Adult provider role in transition of care for young adult pediatric recipients of liver transplant: An expert position statement.

Health care transition (HCT) is the process of changing from a pediatric to an adult model of care. Young adult pediatric recipients of liver transplant transferring from pediatric to adult health care services are highly vulnerable and subject to poor long-term outcomes. Barriers to successful transition are multifaceted. A comprehensive HCT program should be initiated early in pediatrics and continued throughout young adulthood, even after transfer of care has been completed. It is critical that pediatric and adult liver transplant providers establish a partnership to optimize care for these patients. Adult providers must recognize the importance of HCT and the need to continue the transition process following transfer. While this continued focus on HCT is essential, current literature has primarily offered guidance for pediatric providers. This position paper outlines a framework with a sample set of tools for the implementation of a standardized, multidisciplinary approach to HCT for adult transplant providers utilizing "The Six Core Elements of HCT." To implement more effective strategies and work to improve long-term outcomes for young adult patients undergoing liver transplant, HCT must be mandated as a routine part of posttransplant care. Increased advocacy efforts with the additional backing and support of governing organizations are required to help facilitate these practices.

Pediatric liver transplant recipients are not just young adults: The importance of a structured health care transition program in adult transplant centers.

Health care transition (HCT) is a vulnerable period that continues into adulthood, even after the transfer of care. Given the growing population of pediatric liver transplant recipients reaching young adulthood, the need for a standardized and multidisciplinary approach to transition that spans from pediatric to adult care is becoming more imperative. In this article, we review the unique challenges and barriers to successful HCT that adolescent and young adults (AYAs) who have undergone liver transplant face, highlight the gap in transition care in the adult setting, and present the Six Core Elements of Health Care TransitionTM as a framework that can be used by adult providers to incorporate AYAs systematically and collaboratively into adult practice. Multidisciplinary HCT programs should be the standard of care for all AYAs with liver transplant, and while implementation is a necessary first step, ongoing efforts to increase awareness, funding, and research on HCTs into adulthood are needed.

The Root-Lesion Nematode, Pratylenchus penetrans, Affects Early Growth and Physiology of Grafted M.9, G.41, and G.935 Apple Rootstocks Similarly Under Field Microplot Conditions.

The root-lesion nematode, Pratylenchus penetrans, is a ubiquitous parasite of roots of temperate fruit trees. It affects early growth of trees replanted into former orchard sites where populations have built up and may contribute to decline complexes of older trees. Most British Columbia, Canada, apple acreage is planted with M.9 rootstock, but growers are increasingly considering Geneva-series rootstocks such as G.41 and G.935. Among these rootstocks, responses to P. penetrans, specifically, are poorly known. To compare the resistance and tolerance to P. penetrans of G.41, G.935, and M.9 rootstocks ('Ambrosia' scion), a field microplot experiment was established in spring of 2020 at the Summerland Research and Development Centre. The experimental design was a two by three factorial combination of: P. penetrans inoculation (+/-) and rootstock (G.41, G.935, and M.9), with 20 replicate microplots of each of the six treatment combinations arranged in a randomized complete block design. The P. penetrans inoculum was 5,400 nematodes per microplot (54 P. penetrans liter-1 soil), which is below commonly accepted damage thresholds. Though P. penetrans population densities were lower for the G.41 rootstock by the end of the 2021 growing season, the effects of P. penetrans were similar among rootstocks. In the establishment year (2020), P. penetrans caused significant reductions in aboveground growth. In 2021, shoot growth and root weight were reduced by P. penetrans. The nematode also reduced rates of leaf gas exchange and stem water potential. These data suggest that while G.41 and G.935 may have other horticultural benefits over M.9, they are equally susceptible to P. penetrans at the early stages of tree growth.

Post-Transplant Management and Complications of Autoimmune Hepatitis, Primary Biliary Cholangitis, and Primary Sclerosing Cholangitis including Disease Recurrence.

Autoimmune liver diseases have unique post-transplant considerations. These recipients are at increased risk of rejection, and recurrent disease may also develop, which can progress to graft loss and increase mortality. Monitoring for and managing these complications is therefore important, though data on associated risk factors and immunosuppression strategies has in most cases been mixed. There are also other disease-specific complications that require management and may impact these decisions, including inflammatory bowel disease in PSC. Further work to better understand the optimal management strategies for these patients post-transplant is needed.

Psychosocial impact of recurrent urogenital infections: a review.

Recurrent urogenital infections such as bacterial vaginosis, vulvovaginal candidiasis, and urinary tract infections have a high prevalence and pronounced psychosocial impact. However, no review has compared the psychosocial impacts across infection types. This narrative review discusses the impact of common recurrent urogenital infections on psychosocial aspects, including quality of life, stress, mental health, sexual health, work productivity, race and ethnicity, and satisfaction of medical care. Validated questionnaires show that women with recurrent vulvovaginal candidiasis and urinary tract infections have decreased scores on all aspects of quality of life. Those with recurrent vulvovaginal candidiasis and urinary tract infections show lower mental health scores compared to the general population, with increased risk of anxiety and depression. Recurrent urogenital infections affect sexual relationships and intimacy, including avoidance due to symptoms or as a method of prevention. Recurrent infections also increase medical cost and negatively affect work productivity, leading to a combined estimated cost of over US$13 billion per year. There are clear effects of racial inequality involving minority populations that affect diagnosis, treatment, prevalence, and reporting of recurrent urogenital infections. Satisfactory medical treatment improves quality of life and mental health in those suffering from these conditions. Research evaluating psychosocial aspects of recurrent urogenital infections is variable and is not comparable across vulvovaginal conditions. Even so, psychosocial factors are important in understanding contribution and consequence of urogenital infections. Education, awareness, normalization, community support, and access to care can help to alleviate the negative implications of recurrent urogenital infections.

A narrative review discussing the psychosocial impact of common recurrent urogenital infections and highlights areas where further research is needed to improve clinical care.

Real-world Experiences in the Transplantation of Hepatitis C-NAAT-positive Organs.

Background: Hepatitis C virus (HCV) nucleic acid amplification test (NAAT)-positive donors have increased the organ pool. Direct-acting antivirals (DAAs) have led to high rates of treatment success and sustained virologic response (SVR) in recipients with donor-derived HCV infection without significant adverse effects, although variability remains in the timing and duration of antivirals. Methods: This retrospective study analyzed all adult HCV-NAAT-negative transplant recipients who received an organ from HCV-NAAT-positive donors from November 24, 2018, to March 31, 2022, at Duke University Medical Center with protocolized delay of DAA initiation until after hospital discharge, with at least 180-d follow-up on all patients. Transplant and HCV-related outcomes were analyzed. Results: Two hundred eleven transplants (111 kidneys, 41 livers, 34 hearts, and 25 lungs) were performed from HCV-NAAT-positive donors to HCV-NAAT-negative recipients. Ninety percent of recipients became viremic within 7 d posttransplant. Ninety-nine percent of recipients were initiated on pangenotypic DAAs in the outpatient setting a median of 52 d posttransplant, most commonly with 12-wk courses of sofosbuvir-velpatasvir (lungs) and glecaprevir-pibrentasvir (heart, kidney, and liver). Ninety-seven percent of recipients had SVR after a first-line DAA; all ultimately achieved SVR at 12 wk after subsequent treatment courses. The median peak HCV RNA for all organ systems was 2 436 512 IU/mL; the median time from antiviral to undetectable RNA was 48 d, although differences were noted between organ groups. No patient deaths or graft losses were directly attributable to HCV infection. Conclusions: One hundred percent of transplant recipients of HCV-NAAT-positive organs ultimately developed SVR without significant adverse effects when HCV antivirals were initiated in the outpatient setting after transplant hospitalization, suggesting that this real-world treatment pathway is a viable option.

2022 White Paper on Recent Issues in Bioanalysis: Enzyme Assay Validation, BAV for Primary End Points, Vaccine Functional Assays, Cytometry in Tissue, LBA in Rare Matrices, Complex NAb Assays, Spectral Cytometry, Endogenous Analytes, Extracellular Vesicles Part 2 - Recommendations on Biomarkers/CDx, Flow Cytometry, Ligand-Binding Assays Development & Validation; Emerging Technologies; Critical Reagents Deep Characterization.

The 16th Workshop on Recent Issues in Bioanalysis (16th WRIB) took place in Atlanta, GA, USA on September 26-30, 2022. Over 1000 professionals representing pharma/biotech companies, CROs, and multiple regulatory agencies convened to actively discuss the most current topics of interest in bioanalysis. The 16th WRIB included 3 Main Workshops and 7 Specialized Workshops that together spanned 1 week in order to allow exhaustive and thorough coverage of all major issues in bioanalysis, biomarkers, immunogenicity, gene therapy, cell therapy and vaccines. Moreover, in-depth workshops on ICH M10 BMV final guideline (focused on this guideline training, interpretation, adoption and transition); mass spectrometry innovation (focused on novel technologies, novel modalities, and novel challenges); and flow cytometry bioanalysis (rising of the 3rd most common/important technology in bioanalytical labs) were the special features of the 16th edition. As in previous years, WRIB continued to gather a wide diversity of international, industry opinion leaders and regulatory authority experts working on both small and large molecules as well as gene, cell therapies and vaccines to facilitate sharing and discussions focused on improving quality, increasing regulatory compliance, and achieving scientific excellence on bioanalytical issues. This 2022 White Paper encompasses recommendations emerging from the extensive discussions held during the workshop and is aimed to provide the bioanalytical community with key information and practical solutions on topics and issues addressed, in an effort to enable advances in scientific excellence, improved quality and better regulatory compliance. Due to its length, the 2022 edition of this comprehensive White Paper has been divided into three parts for editorial reasons. This publication (Part 2) covers the recommendations on LBA, Biomarkers/CDx and Cytometry. Part 1 (Mass Spectrometry and ICH M10) and Part 3 (Gene Therapy, Cell therapy, Vaccines and Biotherapeutics Immunogenicity) are published in volume 15 of Bioanalysis, issues 16 and 14 (2023), respectively.

Current approach to health care transition and integration into adult care for pediatric liver transplant recipients: A call for partnership.

Despite the increased risk of non-adherence, allograft rejection, and mortality following transfer from pediatric to adult care in liver transplantation (LT), there is no standardized approach to health care transition (HCT). Two electronic national surveys were developed and distributed to members of the Society for Pediatric Liver Transplantation and all adult LT programs in the United States to examine current HCT practices. Responses were received from 40 pediatric and 79 adult centers. Pediatric centers were more likely to focus on HCT noting the presence of a transition/transfer policy (60.2% vs. 39.2%), transition clinic (51.6% vs. 16.5%), and the routine use of transition readiness assessment tools (54.8% vs. 10.2%). Perceived barriers to HCT were similar among pediatric and adult respondents and included patient willingness to transfer and participate in care, failure to show for appointments, and lack of sufficient time and staffing. These results highlight the need for an increased awareness of HCT at both pediatric and adult LT centers. The path to improvement requires a partnership between pediatric and adult providers. Recognizing the importance of a comprehensive HCT program initiated in pediatrics and continued throughout young adulthood with ongoing support by the adult team is essential.

Mass cytometry for the multiplexed quantification and characterization of target expression on circulating cells in whole blood.

Characterization of target abundance on cells has broad translational applications. Among the approaches for assessing membrane target expression is quantification of the number of target-specific antibody (Ab) bound per cell (ABC). ABC determination on relevant cell subsets in complex and limited biological samples necessitates multidimensional immunophenotyping, for which the high-order multiparameter capabilities of mass cytometry provide considerable advantages. In the present study, we describe the implementation of CyTOF® for the concomitant quantification of membrane markers on diverse types of immune cells in human whole blood. Specifically, our protocol relies on establishing Bmax of Ab saturable binding on cells, then converted into ABC according to a metal's transmission efficiency and number of metal atoms per Ab. Using this method, we calculated ABC values for CD4 and CD8 within the expected range for circulating T cells and in concordance with the ABC obtained in the same samples by flow cytometry. Furthermore, we successfully conducted multiplex measurements of the ABC for CD28, CD16, CD32a, and CD64, on >15 immune cell subsets in human whole blood samples. We developed a high-dimensional data analysis workflow enabling semi-automated Bmax calculation in all examined cell subsets to facilitate ABC reporting across populations. In addition, we investigated impacts of the type of metal isotope and acquisition batch effect on the ABC evaluation with CyTOF®. In summary, our findings demonstrate mass cytometry is a valuable tool for concurrent quantitative analysis of multiple targets in specific and rare cell types, thus increasing the numbers of biomeasures obtained from a single sample.

Health Care Transition for Adolescents and Young Adults With Pediatric-Onset Liver Disease and Transplantation: A Position Paper by the North American Society of Pediatric Gastroenterology, Hepatology, and Nutrition.

Advances in medical therapies and liver transplantation have resulted in a greater number of pediatric patients reaching young adulthood. However, there is an increased risk for medical complications and morbidity surrounding transfer from pediatric to adult hepatology and transplant services. Health care transition (HCT) is the process of moving from a child/family-centered model of care to an adult or patient-centered model of health care. Successful HCT requires a partnership between pediatric and adult providers across all disciplines resulting in a transition process that does not end at the time of transfer but continues throughout early adulthood. Joint consensus guidelines in collaboration with the American Society of Transplantation are presented to facilitate the adoption of a structured, multidisciplinary approach to transition planning utilizing The Six Core Elements of Health Care Transition TM for use by both pediatric and adult specialists. This paper provides guidance and seeks support for the implementation of an HCT program which spans across both pediatric and adult hepatology and transplant centers.

Itching to find a diagnosis.

Content available: Audio Recording.

Evaluation of EDB Fibronectin in Plasma, Patient-Derived Xenograft Formalin-Fixed Paraffin-Embedded and Fresh Frozen Tumor Tissues Using Immunoaffinity LC-MS/MS.

The fibronectin (FN) isoform including the extradomain B (EDB) segment (EDB + FN) is a promising tumor target and is highly expressed in some tumor types, such as breast, head, and neck cancer. To date, mostly immunohistochemistry (IHC) and Western blot have been used for the analysis of EDB + FN. However, complete quantitative measurements of EDB + FN expression in a tumor and circulation are important for the development of anti-EDB therapeutics. To this end, a method using protein enrichment followed by online antipeptide antibody enrichment coupled with a nanoflow LC-MS/MS was developed to quantify EDB + FN in human and cynomolgus plasma, patient-derived xenograft (PDX) tumors, and PDX formalin-fixed paraffin-embedded (FFPE) samples. Mouse plasma EDB + FN was analyzed using a protein immunoaffinity method followed by nanoflow LC-MS/MS. EDB + FN concentrations were 63.1 pmol/g in PDX breast cancer tumor and 49.6 pmol/g in PDX head and neck tumor. Mean plasma concentration was 1.1 nM (pmol/mL, 47.4 ng/mL) in normal healthy humans and 0.35 nM (15.1 ng/mL) in naive cynomolgus. The assay sensitivity was 0.018 nM based on calibration with recombinant human EDB + FN (rhEDB + FN).

2021 White Paper on Recent Issues in Bioanalysis: ISR for Biomarkers, Liquid Biopsies, Spectral Cytometry, Inhalation/Oral & Multispecific Biotherapeutics, Accuracy/LLOQ for Flow Cytometry (Part 2 - Recommendations on Biomarkers/CDx Assays Development & Validation, Cytometry Validation & Innovation, Biotherapeutics PK LBA Regulated Bioanalysis, Critical Reagents & Positive Controls Generation).

The 15th edition of the Workshop on Recent Issues in Bioanalysis (15th WRIB) was held on 27 September to 1 October 2021. Even with a last-minute move from in-person to virtual, an overwhelmingly high number of nearly 900 professionals representing pharma and biotech companies, contract research organizations (CROs), and multiple regulatory agencies still eagerly convened to actively discuss the most current topics of interest in bioanalysis. The 15th WRIB included three Main Workshops and seven Specialized Workshops that together spanned 1 week in order to allow exhaustive and thorough coverage of all major issues in bioanalysis, biomarkers, immunogenicity, gene therapy, cell therapy and vaccines. Moreover, in-depth workshops on biomarker assay development and validation (BAV) (focused on clarifying the confusion created by the increased use of the term "context of use" [COU]); mass spectrometry of proteins (therapeutic, biomarker and transgene); state-of-the-art cytometry innovation and validation; and critical reagent and positive control generation were the special features of the 15th edition. This 2021 White Paper encompasses recommendations emerging from the extensive discussions held during the workshop, and is aimed to provide the bioanalytical community with key information and practical solutions on topics and issues addressed, in an effort to enable advances in scientific excellence, improved quality and better regulatory compliance. Due to its length, the 2021 edition of this comprehensive White Paper has been divided into three parts for editorial reasons. This publication (Part 2) covers the recommendations on ISR for Biomarkers, Liquid Biopsies, Spectral Cytometry, Inhalation/Oral & Multispecific Biotherapeutics, Accuracy/LLOQ for Flow Cytometry. Part 1A (Endogenous Compounds, Small Molecules, Complex Methods, Regulated Mass Spec of Large Molecules, Small Molecule, PoC), Part 1B (Regulatory Agencies' Inputs on Bioanalysis, Biomarkers, Immunogenicity, Gene & Cell Therapy and Vaccine) and Part 3 (TAb/NAb, Viral Vector CDx, Shedding Assays; CRISPR/Cas9 & CAR-T Immunogenicity; PCR & Vaccine Assay Performance; ADA Assay Comparability & Cut Point Appropriateness) are published in volume 14 of Bioanalysis, issues 9 and 11 (2022), respectively.

More Than Meets the Eye?

Content available: Author Audio Recording.

Preclinical Evaluation of 89Zr-Df-IAB22M2C PET as an Imaging Biomarker for the Development of the GUCY2C-CD3 Bispecific PF-07062119 as a T Cell Engaging Therapy.

PURPOSE: A sensitive and specific imaging biomarker to monitor immune activation and quantify pharmacodynamic responses would be useful for development of immunomodulating anti-cancer agents. PF-07062119 is a T cell engaging bispecific antibody that binds to CD3 and guanylyl cyclase C, a protein that is over-expressed by colorectal cancers. Here, we used 89Zr-Df-IAB22M2C (89Zr-Df-Crefmirlimab), a human CD8-specific minibody to monitor CD8+ T cell infiltration into tumors by positron emission tomography. We investigated the ability of 89Zr-Df-IAB22M2C to track anti-tumor activity induced by PF-07062119 in a human CRC adoptive transfer mouse model (with injected activated/expanded human T cells), as well as the correlation of tumor radiotracer uptake with CD8+ immunohistochemical staining. PROCEDURES: NOD SCID gamma mice bearing human CRC LS1034 tumors were treated with four different doses of PF-07062119, or a non-targeted CD3 BsAb control, and imaged with 89Zr-Df-IAB22M2C PET at days 4 and 9. Following PET/CT imaging, mice were euthanized and dissected for ex vivo distribution analysis of 89Zr-Df-IAB22M2C in tissues on days 4 and 9, with additional data collected on day 6 (supplementary). Data were analyzed and reported as standard uptake value and %ID/g for in vivo imaging and ex vivo tissue distribution. In addition, tumor tissues were evaluated by immunohistochemistry for CD8+ T cells. RESULTS: The results demonstrated substantial mean uptake of 89Zr-Df-IAB22M2C (%ID/g) in PF-07062119-treated tumors, with significant increases in comparison to non-targeted BsAb-treated controls, as well as PF-07062119 dose-dependent responses over time of treatment. A moderate correlation was observed between tumor tissue radioactivity uptake and CD8+ cell density, demonstrating the value of the imaging agent for non-invasive assessment of intra-tumoral CD8+ T cells and the mechanism of action for PF-07062119. CONCLUSION: Immune-imaging technologies for quantitative cellular measures would be a valuable biomarker in immunotherapeutic clinical development. We demonstrated a qualification of 89Zr-IAB22M2C PET to evaluate PD responses (mice) to a novel immunotherapeutic.

Discovery and optimization of a novel anti-GUCY2c x CD3 bispecific antibody for the treatment of solid tumors.

We report here the discovery and optimization of a novel T cell retargeting anti-GUCY2C x anti-CD3ε bispecific antibody for the treatment of solid tumors. Using a combination of hybridoma, phage display and rational design protein engineering, we have developed a fully humanized and manufacturable CD3 bispecific antibody that demonstrates favorable pharmacokinetic properties and potent in vivo efficacy. Anti-GUCY2C and anti-CD3ε antibodies derived from mouse hybridomas were first humanized into well-behaved human variable region frameworks with full retention of binding and T-cell mediated cytotoxic activity. To address potential manufacturability concerns, multiple approaches were taken in parallel to optimize and de-risk the two antibody variable regions. These approaches included structure-guided rational mutagenesis and phage display-based optimization, focusing on improving stability, reducing polyreactivity and self-association potential, removing chemical liabilities and proteolytic cleavage sites, and de-risking immunogenicity. Employing rapid library construction methods as well as automated phage display and high-throughput protein production workflows enabled efficient generation of an optimized bispecific antibody with desirable manufacturability properties, high stability, and low nonspecific binding. Proteolytic cleavage and deamidation in complementarity-determining regions were also successfully addressed. Collectively, these improvements translated to a molecule with potent single-agent in vivo efficacy in a tumor cell line adoptive transfer model and a cynomolgus monkey pharmacokinetic profile (half-life>4.5 days) suitable for clinical development. Clinical evaluation of PF-07062119 is ongoing.