet been validated in pancreas transplants (PT). We evaluated the tCRM score's relevance in PT and additional markers of acute cellular rejection (ACR) for PT. An analysis of 51 pancreas biopsies with ACR identified 37 genes and 56 genes significantly upregulated in the case of grade 3 and grade 2 ACR, respectively (P < .05). Significant differences were seen with higher grades of rejection among several transcripts. Of the 22 genes differentially expressed in grade 3 ACR, 18 were also differentially expressed in grade 2 ACR. The rejection signal was attributable to activated leukocytes' infiltration. Significantly higher tCRM scores were found in grade 3 ACR (P = .007) and grade 2 ACR (P = .004), compared to normal samples. The tCRM score was able to distinguish treatment-resistant cases from those successfully treated for rejection.

Consent to organ offers from public health service "Increased Risk" donors decreases time to transplant and waitlist mortality.

BACKGROUND: The Public Health Service Increased Risk designation identified organ donors at increased risk of transmitting hepatitis B, hepatitis C, and human immunodeficiency virus. Despite clear data demonstrating a low absolute risk of disease transmission from these donors, patients are hesitant to consent to receiving organs from these donors. We hypothesize that patients who consent to receiving offers from these donors have decreased time to transplant and decreased waitlist mortality. METHODS: We performed a single-center retrospective review of all-comers waitlisted for liver transplant from 2013 to 2019. The three competing risk events (transplant, death, and removal from transplant list) were analyzed. 1603 patients were included, of which 1244 (77.6%) consented to offers from increased risk donors. RESULTS: Compared to those who did not consent, those who did had 2.3 times the rate of transplant (SHR 2.29, 95% CI 1.88-2.79, p < 0.0001), with a median time to transplant of 11 months versus 14 months (p < 0.0001), as well as a 44% decrease in the rate of death on the waitlist (SHR 0.56, 95% CI 0.42-0.74, p < 0.0001). All findings remained significant after controlling for the recipient age, race, gender, blood type, and MELD. Of those who did not consent, 63/359 (17.5%) received a transplant, all of which were from standard criteria donors, and of those who did consent, 615/1244 (49.4%) received a transplant, of which 183/615 (29.8%) were from increased risk donors. CONCLUSIONS: The findings of decreased rates of transplantation and increased risk of death on the waiting list by patients who were unwilling to accept risks of viral transmission of 1/300-1/1000 in the worst case scenarios suggests that this consent process may be harmful especially when involving "trigger" words such as HIV. The rigor of the consent process for the use of these organs was recently changed but a broader discussion about informed consent in similar situations is important.

Everolimus, an mTORC1/2 inhibitor, in ART-suppressed individuals who received solid organ transplantation: A prospective study.

Pharmacologic inhibition of the mammalian target of rapamycin (mTOR) in the setting of renal transplantation has previously been associated with lower human immunodeficiency virus 1 (HIV-1) DNA burden, and in vitro studies suggest that mTOR inhibition may lead to HIV transcriptional silencing. Because prospective clinical trials are lacking, we conducted an open-label, single-arm study to determine the impact of the broad mTOR inhibitor, everolimus, on residual HIV burden, transcriptional gene expression profiles, and immune responses in HIV-infected adult solid organ transplant (SOT) recipients on antiretroviral therapy. Whereas everolimus therapy did not have an overall effect on cell-associated HIV-1 DNA and RNA levels in the entire cohort, participants who maintained everolimus time-averaged trough levels >5 ng/mL during the first 2 months of therapy had significantly lower RNA levels up to 6 months after the cessation of study drug. Time-averaged everolimus trough levels significantly correlated with greater inhibition of mTOR gene pathway transcriptional activity. Everolimus treatment also led to decreased PD-1 expression on certain T cell subsets. These data support the rationale for further study of the effects of mTOR inhibition on HIV transcriptional silencing in non-SOT populations, either alone or in combination with other strategies. Trial Registration: ClinicalTrials.gov NCT02429869.

Long-term follow-up of beta cell replacement therapy in 10 HIV-infected patients with renal failure secondary to type 1 diabetes mellitus.

The approach to transplantation in human immunodeficiency virus (HIV)-positive patients has been conservative due to fear of exacerbating an immunocompromised condition. As a result, HIV-positive patients with diabetes were initially excluded from beta cell replacement therapy. Early reports of pancreas transplant in patients with HIV described high rates of early graft loss with limited follow-up. We report long-term follow-up of islet or pancreas transplantation in HIV-positive type 1 diabetic patients who received a kidney transplant concurrently or had previously undergone kidney transplantation. Although 4 patients developed polyoma viremia, highly active antiretroviral therapy and adequate infectious prophylaxis were successful in providing protection until CD4+ counts recovered. Coordination with HIV providers is critical to reduce the risk of rejection by minimizing drug-drug interactions. Also, protocols for prophylaxis of opportunistic infections and strategies for monitoring and treating BK viremia are important given the degree of immunosuppression required. This series demonstrates that type 1 diabetic patients with well-controlled HIV and renal failure can be appropriate candidates for beta cell replacement, with a low rate of infectious complications, early graft loss, and rejection, so excellent long-term graft survival is possible. Additionally, patients with HIV and cardiovascular contraindications can undergo islet infusion.

Update in preoperative risk assessment in vascular surgery patients.

Multiple clinical factors and now serum biomarkers may aid with risk stratification in vascular surgical patients. Herein, we review and update the clinical risk models, biomarker data, and currently used noninvasive cardiac stress tests. We also review the most recent American Heart Association guideline changes, and suggest a pathway for risk stratification.

A statewide colectomy experience: the role of full bowel preparation in preventing surgical site infection.

OBJECTIVE: To assess the utility of full bowel preparation with oral nonabsorbable antibiotics in preventing infectious complications after elective colectomy. BACKGROUND: Bowel preparation before elective colectomy remains controversial. We hypothesize that mechanical bowel preparation with nonabsorbable oral antibiotics is associated with a decreased rate of postoperative infectious complications when compared with no bowel preparation. METHODS: Patient and clinical data were obtained from the Michigan Surgical Quality Collaborative-Colectomy Best Practices Project. Propensity score analysis was used to match elective colectomy cases based on primary exposure variable-full bowel preparation (mechanical bowel preparation with nonabsorbable oral antibiotics) or no bowel preparation (neither mechanical bowel preparation given nor nonabsorbable oral antibiotic given). The primary outcomes for this study were occurrence of surgical site infection and Clostridium difficile colitis. RESULTS: In total, 2475 cases met the study criteria. Propensity analysis created 957 paired cases (n = 1914) differing only by the type of bowel preparation. Patients receiving full preparation were less likely to have any surgical site infection (5.0% vs 9.7%; P = 0.0001), organ space infection (1.6% vs 3.1%; P = 0.024), and superficial surgical site infection (3.0% vs 6.0%; P = 0.001). Patients receiving full preparation were also less likely to develop postoperative C difficile colitis (0.5% vs 1.8%, P = 0.01). CONCLUSIONS: In the state of Michigan, full bowel preparation is associated with decreased infectious complications after elective colectomy. Within this context, the Michigan Surgical Quality Collaborative recommends full bowel preparation before elective colectomy.

Perioperative changes in trunk musculature and postoperative outcomes.

BACKGROUND: Surgeons often face difficult decisions in selecting which patients can tolerate major surgical procedures. Although recent studies suggest the potential for trunk muscle size, as measured on preoperative imaging, to inform surgical risk, these measures are static and do not account for the effect of the surgery itself. We hypothesize that trunk muscle size will show dynamic changes over the perioperative period, and this change correlates with postoperative mortality risk. METHODS: A total of 425 patients who underwent inpatient general surgery were identified to have both a 90-d preoperative and a 90-d postoperative abdominal computed tomography scan. The change in trunk muscle size was calculated using analytic morphomic techniques. The primary outcome was 1-y survival. Covariate-adjusted outcomes were assessed using multivariable logistic regression. RESULTS: A total of 82.6% patients (n = 351) experienced a decrease in trunk muscle size in the time between their scans (average 62.1 d). When stratifying patients into tertiles of rate of change in trunk muscle size and adjusting for other covariates, patients in the tertile of the greatest rate loss had significantly increased risk of 1-y mortality than those in the tertile of the least rate loss (P = 0.002; odds ratio = 3.40 95% confidence interval, 1.55-7.47). The adjusted mortality rate for the tertile of the greatest rate loss was 24.0% compared with 13.3% for the tertile of the least decrease. CONCLUSIONS: Trunk muscle size changes rapidly in the perioperative period and correlates with mortality. Trunk muscle size may be a critical target for interventional programs focusing on perioperative optimization of the surgical patient.

An Enhanced Role of Innate Immunity in the Immune Response After Kidney Transplant in People Living With HIV: A Transcriptomic Analysis.

BACKGROUND: Although kidney transplantation (KT) has become the standard of care for people living with HIV (PLWH) suffering from renal failure, early experiences revealed unanticipated higher rejection rates than those observed in HIV- recipients. The cause of increased acute rejection (AR) in PLWH was assessed by performing a transcriptomic analysis of biopsy specimens, comparing HIV+ to HIV- recipients. METHODS: An analysis of 68 (34 HIV+, 34 HIV-) formalin-fixed paraffin-embedded (FFPE) renal biopsies matched for degree of inflammation was performed from KT recipients with acute T cell-mediated rejection (aTCMR), borderline for aTCMR (BL), and normal findings. Gene expression was measured using the NanoString platform on a custom gene panel to assess differential gene expression (DE) and pathway analysis (PA). RESULTS: DE analysis revealed multiple genes with significantly increased expression in the HIV+ cohort in aTCMR and BL relative to the HIV- cohort. PA of these genes showed enrichment of various inflammatory pathways, particularly innate immune pathways associated with Toll-like receptors. CONCLUSIONS: Upregulation of the innate immune pathways in the biopsies of PLWH with aTCMR and BL is suggestive of a unique immune response that may stem from immune dysregulation related to HIV infection. These findings suggest that these unique HIV-driven pathways may in part be contributory to the increased incidence of allograft rejection after renal transplantation in PLWH.

Long-term Outcomes Following Kidney and Liver Transplant in Recipients With HIV.

Importance: Kidney transplant (KT) and liver transplant (LT) in HIV-positive patients have become more widely adopted. Data looking at long-term outcomes of patient and graft survival are lacking. Objective: To compare the long-term outcomes of KT and LT in HIV-positive recipients with matched HIV-negative recipients. Design, Setting, and Participants: Retrospective, single-center, cohort, study using data from 2000 to 2019. Patients were observed until death, or graft failure requiring retransplant. All HIV-positive patients who underwent KT and/or LT between 2000 and 2019 were included. Propensity matching was performed to the corresponding HIV-negative cohort, which was obtained from the University of California, San Francisco's transplant recipient registry. The data were analyzed from 2020 to 2021. Exposures: HIV infection. Main Outcomes and Measures: Patient and graft survival for KT and patient survival for LT. Incidence of acute rejection and its association with KT graft survival. Results: For KT, 655 HIV-negative recipients (mean [SD] age, 52.3 [13.6] years; 450 [68.7%] were men) and 119 HIV-positive recipients (mean [SD] age, 51.7 [9.4] years; 86 [72.3%] were men) were included. Patient survival was 79.6% (95% CI, 73.6%-86.1%) and 53.6% (95% CI, 38.9%-74.0%) at 15 years posttransplant, respectively. Graft survival was 57.0% (95% CI, 47.8%-68.0%) and 75.0% (95% CI, 65.3%-86.2%) at 15 years posttransplant, respectively. Diagnosis of HIV was not associated with worse graft survival (hazard ratio, 1.09; 95% CI, 0.61-1.97; P = .77). For LT, 80 HIV-positive recipients (mean [SD] age, 52.6 [8.2] years; 53 [66.3%] were men) and 440 HIV-negative recipients (mean [SD] age, 54.6 [12.8] years; 291 [66.1%] were men) were included. Patient survival was 75.7% (95% CI, 71.8%-79.8%) for HIV-negative LT recipients and 70.0% (95% CI, 60.6%-80.8%) for HIV-positive LT recipients at 15 years posttransplant. Diagnosis of HIV was not a statistically significant predictor of patient survival (hazard ratio, 1.36; 95% CI, 0.83-2.24; P = .22). In KT, HIV-positive patients with at least 1 episode of acute rejection had a graft survival of 52.8% (95% CI, 38.4%-72.5%; P < .001) at 15 years posttransplant, compared with 91.8% in those without AR. Conclusions and Relevance: In this single-center cohort study, KT and LT in HIV-positive patients had comparable long-term outcomes with those in matched HIV-negative patients. The high incidence of acute rejection was associated with reduced graft survival. The findings support providing transplant to HIV-positive patients, which may be an appropriate use of transplant resources and provides equitable access for HIV-positive patients.

Single-cell RNA sequencing of Tocilizumab-treated peripheral blood mononuclear cells as an in vitro model of inflammation.

COVID-19 has posed a significant threat to global health. Early data has revealed that IL-6, a key regulatory cytokine, plays an important role in the cytokine storm of COVID-19. Multiple trials are therefore looking at the effects of Tocilizumab, an IL-6 receptor antibody that inhibits IL-6 activity, on treatment of COVID-19, with promising findings. As part of a clinical trial looking at the effects of Tocilizumab treatment on kidney transplant recipients with subclinical rejection, we performed single-cell RNA sequencing of comparing stimulated PBMCs before and after Tocilizumab treatment. We leveraged this data to create an in vitro cytokine storm model, to better understand the effects of Tocilizumab in the presence of inflammation. Tocilizumab-treated cells had reduced expression of inflammatory-mediated genes and biologic pathways, particularly amongst monocytes. These results support the hypothesis that Tocilizumab may hinder the cytokine storm of COVID-19, through a demonstration of biologic impact at the single-cell level.

Single-Cell RNA Sequencing of Tocilizumab-Treated Peripheral Blood Mononuclear Cells as an in vitro Model of Inflammation.

COVID-19 has posed a significant threat to global health. Early data has revealed that IL-6, a key regulatory cytokine, plays an important role in the cytokine storm of COVID-19. Multiple trials are therefore looking at the effects of Tocilizumab, an IL-6 receptor antibody that inhibits IL-6 activity, on treatment of COVID-19, with promising findings. As part of a clinical trial looking at the effects of Tocilizumab treatment on kidney transplant recipients with subclinical rejection, we performed single-cell RNA sequencing of comparing stimulated PBMCs before and after Tocilizumab treatment. We leveraged this data to create an in vitro cytokine storm model, to better understand the effects of Tocilizumab in the presence of inflammation. Tocilizumab-treated cells had reduced expression of inflammatory-mediated genes and biologic pathways, particularly amongst monocytes. These results support the hypothesis that Tocilizumab may hinder the cytokine storm of COVID-19, through a demonstration of biologic impact at the single-cell level.

Use of the Tissue Common Rejection Module Score in Kidney Transplant as an Objective Measure of Allograft Inflammation.

Long-term kidney transplant (KT) allograft outcomes have not improved as expected despite a better understanding of rejection and improved immunosuppression. Previous work had validated a computed rejection score, the tissue common rejection module (tCRM), measured by amplification-based assessment of 11 genes from formalin-fixed paraffin-embedded (FFPE) biopsy specimens, which allows for quantitative, unbiased assessment of immune injury. We applied tCRM in a prospective trial of 124 KT recipients, and contrasted assessment by tCRM and histology reads from 2 independent pathologists on protocol and cause biopsies post-transplant. Four 10-µm shaves from FFPE biopsy specimens were used for RNA extraction and amplification by qPCR of the 11 tCRM genes, from which the tCRM score was calculated. Biopsy diagnoses of either acute rejection (AR) or borderline rejection (BL) were considered to have inflammation present, while stable biopsies had no inflammation. Of the 77 biopsies that were read by both pathologists, a total of 40 mismatches in the diagnosis were present. The median tCRM scores for AR, BL, and stable diagnoses were 4.87, 1.85, and 1.27, respectively, with an overall significant difference among all histologic groups (Kruskal-Wallis, p < 0.0001). There were significant differences in tCRM scores between pathologists both finding inflammation vs. disagreement (p = 0.003), and both finding inflammation vs. both finding no inflammation (p < 0.001), along with overall significance between all scores (Kruskal-Wallis, p < 0.001). A logistic regression model predicting graft inflammation using various clinical predictor variables and tCRM revealed the tCRM score as the only significant predictor of graft inflammation (OR: 1.90, 95% CI: 1.40-2.68, p < 0.0001). Accurate, quantitative, and unbiased assessment of rejection of the clinical sample is critical. Given the discrepant diagnoses between pathologists on the same samples, individuals could utilize the tCRM score as a tiebreaker in unclear situations. We propose that the tCRM quantitative score can provide unbiased quantification of graft inflammation, and its rapid evaluation by PCR on the FFPE shave can become a critical adjunct to help drive clinical decision making and immunosuppression delivery.

Cell-Free DNA and CXCL10 Derived from Bronchoalveolar Lavage Predict Lung Transplant Survival.

Standard methods for detecting chronic lung allograft dysfunction (CLAD) and rejection have poor sensitivity and specificity and have conventionally required bronchoscopies and biopsies. Plasma cell-free DNA (cfDNA) has been shown to be increased in various types of allograft injury in transplant recipients and CXCL10 has been reported to be increased in the lung tissue of patients undergoing CLAD. This study used a novel cfDNA and CXCL10 assay to evaluate the noninvasive assessment of CLAD phenotype and prediction of survival from bronchoalveolar lavage (BAL) fluid. A total of 60 BAL samples (20 with bronchiolitis obliterans (BOS), 20 with restrictive allograft syndrome (RAS), and 20 with stable allografts (STA)) were collected from 60 unique lung transplant patients; cfDNA and CXCL10 were measured by the ELISA-based KIT assay. Median cfDNA was significantly higher in BOS patients (6739 genomic equivalents (GE)/mL) versus STA (2920 GE/mL) and RAS (4174 GE/mL) (p < 0.01 all comparisons). Likelihood ratio tests revealed a significant association of overall survival with cfDNA (p = 0.0083), CXCL10 (p = 0.0146), and the interaction of cfDNA and CXCL10 (p = 0.023) based on multivariate Cox proportional hazards regression. Dichotomizing patients based on the median cfDNA level controlled for the mean level of CXCL10 revealed an over two-fold longer median overall survival time in patients with low levels of cfDNA. The KIT assay could predict allograft survival with superior performance compared with traditional biomarkers. These data support the pursuit of larger prospective studies to evaluate the predictive performance of cfDNA and CXCL10 prior to lung allograft failure.

Outcomes associated with ablation compared to combined ablation and transilluminated powered phlebectomy in the treatment of venous varicosities.

BACKGROUND: Patients with painful varicose veins and venous insufficiency can be treated by eliminating axial reflux only or by eliminating axial reflux plus phlebectomy with transilluminated powered phlebectomy. This study was undertaken with the aim of determining and improving signs and symptoms of venous disease (measured by venous clinical severity score) and complications (by routine surveillance ultrasound and long-term post-operative follow up) for each treatment strategy. METHODS: We performed a retrospective evaluation of prospectively collected data from 979 limbs undergoing procedures for significant varicose veins and venous insufficiency from March 2008 until June 2014 performed at a single tertiary referral hospital. Patient demographics, Clinical Etiology Anatomy and Pathophysiology classification, venous clinical severity scores pre- and post-procedure, treatment chosen, and peri-operative complications were collected; descriptive statistics were calculated and unadjusted surgical outcomes for patients stratified by the procedure performed. Multivariable logistic regression was used to evaluate the relationship between procedure type and thrombotic complications after adjusting for patient characteristics, severity of disease, pre-operative anticoagulation, and post-operative compression. RESULT: Venous clinical severity scores improved more with radiofrequency ablation + transilluminated powered phlebectomy as compared to radiofrequency ablation alone (3.8 ± 3.4 vs. 3.2 ± 3.1, p = 0.018). Regarding deep venous thrombosis, there was no significant difference between radiofrequency ablation + transilluminated powered phlebectomy vs. radiofrequency ablation alone. There was no statistical difference in asymptomatic endovenous heat-induced thrombosis or infection, although there were slightly more hematomas and cases of asymptomatic superficial thrombophlebitis with combined therapy. On multivariable analysis, only procedure type predicted thrombotic complications. CONCLUSION: Ablation of axial reflux plus transilluminated powered phlebectomy produces improved outcomes as measured by venous clinical severity score, with slight increases in minor post-operative complications and should be strongly considered as initial therapy when patients present with significant symptomatic varicose veins and superficial venous insufficiency. Implementation of a standardized thromboprophylaxis protocol with individual risk assessment results in few significant thrombotic complications amongst high-risk patients, thus potentially obviating the need for routine post-operative duplex.