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Mucorales infections continue to cause significant morbidity and mortality in immunocompromised hosts despite the advent of new approaches for diagnosis and treatment of fungal infections. We aimed to evaluate risk factors and outcomes of Mucorales infection in solid organ transplant, hematopoietic cell transplant, and chimeric antigen receptor T-cell therapy recipients. This single-center retrospective study included solid organ transplant, hematopoietic cell transplant, and chimeric antigen receptor T-cell patients with cultures positive for Mucorales. Forty-three patients were included for analysis; 34 solid organ transplant (79%) and 9 hematopoietic stem cell transplant or chimeric antigen receptor T-cell (21%). Infection with Mucorales occurred a median of 184 days after transplant. At the time of diagnosis, 36 patients were on antifungal prophylaxis with the majority receiving posaconazole (53%). Thirty-three had clinically significant disease; 30 received definitive anti-Mucorales therapy and 3 empiric antifungal therapy. Isavuconazole was the most common azole used for treatment in monotherapy recipients. All-cause mortality was 64% and, of these deaths, 18 (75%) were directly related to Mucormycosis. The highest mortality was seen in disseminated and intra-abdominal disease (100%), followed by pulmonary disease (50%). There was no significant association with mortality and transplant type or number of immunosuppressive agents. Mucormycosis is an important cause of morbidity and mortality in immunocompromised patients. Breakthrough infection was not uncommon in this study. Data regarding the incidence of infection at approximately 6 months after transplantation can inform prophylaxis and treatment regimens. The spectrum of antifungal regimens used reflects the lack of consensus on ideal regimens for these organisms and a need for more studies. [ABSTRACT FROM AUTHOR]

These updated guidelines from the Infectious Diseases Community of Practice of the American Society of Transplantation review the diagnosis, prevention, and management of adenovirus infections after solid organ transplantation. Adenovirus is an important cause of infectious complications in both stem cell transplant and SOT patients, causing a range of clinical syndromes including pneumonitis, colitis, and disseminated disease. The current update of the guidelines highlights that adenovirus surveillance testing should not be performed in asymptomatic recipients. Serial quantitative PCR might play a role in the decision to initiate or assess response to therapy in a symptomatic patient. The initial and most important components of therapy remain supportive care and decrease in immunosuppression. The use of antiviral therapy is not supported by prospective randomized clinical trials. However, intravenous cidofovir is considered the standard practice for treatment of severe, progressive, or disseminated adenovirus disease in most transplant centers. Intravenous immunoglobulin may be beneficial, primarily in a select group of patients with hypogammaglobulinemia. Future approaches to treatment of adenovirus disease may include administration of adenovirus‐specific T‐cell therapy. [ABSTRACT FROM AUTHOR]

Background: Kidney transplant recipients (KTRs) are at risk for reactivation and complicated infection due to Coccidioides. Pre‐transplant serological screening should provide benefit for patients from endemic areas. We evaluated Coccidioides seroprevalence by area of residence in KTRs at a major transplant program in Los Angeles. Methods: We performed cross‐sectional analyses of adult KTRs who underwent transplantation at UCLA between 2007‐2016. Patients with Coccidioides serology by enzyme immunoassay (EIA) before or within 14 days from transplantation were included. Patients were classified as living in highly, established, suspected, or not endemic areas by their residential zip code. Results: Overall prevalence of Coccidioides IgG and IgM were 1.4% and 2.8%, respectively. Of patients with positive serology, 31.4% had isolated IgG and 66.3% isolated IgM. Patients from established and highly endemic areas had IgG seropositivity of 3.7% versus 1.3% for patients living in suspected endemic areas(P < .01). Rates of IgM seropositivity were 3.7% compared to 2.8% respectively (P = .28). No patients from non‐endemic areas had positive screening serology. Conclusions: Pre‐transplant serological screening for Coccidioides is recommended in kidney transplant candidates from endemic areas. We observed high seroprevalence among patients from highly and established endemic areas, for whom universal prophylaxis is recommended. For residents from less well‐established areas of endemicity, serological screening showed benefit in identifying patients at risk. In patients with isolated EIA IgM, performing repeat and confirmatory tests is recommended. Patients from non‐endemic areas had low risk of infection, however, a thorough social history is necessary to evaluate risk. [ABSTRACT FROM AUTHOR]

Transcriptional control of the hgl5 gene of Entamoeba histolytica is mediated through an unusual core promoter composed of TATA, GAAC and Initiator elements. In the hgl5 promoter the GAAC element (AATGAACT) determines the site and rate of transcription initiation. Here we tested the role of the GAAC element in transcription activation from upstream regulatory elements (UREs) in the hgl5 promoter. We also examined the function of the GAAC element in the ferredoxin (fdx) promoter and characterized the protein binding to the GAAC element. Electrophoretic mobility shift assays (EMSA) demonstrated that the GAAC region is necessary for higher-order nuclear protein complex assembly. The function of the GAAC element in transcription activation mediated by UREs revealed that mutation of the GAAC element did not affect transcription activation mediated by the hgl5 URE4 but abrogated activation by the hgl5 URE3. We compared the role of the GAAC elements in the hgl5 and fdx promoters. Competitive gel shift assays were consistent with the same nuclear protein binding to the GAAC elements in both genes. Mutation of the GAAC element in the fdx gene decreased reporter gene expression, however, in contrast to hgl5 gene, had no effect on the site of transcription initiation. These results support a role for the GAAC element in assembly of nuclear proteins at the core promoter and in transcription activation mediated by URE3. The differing effect on transcription initiation in the hgl5 and fdx genes upon mutation of the GAAC element suggests a context-dependence of the GAAC-binding protein in gene expression. [Copyright &y& Elsevier]

Aim A main cause of death in Advanced Heart Failure (AdHF) after Mechanical Circulatory Support Device (MCSD) is the Multiorgan Dysfunction Syndrome (MOD), mediated by an aberrant immune response. Since implantation of MCSD has immune modulating effects that may influence patient outcome, we hypothesized that T cell immunophenotyping would reflect assessment of patient risk before and after MCSD implant. Methods Peripheral blood was collected from 11 consented patients at days −1, 1, 3, 5 and 7 before and after MCSD surgery, and at 5 corresponding time points from 4 healthy controls. Multi-parameter flow cytometry was performed to measure CD4 and CD8 T cell maturation state as well as experienced and exhausted T cell subpopulations. Clinical risk was calculated using a modified Sequential Organ Failure Assessment (SOFA) score and the MELD-XI score. Results Multi-parameter immunophenotyping generated 34 CD4 and CD8 subpopulations. High scored MELD samples, obtained from higher risk patients, exhibited higher percentage of both effector and central memory CD8 cells (p = 0.0071 and p = 0.0001) and higher percentage of effector memory CD4 cells (p = 0.0074). There was a trend towards association with higher percentage of CD8+KLRG1+CD28 (p = 0.06) and lower %PD1+CD57+CD4+cells (p = 0.0785) compared with lower MELD scored patient samples. We further analyzed the data using stepwise and penalized regression methods. We reduced the number of predictors down to 3 T-cell subpopulations with immunophenotyping profile of chronically activated T cells: CD8+CD38+CD57+, CD4+CD38+CD57+ and CD4+CD38+KLRG1+. We used these subpopulations as the inputs to a linear mixed effect model to successfully predict the SOFA scores of patients’ samples. The overall model was found to be statistically significant (p = 0.006), and the regression coefficient for CD8+CD38+CD57 was statistically significant (p < 0.05). Conclussion Statistical modeling of T-cell subpopulation frequencies in peripheral blood of MOD patients can provide significant information predictive of their clinical phenotype, warranting further study for developing models to better predict patient outcomes. [ABSTRACT FROM AUTHOR]

Cytomegalovirus (CMV) infection and reactivation in solid organ transplant (SOT) recipients increases the risk of viremia, graft failure and death. Clinical studies of CMV serostatus indicate that donor positive recipient negative (D + /R - ) patients have greater viremia risk than D - /R - . The majority of patients are R + having intermediate serologic risk. To characterize the long-term impact of CMV infection and assess viremia risk, we sought to measure the effects of CMV on the recipient immune epigenome. Specifically, we profiled DNA methylation in 156 individuals before lung or kidney transplant. We found that the methylome of CMV positive SOT recipients is hyper-methylated at loci associated with neural development and Polycomb group (PcG) protein binding, and hypo-methylated at regions critical for the maturation of lymphocytes. In addition, we developed a machine learning-based model to predict the recipient CMV serostatus after correcting for cell type composition and ancestry. This CMV episcore measured at baseline in R + individual stratifies viremia risk accurately in the lung transplant cohort, and along with serostatus the CMV episcore could be a potential biomarker for identifying R + patients at high viremia risk.

Background: Kidney transplant (KT) candidates with HIV face higher mortality on the waitlist compared with candidates without HIV. Because the HIV Organ Policy Equity (HOPE) Act has expanded the donor pool to allow donors with HIV (D + ), it is crucial to understand whether this has impacted transplant rates for this population., Methods: Using a linkage between the HOPE in Action trial (NCT03500315) and Scientific Registry of Transplant Recipients, we identified 324 candidates listed for D + kidneys (HOPE) compared with 46 025 candidates not listed for D + kidneys (non-HOPE) at the same centers between April 26, 2018, and May 24, 2022. We characterized KT rate, KT type (D + , false-positive [FP; donor with false-positive HIV testing], D - [donor without HIV], living donor [LD]) and quantified the association between HOPE enrollment and KT rate using multivariable Cox regression with center-level clustering; HOPE was a time-varying exposure., Results: HOPE candidates were more likely male individuals (79% versus 62%), Black (73% versus 35%), and publicly insured (71% versus 52%; P  < 0.001). Within 4.5 y, 70% of HOPE candidates received a KT (41% D + , 34% D - , 20% FP, 4% LD) versus 43% of non-HOPE candidates (74% D - , 26% LD). Conversely, 22% of HOPE candidates versus 39% of non-HOPE candidates died or were removed from the waitlist. Median KT wait time was 10.3 mo for HOPE versus 60.8 mo for non-HOPE candidates ( P  < 0.001). After adjustment, HOPE candidates had a 3.30-fold higher KT rate (adjusted hazard ratio = 3.30, 95% confidence interval, 2.14-5.10; P  < 0.001)., Conclusions: Listing for D + kidneys within HOPE trials was associated with a higher KT rate and shorter wait time, supporting the expansion of this practice for candidates with HIV., Competing Interests: D.L.S. receives honoraria for AstraZeneca, CareDx, Houston Methodist, Northwell Health, Optum Health Education, Sanofi, and WebMd, as well as consulting fees from AstraZeneca, CareDx, Moderna Therapeutics, Novavax, Regeneron, and Springer Publishing. C.M.D. received honoraria from Gilead Sciences for serving on a grant review committee. V.S. received research grant support from Eli Lilly and Company and consulting fees from DiaSorin SpA. M.P. received grant support from Merck, Hologic, Moderna, Shire/Takeda, and Pfizer, as well as provided consultation to/serves on the advisory board for Rebiotix, Takeda, and Union Therapeutics. C.B.S. has received grants paid to her institution from GlaxoSmithKline, ViiV, Abbott, Merck, Gilead, Chimerix, Shire/Takeda, Schering-Plough, Ablynx, Janssen, Ansun Biopharma, and Karyopharm Therapeutics. G.H. is a recipient of research grants from Allovir, Karius, and AstraZeneca. G.H. serves on the scientific advisory boards of Karius and AstraZeneca and has received honoraria from MDOutlook and MAD-ID/ID Connect. J.H. is a recipient of grants paid to his institution from Pfizer, Janssen, and Scynexis. The other authors declare no conflicts of interest., (Copyright © 2023 Wolters Kluwer Health, Inc. All rights reserved.)

Introduction: Belatacept has shown potential for prevention of rejection after kidney transplantation, given its demonstration of reduced nephrotoxicity in combination with absence of significant incidence of rejection. However, concerns have been raised regarding increased risk of viral infection., Methods: We set out to explore the impact of the switch to belatacept on alloimmune and antiviral immunity through the study of patients switched from calcineurin inhibitor (CNI) to belatacept within 3 months of kidney transplantation compared with a matched cohort of control patients on a CNI-based regimen., Results: After the switch to belatacept, immune phenotyping demonstrated a decrease in naive and an increase in terminally differentiated effector memory (TMRA) T cells, with no significant difference compared with control patients. Donor-specific immune response, measured by intracellular cytokine staining (ICS), did not change significantly either by single or double cytokine secretion, but it was associated with the appearance of donor-specific antibody (DSA) in the control but not the belatacept cohort ( P  = 0.039 for naive and P  = 0.002 for TMRA subtypes). Increased incidence of de novo DSA development was observed in the control group ( P  = 0.035). Virus-specific immune response, as measured by ICS in response to cytomegalovirus (CMV) or Epstein-Barr virus (EBV), was similar in both groups and stable over time., Conclusion: We found that belatacept use was associated with an absence of alloreactivity without impact on immune phenotype, while preserving the antiviral immune response, for patients switched from a CNI-based regimen. In parallel, the antiviral immune response against CMV and EBV was preserved after the belatacept switch (clinicaltrials.gov: NCT01953120)., (© 2022 Published by Elsevier Inc. on behalf of the International Society of Nephrology.)

Cytomegalovirus (CMV) viremia continues to cause significant morbidity and mortality in kidney transplant patients with clinical complications including organ rejection and death. Whole blood gene expression dynamics in CMV viremic patients from onset of DNAemia through convalescence has not been well studied to date in humans. To evaluate how CMV infection impacts whole blood leukocyte gene expression over time, we evaluated a matched cohort of 62 kidney transplant recipients with and without CMV DNAemia using blood samples collected at multiple time points during the 12-month period after transplant. While transcriptomic differences were minimal at baseline between DNAemic and non-DNAemic patients, hundreds of genes were differentially expressed at the long-term timepoint, including genes enriching for pathways important for macrophages, interferon, and IL-8 signaling. Amongst patients with CMV DNAemia, the greatest amount of transcriptomic change occurred between baseline and 1-week post-DNAemia, with increase in pathways for interferon signaling and cytotoxic T cell function. Time-course gene set analysis of these differentially expressed genes revealed that most of the enriched pathways had a significant time-trend. While many pathways that were significantly down- or upregulated at 1 week returned to baseline-like levels, we noted that several pathways important in adaptive and innate cell function remained upregulated at the long-term timepoint after resolution of CMV DNAemia. Differential expression analysis and time-course gene set analysis revealed the dynamics of genes and pathways involved in the immune response to CMV DNAemia in kidney transplant patients. Understanding transcriptional changes caused by CMV DNAemia may identify the mechanism behind patient vulnerability to CMV reactivation and increased risk of rejection in transplant recipients and suggest protective strategies to counter the negative immunologic impact of CMV. These findings provide a framework to identify immune correlates for risk assessment and guiding need for extending antiviral prophylaxis., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2021 Ahn, Schaenman, Qian, Pickering, Groysberg, Rossetti, Llamas, Hoffmann, Gjertson, Deng, Bunnapradist, Reed and CMV Systems Immunobiology Group.)