Assessing deviations for HPCs obtained during COVID-19 (ADHOC): Evaluating impact of the COVID-19 pandemic on cellular therapy products and processes, the BEST collaborative study.

BACKGROUND: The success of allogeneic hematopoietic stem cell transplantation is dependent on a world-wide network of collection centers providing donations that predominantly have been infused as fresh cells. The logistics chain that supports the just-in-time delivery model for stem cell and immunotherapy products was severely stressed by the COVID pandemic, and in early 2020 a number of national and international bodies recommended that cells should be cryopreserved at the collection or transplant center to avoid interruptions in their acquisition or delivery to patients who had started conditioning. STUDY DESIGN: To assess the potential consequences of such pandemic-related deviations to normal practice, we surveyed nine international laboratories to determine if the characteristics or transplant outcomes of allogeneic stem cell donations differed in the immediate periods before and after the switch to routine cryopreservation. RESULTS: Nine centers on two continents provided data for 72 HSC donations just before, and 71 just after, switching to cryopreservation for allogeneic HSC products. No statistically significant differences between the period before and after cryopreservation were noted for time from product collection to receipt, product temperature at receipt, or CD34+ cell viability at receipt. There was an indication of slower absolute neutrophil count recovery after cryopreservation was required (mean time of 15 vs. 17.6 days). DISCUSSION: While there were no apparent changes to most parameters studied, there was an indication of slower neutrophil engraftment that will need to be examined in larger, longer term studies.

Transfusion support for patients with sickle cell disease.

Red blood cell (RBC) transfusion is an essential treatment for many patients with sickle cell disease (SCD), whose RBCs express hemoglobin S (HbS), a mutated form of hemoglobin A (HbA). Transfusion goals include increasing blood oxygen carrying capacity and decreasing the relative amount of HbS to HbA to mitigate vaso-occlusion in small blood vessels. In situations where correction of severe anemia and reduction in HbS may be achieved without removal of RBCs, simple transfusion may be utilized. Partial manual RBC exchange, which removes blood containing HbS by phlebotomy and replaces with donor blood transfusion sequentially allows for larger changes in the ratio of HbS to HbA when compared to simple transfusion. Automated RBC exchange by apheresis is useful in situations where a rapid and drastic HbS reduction is indicated. Vascular access is an important consideration for transfusion. Although peripheral access may be sufficient, central venous catheters and implantable venous access devices may be necessary for adequate access over time. Blood bank considerations include adequate RBC antigen matching to mitigate the risk of RBC alloimmunization, of which patients with SCD are at risk of developing. Transfusion may be utilized in efforts to intervene in the evolution of potentially life-threatening complications of SCD such as acute stroke, severe acute anemia and acute chest syndrome. Transfusion is also useful in several non-acute settings, such as stroke prevention, pregnancy, pre-surgery, and transfusion support for curative therapies. Individualized treatment plans are an essential component of patient care. Continuous evaluation of clinical indications and evolution of guidelines will continue to optimize care for patients with SCD.

Hospital red blood cell and platelet supply and utilization from March to December of the first year of the COVID-19 pandemic: The BEST collaborative study.

BACKGROUND: At the start of the coronavirus disease 2019 (COVID-19) pandemic, widespread blood shortages were anticipated. We sought to determine how hospital blood supply and blood utilization were affected by the first wave of COVID-19. STUDY DESIGN AND METHODS: Weekly red blood cell (RBC) and platelet (PLT) inventory, transfusion, and outdate data were collected from 13 institutions in the United States, Brazil, Canada, and Denmark from March 1st to December 31st of 2020 and 2019. Data from the sites were aligned based on each site's local first peak of COVID-19 cases, and data from 2020 (pandemic year) were compared with data from the corresponding period in 2019 (pre-pandemic baseline). RESULTS: RBC inventories were 3% lower in 2020 than in 2019 (680 vs. 704, p < .001) and 5% fewer RBCs were transfused per week compared to 2019 (477 vs. 501, p < .001). However, during the first COVID-19 peak, RBC and PLT inventories were higher than normal, as reflected by deviation from par, days on hand, and percent outdated. At this time, 16% fewer inpatient beds were occupied, and 43% fewer surgeries were performed compared to 2019 (p < .001). In contrast to 2019 when there was no correlation, there was, in 2020, significant negative correlations between RBC and PLT days on hand and both percentage occupancy of inpatient beds and percentage of surgeries performed. CONCLUSION: During the COVID-19 pandemic in 2020, RBC and PLT inventories remained adequate. During the first wave of cases, significant decreases in patient care activities were associated with excess RBC and PLT supplies and increased product outdating.

Considerations for immune effector cell therapy collections: a white paper from the American Society for Apheresis.

BACKGROUND AIMS: This white paper was developed to provide leukapheresis guidance for the collection of mononuclear cells from adult and pediatric patients who are destined for immune effector cell (IEC) therapies for commercial and research applications. Currently, there is considerable variability in leukapheresis processes and limited published information regarding best practices relevant to new cellular therapies, especially IECs. Herein the authors address critical leukapheresis questions in five domains to help guide consistent collection processes and ensure high-quality products. The first four domains are onboarding, pre-collection, collection and post-collection, with protocol feasibility, preparation, care and follow-up of the patient/donor at each step, respectively, and technical considerations during collection. The fifth domain of quality assurance focuses on ensuring product potency, purity, safety and auditing. METHODS: The American Society for Apheresis (ASFA) Clinical Applications Committee (IEC Therapy Subcommittee) was charged by the society's board of directors with working collaboratively with other ASFA committees and organizations, including the Foundation for the Accreditation of Cellular Therapy, Association for the Advancement of Blood and Biotherapies, American Society for Transplantation and Cellular Therapy, National Marrow Donor Program and International Society for Cell & Gene Therapy, to develop guidelines regarding leukapheresis collection of cells destined for the manufacture of IEC therapies. After a review of the literature and discussion with members of the involved committees and various institutions, a draft guidance was created and circulated for comment and revision. RESULTS: Critical aspects of apheresis that could affect the quality and quantity of the leukapheresis product were identified. These areas were then discussed and reviewed. After consensus, the best practice guidelines were proposed and accepted. CONCLUSIONS: In the current era of rapid growth of IEC therapies, it is important to address critical leukapheresis steps to provide high-quality products and more consistent practices and to eliminate redundant efforts.

Lack of defined apheresis collection criteria in publicly available CAR-T cell clinical trial descriptions: Comprehensive review of over 600 studies.

BACKGROUND: Chimeric antigen receptor T (CAR-T) cell successes have encouraged continued clinical study. Apheresis collection of starting material for CAR-T cell therapy product manufacturing is critical but described approaches suggest variability and clinical guidelines are currently lacking. The goal of this study was to gather and assess variability in apheresis collection descriptions in publicly available CAR T-cell therapy clinical trials. STUDY DESIGN: We searched clinicaltrials.gov (a publicly available clinical trial database) for "chimeric antigen receptor T cells" on July 01, 2020 and studies accessed July 30, 2020-August 15, 2020. Data collected included date posted, study characteristics, apheresis mentions (number, location, and context), laboratory parameters and transfusion allowances. Apheresis context was analyzed using a qualitative inductive approach of grounded theory method with open coding. Text was classified into 37 context codes, grouped into 12 categories, and then consolidated into patient, procedure, product, and miscellaneous themes. RESULTS: Apheresis was mentioned 1044 times in 322 (51.9%) of 621 total studies. Laboratory parameters mentioned included white blood cells (100 studies), absolute neutrophil count (220 studies), absolute lymphocyte count (102 studies), CD3+ cell (38 studies), hemoglobin (233 studies, 54 studies specified transfusion allowance), and platelet (269 studies, 48 studies specified transfusion allowance). CONCLUSIONS: Apheresis collection of CAR-T cell products is not well-defined in clinical study descriptions and the context is inconsistent. Laboratory parameters useful for apheresis collection are variably present and do not consistently align with current practices. Further exploration, and clinical guideline development will encourage alignment of apheresis collections for CAR-T cell products.

Volume determination methods for hematopoietic progenitor cell products collected by apheresis.

BACKGROUND AIMS: CD34+ cell count of hematopoietic progenitor cell products is often first determined using a product sample, with the final reported cell count obtained by multiplying cell count from the sample by the total product volume. Product volume may be determined by apheresis instruments used for collection or calculated based on specific gravity (SG). Here the authors sought to determine the discrepancies between these methods and the impact on patient care. METHODS: A total of 262 products collected from 176 donors by apheresis were retrospectively reviewed. Volumes calculated by apheresis instruments were compared with volumes calculated based on SG. CD34+ cell/kg doses based on volumes from apheresis instruments and SG were also compared. Furthermore, among 42 patients who required multiple collections, the authors determined whether different calculation methods would have changed the number of procedures required. RESULTS: The volumes for 253 products (96.6%) and CD34+ cell/kg doses for 257 products (98.1%) generated from apheresis instruments and SG were similar. Products with discrepant volumes when calculated using different methods were not associated with delayed engraftment. Forty patients who underwent multiple collections (95.2%) were under their collection goals during their first collection and would have required multiple procedures regardless of which method was used to calculate product volumes. CONCLUSIONS: Volumes determined based on SG did not provide a clear benefit over volumes determined by apheresis instruments. Hence, variation in volume calculation methods across different laboratories is likely to lead to minimal impact on patient care.

IFNα Augments Clinical Efficacy of Regulatory T-cell Depletion with Denileukin Diftitox in Ovarian Cancer.

PURPOSE: Immunotherapy treats some cancers, but not ovarian cancer. Regulatory T cells (Tregs) impede anti-ovarian cancer immunity but effective human Treg-directed treatments are lacking. We tested Treg depletion with denileukin diftitox (DD) ± IFNα as ovarian cancer immunotherapy. PATIENTS AND METHODS: Mice with syngeneic ID8 ovarian cancer challenge were treated with DD, IFNα, or both. The phase 0/I trial tested one dose-escalated DD infusion for functional Treg reduction, safety, and tolerability. The phase II trial added IFNα2a to DD if DD alone failed clinically. RESULTS: DD depleted Tregs, and improved antitumor immunity and survival in mice. IFNα significantly improved antitumor immunity and survival with DD. IFNα did not alter Treg numbers or function but boosted tumor-specific immunity and reduced tumor Treg function with DD by inducing dendritic cell IL6. DD alone was well tolerated, depleted functional blood Tregs and improved immunity in patients with various malignancies in phase 0/I. A patient with ovarian cancer in phase 0/I experienced partial clinical response prompting a phase II ovarian cancer trial, but DD alone failed phase II. Another phase II trial added pegylated IFNα2a to failed DD, producing immunologic and clinical benefit in two of two patients before a DD shortage halt. DD alone was well tolerated. Adding IFNα increased toxicities but was tolerable, and reduced human Treg numbers in blood, and function through dendritic cell-induced IL6 in vitro. CONCLUSIONS: Treg depletion is clinically useful but unlikely alone to cure ovarian cancer. Rational treatment agent combinations can salvage clinical failure of Treg depletion alone, even when neither single agent provides meaningful clinical benefit.

A multicenter evaluation of heterogeneity in cellular therapy processing laboratory procedure times to assess workload capacity.

BACKGROUND: Growth in size and complexity of clinical hematopoietic progenitor cell (HPC) transplant programs necessitates parallel increases in cellular therapy laboratory (CTL) workload. Typically individually developed, HPC product processing is labor and time intensive. Variation in procedure type and numbers across CTLs complicates direct comparisons, and benchmark data are not readily available. STUDY DESIGN AND METHODS: Studies were undertaken at seven CTLs. Transplant volume and staff numbers were determined. Staff recorded time performing tasks broken down into steps: paperwork, product acceptance, transport/infusion, processing, and cryopreservation. Times were added to obtain total times for 15 common CTL procedures. RESULTS: Annual transplant volume ranged from 53.4 to 463.2, with products processed by a range of 2 to 10 dedicated CTL staff. Paperwork time constituted 23.7% to 62.3% total time; product processing time accounted for 1.8 (for National Marrow Donor Program product receipt) to 62.6% (for red blood cell reduction of allogeneic HPC products from bone marrow) of total processing time. Mean time for 15 procedures ranged from 1.27 to 8.28 hours (standard deviation range, 0.35-2.71 hr). Mean time for products from bone marrow versus peripheral blood was 6.6 ± 2.0 versus 5.5 ± 1.1 hours (p = 0.02). Cryopreservation (6.5 ± 1.6 vs. 4.4 ± 0.85 hr; p < 0.01) and manipulation (6.4 ± 1.5 vs. 4.4 ± 0.85 hr; p < 0.01) added time. CONCLUSION: CTL procedures are time intensive, with wide intra- and inter-CTL variation. Paperwork accounted for substantial portion of total time across procedures. Bone marrow source, cryopreservation, and manipulation contributed to longer times. These findings provide concrete data on which to build regarding CTL workload capacity.

Optimizing management of replacement fluids for therapeutic plasma exchange: Use of an automated mathematical model to predict post-procedure fibrinogen and antithrombin levels in high-risk patients.

BACKGROUND: Therapeutic plasma exchange (TPE) utilizes an extracorporeal circuit to remove pathologic proteins causing serious illness. When processing a patient's entire blood volume through an extracorporeal circuit, proteins responsible for maintaining hemostatic system homeostasis can reach critically low levels if replacement fluid types and volumes are not carefully titrated, which may increase complications. METHODS: The charts from 27 patients undergoing 46 TPE procedures were reviewed to evaluate the accuracy of our predictive mathematical model, utilizing the following patient information: weight, hematocrit, pre- and post-TPE factor levels (fibrinogen, n = 46, and antithrombin, n = 23), process volume and volumes of fluids (eg, plasma, albumin, and normal saline) administered during TPE and adverse events during and after TPE. RESULTS: Altogether, 25% of patients experienced minor adverse events that resolved spontaneously or with management. There were no bleeding or thrombotic complications. The mean difference between predicted and measured post-TPE fibrinogen concentrations was -0.29 mg/dL (SD ±23.0, range -59 to 37), while percent difference between measured and predicted fibrinogen concentration was 0.94% (SD ±10.8, range of -22 to 19). The mean difference between predicted and measured post-TPE antithrombin concentrations were 0.89% activity (SD ±10.0, range -23 to 14), while mean percent difference between predicted and measured antithrombin concentrations was 3.87% (SD ±14.5, range -25 to 38). CONCLUSIONS: Our model reliably predicts post-TPE fibrinogen and antithrombin concentrations, and may help optimize patient management and attenuate complications.

Ensuring safety of the blood supply in the United States: Donor screening, testing, emerging pathogens, and pathogen inactivation.

Safety of the blood supply has been a critical aspect of the transfusion medicine field since its inception, including infections that can be passed to a blood product recipient. Reactive efforts to identify potentially infected blood products are used throughout the blood donation process and afterward. Before donation, potential donors are provided educational materials about infection risks, examined and then screened through a series of questions that help temporarily, permanently, or indefinitely defer donors who could harbor acute and/or chronic infections. During donation, aseptic technique and diversion pouches reduce the potential to introduce bacteria into the blood product. Before transfusion, the blood products are tested for several infectious diseases by serology, nucleic acid testing, or a combination. During transfusion, the patient is monitored closely, and suspected transfusion reactions should be reported and investigated. The FDA regularly publishes guidance documents to incorporate knowledge gained regarding transfusion-transmitted infections, so that information can be shared and practices updated so that transfusion-related patient care can be optimized over time. Pathogen reduction processes are being developed and deployed that provide a proactive approach to both recognized and emerging pathogens.

More efficient exchange of sickle red blood cells can be achieved by exchanging the densest red blood cells: An ex vivo proof of concept study.

BACKGROUND: In sickle cell disease (SCD), red blood cells (RBCs) containing hemoglobin S can be denser than RBCs containing wild-type hemoglobin, especially when dehydrated. We hypothesize that targeting denser RBCs during red blood cell (RBC) exchange for SCD could result in more efficient removal of dehydrated, sickled RBCs and preservation of non-sickled RBCs. STUDY DESIGN AND METHODS: Waste products from RBC exchanges for SCD were used as "simulated patients". One RBC volume was exchanged using ABO-compatible blood. The apheresis instrument was programmed to exchange the entire RBC layer by indicating the hematocrit (control), or the bottom half by indicating the hematocrit was half the hematocrit (experimental), with or without subsequent transfusion. Hemoglobin S levels, and complete blood counts were measured. RESULTS: Hemoglobin S levels were lower after the modified versus control RBC exchange (post-RBC exchange mean 4.96% and 11.27%); total hemoglobin S amounts were also lower (mean 19.27 and 58.29 mL of RBCs). Mean RBC density decreased after the modified RBC exchange by 8.86%. Hematocrit decreased in the modified RBC exchange by 36.37%, with partial correction by direct transfusion following a truncated RBC exchange. CONCLUSIONS: Targeting denser RBCs in RBC exchange enhanced hemoglobin S removal and decreased RBC density. Further development of this ex vivo model could potentially allow for: 1) improved reduction in hemoglobin S levels (allowing for longer periods between RBC exchange or maintained lower levels), or 2) achievement of previous goal hemoglobin S levels with fewer donor units (reducing alloimmunization risk and improving blood utilization).

Immunotherapy Using Chimeric Antigen Receptor-Engineered T Cells: A Novel Cellular Therapy with Important Implications for the Clinical Laboratory.

BACKGROUND: We have entered a new era of cancer therapy, with a number of immune-based therapies already used clinically as a standard of care. Adoptive cellular immunotherapy using T cells genetically modified with chimeric antigen receptors (CAR-T cells) represents a novel therapeutic approach. CAR-T cells have produced clinical responses in B-cell malignancies that are otherwise refractory to conventional therapies. Two CAR-T cell therapies obtained regulatory approval in 2017, with many more of these therapies under clinical development. CONTENT: This review focuses on the current state of adoptive cellular immunotherapy, specifically CAR-T cells, in the clinic and how this therapy differs from traditional small molecule and biologic therapies. Areas in which the clinical laboratory is affected by these novel therapies are discussed. Opportunities for the clinical laboratory to help guide these therapies are also highlighted. SUMMARY: The clinical laboratory will play an integral role in the care of patients undergoing adoptive cellular therapy with engineered T cells. There are many ways that this new therapeutic approach affects the clinical laboratory, and the clinical laboratory will likely play a critical role in managing patients that are treated with CAR-T cell therapy.

Vascular access for red blood cell exchange.

Red blood cell exchange is the process of removing red blood cells from a patient and replacing them with donated blood using either automated or manual techniques. Red blood cell exchange is a well-recognized and effective therapy for many red blood cell-related diseases, especially sickle cell disease. However, decisions regarding the best methods for vascular access are not intuitive and must account for the patient's clinical condition, complication risks, and lifestyle, especially in the context of long-term vascular access. In this review, we discuss the recognized indications for red blood cell exchange, considerations for the selection of exchange modality and vascular access, and recommendations for the appropriate care and prevention of risks associated with vascular access.

Novel gene and cellular therapy approaches for treating HIV.

Advances in HIV drug therapy have drastically decreased mortality and significantly improved quality of life for HIV infected patients since the early days of the epidemic. However, HIV drug-resistance, drug toxicities, therapy adherence, and the need for life-long treatment remain major challenges that continue to contribute to HIV-related global health concerns. Recent advances in cancer immunotherapy have proven the potency of cellular gene therapies. An ever-growing toolbox of methods of gene manipulation, cell modification, and clinical cell manufacturing, will enable moving beyond continuous drug therapy for more effective and durable treatments, including the possibility of inducing permanent resistance to HIV. These approaches, which target both host and viral factors, capitalize on points of vulnerability in the virus life cycle. Cellular and gene therapy has the potential to be an effective one-time therapy with less toxicity. Here, we review several promising strategies currently in pre-clinical development and clinical trials.

TgMAPK1 is a Toxoplasma gondii MAP kinase that hijacks host MKK3 signals to regulate virulence and interferon-γ-mediated nitric oxide production.

The parasite Toxoplasma gondii controls tissue-specific nitric oxide (NO), thereby augmenting virulence and immunopathology through poorly-understood mechanisms. We now identify TgMAPK1, a Toxoplasma mitogen-activated protein kinase (MAPK), as a virulence factor regulating tissue-specific parasite burden by manipulating host interferon (IFN)-γ-mediated inducible nitric oxide synthase (iNOS). Toxoplasma with reduced TgMAPK1 expression (TgMAPK1(lo)) demonstrated that TgMAPK1 facilitates IFN-γ-driven p38 MAPK activation, reducing IFN-γ-generated NO in an MKK3-dependent manner, blunting IFN-γ-mediated parasite control. TgMAPK1(lo) infection in wild type mice produced ≥ten-fold lower parasite burden versus control parasites with normal TgMAPK1 expression (TgMAPK1(con)). Reduced parasite burdens persisted in IFN-γ KO mice, but equalized in normally iNOS-replete organs from iNOS KO mice. Parasite MAPKs are far less studied than other parasite kinases, but deserve additional attention as targets for immunotherapy and drug discovery.

Mitigating age-related immune dysfunction heightens the efficacy of tumor immunotherapy in aged mice.

Although cancer tends to affect the elderly, most preclinical studies are carried out in young subjects. In this study, we developed a melanoma-specific cancer immunotherapy that shows efficacy in aged but not young hosts by mitigating age-specific tumor-associated immune dysfunction. Both young and aged CD4(+)CD25(hi) regulatory T cells (Treg) exhibited equivalent in vitro T-cell suppression and tumor-associated augmentation in numbers. However, denileukin diftitox (DT)-mediated Treg depletion improved tumor-specific immunity and was clinically effective only in young mice. DT-mediated Treg depletion significantly increased myeloid-derived suppressor cell (MDSC) numbers in aged but not young mice, and MDSC depletion improved tumor-specific immunity and reduced tumor growth in aged mice. Combining Treg depletion with anti-Gr-1 antibody was immunologically and clinically more efficacious than anti-Gr-1 antibody alone in aged B16-bearing mice, similar to Treg depletion alone in young mice. In contrast, DT increased MDSCs in young and aged mice following MC-38 tumor challenge, although effects were greater in aged mice. Anti-Gr-1 boosted DT effects in young but not aged mice. Aged antitumor immune effector cells are therefore competent to combat tumor when underlying tumor-associated immune dysfunction is appropriately mitigated, but this dysfunction varies with tumor, thus also varying responses to immunotherapy. By tailoring immunotherapy to account for age-related tumor-associated immune dysfunctions, cancer immunotherapy for aged patients with specific tumors can be remarkably improved.

Aged regulatory T cells protect from autoimmune inflammation despite reduced STAT3 activation and decreased constraint of IL-17 producing T cells.

Regulatory T cells (Tregs) are specialized CD4(+) T lymphocytes helping defend against autoimmunity and inflammation. Although age is associated with increased inflammation and autoimmunity, few reports address age effects of immune regulation or auto-aggressive T cells. We show here that young and aged naïve CD4(+) T cells are equivalently auto-aggressive in vivo in T cell-driven autoimmune colitis. Young and aged CD4(+) Tregs equally suppressed age-matched T cell proliferation in vitro and controlled clinical and pathologic T cell-driven autoimmune colitis, suggesting equivalent regulatory function. However, whereas young and aged CD4(+) Tregs suppressed interferon (IFN)-γ(+) T cells equivalently in this model, aged CD4(+) Tregs unexpectedly failed to restrain interleukin (IL)-17(+) T cells. Nonetheless, young and aged CD4(+) Tregs equally restrained IL-17(+) T cells in vivo during acute inflammation, suggesting a chronic inflammation-related defect in aged CD4(+) Tregs. In support, aged Tregs expressed reduced STAT3 activation, a defect associated with poor IL-17-producing T cell restraint. Aged naïve mice had markedly increased programmed death (PD)-1(+) T cells, but these exhibited no significant auto-aggressive or regulatory functions in T cell-driven colitis. Young CD8(+) CD122(-) T cells induce autoimmune bone marrow failure, but we show that aged CD8(+) CD122(-) T cells do not. These data demonstrate no apparent age-related increase in auto-aggressive T cell behavior, but disclose previously unrecognized functional defects in aged CD4(+) Tregs during chronic inflammation. IL-17 can be inflammatory and contributes to certain autoimmune disorders. Reduced aged Treg function during chronic inflammation and reduced IL-17 restraint could contribute to age-related inflammation or autoimmunity.