Apoptosis: a Janus bifrons in T-cell immunotherapy.

Immunotherapy has revolutionized the treatment of cancer. In particular, immune checkpoint blockade, bispecific antibodies, and adoptive T-cell transfer have yielded unprecedented clinical results in hematological malignancies and solid cancers. While T cell-based immunotherapies have multiple mechanisms of action, their ultimate goal is achieving apoptosis of cancer cells. Unsurprisingly, apoptosis evasion is a key feature of cancer biology. Therefore, enhancing cancer cells' sensitivity to apoptosis represents a key strategy to improve clinical outcomes in cancer immunotherapy. Indeed, cancer cells are characterized by several intrinsic mechanisms to resist apoptosis, in addition to features to promote apoptosis in T cells and evade therapy. However, apoptosis is double-faced: when it occurs in T cells, it represents a critical mechanism of failure for immunotherapies. This review will summarize the recent efforts to enhance T cell-based immunotherapies by increasing apoptosis susceptibility in cancer cells and discuss the role of apoptosis in modulating the survival of cytotoxic T lymphocytes in the tumor microenvironment and potential strategies to overcome this issue.

Modulation of BCL-2 in Both T Cells and Tumor Cells to Enhance Chimeric Antigen Receptor T-cell Immunotherapy against Cancer.

Chimeric antigen receptor T-cell (CART) immunotherapy led to unprecedented responses in patients with refractory/relapsed B-cell non-Hodgkin lymphoma (NHL); nevertheless, two thirds of patients experience treatment failure. Resistance to apoptosis is a key feature of cancer cells, and it is associated with treatment failure. In 87 patients with NHL treated with anti-CD19 CART, we found that chromosomal alteration of B-cell lymphoma 2 (BCL-2), a critical antiapoptotic regulator, in lymphoma cells was associated with reduced survival. Therefore, we combined CART19 with the FDA-approved BCL-2 inhibitor venetoclax and demonstrated in vivo synergy in venetoclax-sensitive NHL. However, higher venetoclax doses needed for venetoclax-resistant lymphomas resulted in CART toxicity. To overcome this limitation, we developed venetoclax-resistant CART by overexpressing mutated BCL-2(F104L), which is not recognized by venetoclax. Notably, BCL-2(F104L)-CART19 synergized with venetoclax in multiple lymphoma xenograft models. Furthermore, we uncovered that BCL-2 overexpression in T cells intrinsically enhanced CART antitumor activity in preclinical models and in patients by prolonging CART persistence. SIGNIFICANCE: This study highlights the role of BCL-2 in resistance to CART immunotherapy for cancer and introduces a novel concept for combination therapies-the engineering of CART cells to make them resistant to proapoptotic small molecules, thereby enhancing the therapeutic index of these combination therapies. This article is highlighted in the In This Issue feature, p. 2221.

Therapeutic errors captured by the New Zealand National Poisons Centre: a retrospective audit.

INTRODUCTION Medication errors are one important cause of harm to patients. Information about medication errors can be obtained from diverse sources, including databases administered by poisons centres as part of their routine operation. AIM The aim of this study was to describe the data regarding therapeutic errors captured by the New Zealand National Poisons Centre (NZNPC). METHODS A retrospective study of calls made to the NZNPC between 1 September 2016 and 31 August 2018 was conducted, which involved human patients and were classified as 'therapeutic error' in the NZNPC database. Variables extracted and analysed included the demographics of the individual, the substance(s) involved, and site of exposure. RESULTS During the study period, a total of 43,578 calls were received by the NZNPC, including 5708 (13%) that were classified as 'therapeutic error'. Just over half of the exposures occurred in females, 3197 (56%) and 4826 (85%) of the calls involved a single substance. All age groups were affected and 2074 (37%) of the calls were related to children aged <12 years. A residential environment (n=5568, 97%) was the site of exposure for almost all reported therapeutic errors, most commonly in the patient's own home (n=5207, 91%). DISCUSSION This study provides insights into therapeutic error-related calls to the NZNPC. Almost all errors occurred in the residential setting. Over one-third of the calls involved children. Enhanced data capture and classification methods are needed to determine the types of errors and their possible causes to better inform prevention efforts.

Evaluation of Weight Thresholds for Pediatric Patients to Use Adult Dosage of Therapeutic Monoclonal Antibodies.

With increasing interest in enrolling adolescent patients in adult trials, a question often arises: when can pediatric patients use adult dosages? For currently approved therapeutic monoclonal antibodies (mAbs) with equivalent adult and pediatric indications, body weight thresholds for pediatric patients to receive adult doses vary from 30 to 75 kg. Our objective is to determine if a consistent weight threshold can be recommended for therapeutic mAbs with wide therapeutic windows. Simulations were run to predict exposure using a population pharmacokinetic model describing the typical PK characteristics of a mAb with linear elimination. Simulated steady-state areas under the concentration-time curves (AUCss ) were compared between pediatric and adult populations. Exponent values of 0.50, 0.75, and 1.0 for the allometric relationship of weight on clearance were also evaluated. Following administration of the same fixed adult dosage in pediatric subjects above a given threshold, median AUCss in the pediatric subjects increased with decreasing weight thresholds. Pediatrics with a minimum weight of 40 kg had median AUCss within 20% to 30% above adult median AUCss when the reference adult population had a median weight ≤80 kg. Higher relative pediatric exposures were seen in lower-weight pediatric subjects when the weight exponent on clearance was >0.75. Simulations suggested that a weight threshold of 40 kg could generally be considered for pediatric subjects to receive the adult dosage for therapeutic mAbs with linear pharmacokinetics. Weight threshold selection should be based on considerations of therapeutic index of the drug product, weight distribution of the reference adult population, and magnitude of weight effect on pharmacokinetic parameters.

Femur Rotation Increases Patella Cartilage Stress in Females with Patellofemoral Pain.

PURPOSE: This study aimed to test the hypothesis that internal rotation of the femur increases patellofemoral joint stress in persons with patellofemoral pain (PFP). METHODS: Patella cartilage stress profiles of nine female participants with PFP were obtained during squatting using subject-specific finite element (FE) models of the patellofemoral joint (15° and 45° of knee flexion). Input parameters for the FE model included joint geometry, quadriceps muscle forces during squatting, and weight-bearing patellofemoral joint kinematics. The femur of each model was then internally rotated 5° and 10° along its long axis beyond that of the natural degree of rotation. Using a nonlinear FE solver, quasistatic loading simulations were performed to quantify patellofemoral joint stress. RESULTS: Compared with those at the natural position of the femur, mean hydrostatic pressure and mean octahedral shear stress were significantly higher when the femur was internally rotated 5° and 10°. No significant differences in stress variables were observed when the femur was rotated from 5° to 10°. These findings were consistent across both knee flexion angles (15° and 45°). CONCLUSIONS: The finding of elevated hydrostatic pressure and octahedral shear stress with internal rotation of the femur supports the premise that females with PFP who exhibit abnormal hip kinematics may be exposed to elevated patellofemoral joint stress.

Failure locus of the anterior cruciate ligament: 3D finite element analysis.

Anterior cruciate ligament (ACL) disruption is a common injury that is detrimental to an athlete's quality of life. Determining the mechanisms that cause ACL injury is important in order to develop proper interventions. A failure locus defined as various combinations of loadings and movements, internal/external rotation of femur and valgus and varus moments at a 25(o) knee flexion angle leading to ACL failure was obtained. The results indicated that varus and valgus movements were more dominant to the ACL injury than femoral rotation. Also, Von Mises stress in the lateral tibial cartilage during the valgus ACL injury mechanism was 83% greater than that of the medial cartilage during the varus mechanism of ACL injury. The results of this study could be used to develop training programmes focused on the avoidance of the described combination of movements which may lead to ACL injury.

Effect of frontal plane tibiofemoral angle on the stress and strain at the knee cartilage during the stance phase of gait.

Subject-specific three-dimensional finite element models of the knee joint were created and used to study the effect of the frontal plane tibiofemoral angle on the stress and strain distribution in the knee cartilage during the stance phase of the gait cycle. Knee models of three subjects with different tibiofemoral angle and body weight were created based on magnetic resonance imaging of the knee. Loading and boundary conditions were determined from motion analysis and force platform data, in conjunction with the muscle-force reduction method. During the stance phase of walking, all subjects exhibited a valgus-varus-valgus knee moment pattern with the maximum compressive load and varus knee moment occurring at approximately 25% of the stance phase of the gait cycle. Our results demonstrated that the subject with varus alignment had the largest stresses at the medial compartment of the knee compared to the subjects with normal alignment and valgus alignment, suggesting that this subject might be most susceptible to developing medial compartment osteoarthritis (OA). In addition, the magnitude of stress and strain on the lateral cartilage of the subject with valgus alignment were found to be larger compared to subjects with normal alignment and varus alignment, suggesting that this subject might be most susceptible to developing lateral compartment knee OA.

The effect of the frontal plane tibiofemoral angle and varus knee moment on the contact stress and strain at the knee cartilage.

Subject-specific models were developed and finite element analysis was performed to observe the effect of the frontal plane tibiofemoral angle on the normal stress, Tresca shear stress and normal strain at the surface of the knee cartilage. Finite element models were created for three subjects with different tibiofemoral angle and physiological loading conditions were defined from motion analysis and muscle force mathematical models to simulate static single-leg stance. The results showed that the greatest magnitude of the normal stress, Tresca shear stress and normal strain at the medial compartment was for the varus aligned individual. Considering the lateral knee compartment, the individual with valgus alignment had the largest stress and strain at the cartilage. The present investigation is the first known attempt to analyze the effects of tibiofemoral alignment during single-leg support on the contact variables of the cartilage at the knee joint. The method could be potentially used to help identify individuals most susceptible to osteoarthritis and to prescribe preventive measures.

The combined effect of frontal plane tibiofemoral knee angle and meniscectomy on the cartilage contact stresses and strains.

Abnormal tibiofemoral alignment can create loading conditions at the knee that may lead to the initiation and progression of knee osteoarthritis (OA). The degenerative changes of the articular cartilage may occur earlier and with greater severity in individuals with abnormal frontal plane tibiofemoral alignment who undergo a partial or total meniscectomy. In this investigation, subject specific 3D finite element knee models were created from magnetic resonance images of two female subjects to study the combined effect of frontal plane tibiofemoral alignment and total and partial meniscectomy on the stress and strain at the knee cartilage. Different amounts of medial and lateral meniscectomies were modeled and subject specific loading conditions were determined from motion analysis and force platform data during single-leg support. The results showed that the maximum stresses and strains occurred on the medial tibial cartilage after medial meniscectomy but a greater percentage change in the contact stresses and strains occurred in the lateral cartilage after lateral meniscectomy for both subjects due to the resultant greater load bearing role of the lateral meniscus. The results indicate that individual's frontal plane knee alignment and their unique local force distribution between the cartilage and meniscus play an important role in the biomechanical effects of total and partial meniscectomy.

DNA analysis of digested tomato seeds in stomach contents.

Examination of stomach contents is one of the important steps in medical legal autopsy. Vegetative materials such as stems, roots, and seeds in stomach contents can be valuable evidence for providing investigative leads in death investigation. Currently, the identification of plant materials relies on microscopic and morphologic examination. We have found that many seeds are often protected from acid degradation during stomach digestion by their tough exterior seed coat. Tomato seeds were selected as a model system to assess DNA analysis and plant variety marker identification. The DNA-amplified fragment length polymorphism method was performed to determine if the DNA obtained from single seeds could be used for PCR analysis. From the amplified fragment length polymorphism results, some candidate markers for individualizing seeds from morphologically distinct tomatoes were identified. These data on DNA analysis of tomato seeds indicate amplified fragment length polymorphism is a viable procedure for the individualization of seeds from stomach contents in forensic investigations.