Zubair, Abba C

Foundation models are reshaping computational pathology by enabling scalable task-agnostic representations of histopathological whole-slide images (WSIs). Unlike earlier task-specific deep learning systems, pathology foundation models (PFMs) leverage massive whole-slide image repositories and self-supervised Vision Transformer architectures to achieve broad generalization and few-shot adaptability. Their evolution reflects a shift from weakly supervised approaches such as Clustering-Constrained Attention Multiple Instance Learning (CLAM) and hierarchical architectures such as Hierarchical Image Pyramid Transformer (HIPT) to large-scale efforts including foundation models, UNI, Virchow, Phikon, CONtrastive learning from Captions for Histopathology (CONCH), GigaPath, H-Optimus, Transformer-Based Pathology Image and Text Alignment Network (TITAN), and the Mayo Clinic Atlas. These models demonstrate impressive performance across diagnostic and prognostic benchmarks while also opening pathways for multimodal integration with genomics and clinical data. Yet significant barriers remain including inconsistent generalization across institutions, interpretability lagging behind clinical needs, and slow integration into routine laboratory workflows. Certain domains of anatomic pathology such as cytopathology, transplant pathology, frozen sections, and rare tumor subtypes remain particularly resistant to current models. Here, we review the development of PFMs, critically evaluate their strengths and limitations, and outline priorities for their safe and effective clinical translation. We argue that the next phase of PFM development will depend on rigorous benchmarking, pathologist-in-the-loop deployment, and multimodal fusion ensuring these models evolve from research tools into clinically robust systems.

Extracellular vesicles derived from mesenchymal stem cells (MSC-EVs) exhibit great therapeutic potential in ischemia-associated conditions and diseases such as myocardial infarction, ischemic stroke, and wound healing. Enhancing the therapeutic efficacy of MSC-EVs could advance their clinical application. Diverse cargos (proteins, mRNA, microRNA, etc.) in MSC-EVs contribute to the therapeutic effects in various diseases. Vascular endothelial growth factor (VEGF) is one of the primary driving molecules in promoting angiogenesis and protecting endothelial cells lining blood vessels from apoptosis. In this study, we explored the feasibility of engineering parent MSCs with VEGF mRNA to potentiate therapeutic effects of their derived EVs. We first detected elevated levels of VEGF mRNA and protein in transfected MSCs and demonstrated the bioactivity of secreted VEGF by an angiogenesis assay. Furthermore, EVs derived from VEGF mRNA-engineered MSCs (VEGF-MSC-EVs) contained high levels of VEGF mRNA and protein and showed superior ability to protect human umbilical vein endothelial cells (HUVECs) from apoptosis compared to EVs derived from control MSCs (control MSC-EVs). To our knowledge, this is the first report demonstrating that VEGF-MSC-EVs boost therapeutic efficacy by promoting endothelial cell survival. Our findings offer a novel approach for cell-free therapy in ischemia-associated conditions and diseases.

Galactic cosmic ray (GCR) radiation is a major barrier to human space exploration beyond Earth’s magnetic field protection. Mesenchymal stem cells (MSCs) are found in all organs and play a critical role in repair and regeneration of tissue. We engineered bone marrow-derived MSCs and evaluated their response to ionizing radiation exposure. Epidermal growth factor receptor (EGFR) expression by certain types of cancers has been shown to induce radioresistance. In this study, we tested the feasibility of transfecting MSCs to overexpress EGFR (eMSC-EGFR) and their capacity to tolerate and recover from X-ray exposure. Quantitative real-time PCR (qRT-PCR) and immunoblotting results confirmed the efficient transfection of EGFR into MSCs and EGFR protein production. eMSC-EGFR maintained characteristics of human MSCs as outlined by the International Society for Cell & Gene Therapy. Then, engineered MSCs were exposed to various dose rates of X-ray (1–20 Gy) to assess the potential radioprotective role of EGFR overexpression in MSCs. Post-irradiation analysis included evaluation of morphology, cell proliferation, viability, tumorigenic potential, and DNA damage. eMSC-EGFR showed signs of radioresistance compared to naïve MSCs when assessing relative proliferation one week following exposure to 1–8 Gy X-rays, and significantly lower DNA damage content 24 h after exposure to 4 Gy. We establish for the first time the efficient generation of EGFR overexpressing MSCs as a model for enhancing the human body to tolerate and recover from moderate dose radiation injury in long-term manned space travel.

Interest in Current Good Manufacturing Practices (cGMP)-grade extracellular vesicles (EVs) is expanding. Some obstacles in this new but rapidly growing field include a lack of standardization and scalability. This review focuses on automated biomanufacturing of EVs in conditioned media collected from cultured mesenchymal stromal cells (MSCs). Different automated cell culture systems are discussed, including factors affecting EV quantity and quality, isolating EVs manufactured in an automated system, and validations needed. The ultimate goal when manufacturing cGMP-grade EVs is to identify a specific application and characterize the EV population in detail. This is achieved by validating every step of the process, choosing appropriate release criteria, and assuring batch-to-batch consistency. Due to the lack of standards in the field, it is critical to ensure that the cGMP-grade EVs meet FDA standards pertaining to identity, reproducibility, sterility, safety, purity, and potency. A closed-system automated bioreactor can be a valuable tool to generate cGMP-EVs in a scalable, economical, and reproducible manner.

Background: Despite numerous measures used to prevent pressure ulcers, their growing prevalence in recent years is expected to continue as the population ages. This review aims to report the outcomes of the regenerative potential of MSCs in treating pressure ulcers, assessing the effectiveness of MSCs in treating pressure ulcers. Methods: A computerized search for articles on animal models that use MSCs as primary therapy to treat pressure ulcers, published from conception to present, was conducted using PubMed, MEDLINE, Embase, and CINAHL. Our search yielded 52 articles, narrowed to 44 after excluding duplicates. Results: Out of 52 articles collected from four databases, 11 met the inclusion criteria. A total of 11 articles published between 2008 and 2020 met the inclusion criteria. Eight studies were observational descriptive papers in animal models, and three were prospective. Six studies used autologous MSCs, while five used allogenic MSCs. Three studies were conducted in humans, and the remaining eight were conducted in animals. The most common method of cell delivery was an intradermal injection in the margins of the ulcer. All studies reported positive results, including improved wound healing, reduced inflammation, and improved tissue regeneration. Conclusions: MSCs have shown promising results in treating pressure ulcers in animal and clinical trials. The combination of MSCs and scaffold materials has also been studied and found to be effective in wound healing. A standardized human wound model has been proposed further to investigate the efficacy of cell-based therapies for chronic wounds. However, more research is needed to determine the best quantity of cells to apply for pressure ulcers and to ensure the safety and efficacy of these treatments in clinical settings.

Background: The use of bone morphogenic protein and mesenchymal stem cells has shown promise in promoting bone regeneration in calvarial defects. However, a systematic review of the available literature is needed to evaluate the efficacy of this approach. Methods: We comprehensively searched electronic databases using MeSH terms related to skull defects, bone marrow mesenchymal stem cells, and bone morphogenic proteins. Eligible studies included animal studies that used BMP therapy and mesenchymal stem cells to promote bone regeneration in calvarial defects. Reviews, conference articles, book chapters, and non-English language studies were excluded. Two independent investigators conducted the search and data extraction. Results: Twenty-three studies published between 2010 and 2022 met our inclusion criteria after a full-text review of the forty-five records found in the search. Eight of the 23 studies used mice as models, while 15 used rats. The most common mesenchymal stem cell was bone marrow-derived, followed by adipose-derived. BMP-2 was the most popular. Stem cells were embedded in Scaffold (13), Transduction (7), and Transfection (3), and they were delivered BMP to cells. Each treatment used 2 × 104–1 × 107 mesenchymal stem cells, averaging 2.26 × 106. Most BMP-transduced MSC studies used lentivirus. Conclusions: This systematic review examined BMP and MSC synergy in biomaterial scaffolds or alone. BMP therapy and mesenchymal stem cells in calvarial defects, alone, or with a scaffold regenerated bone. This method treats skull defects in clinical trials. The best scaffold material, therapeutic dosage, administration method, and long-term side effects need further study.

Abstract Background We have previously shown bone marrow-derived mesenchymal stem cells (MSCs) may shift immune responses toward anti-inflammatory pathways and stabilize the course of obstructive chronic lung allograft syndrome (o-CLAD) after lung transplantation. In this study, we measured the response of lower dose infusions. Methods We infused low-dose MSCs intravenously in 13 patients who had developed moderate-to-severe o-CLAD. Three had previously received an infusion of MSCs from a different donor and were re-dosed at 1 × 106 MSC/kg, while 5 received a first dose at 1 × 106 MSC/kg and five received an even lower dose at 0.5 × 106 MSC/kg. We recorded pulmonary function tests before and after infusion, and patients were followed clinically for 12 months. Results Infusions were well tolerated, and no significant adverse events were recorded in the first 30 days. There was significant decline (mean ± SD) in forced vital capacity (FVC) (3.49 ± 1.03 vs 3.18 ± 0.94 L, P = .03) and forced expiratory volume in 1 second (FEV1) (2.28 ± 0.86 vs 1.77 ± 0.49 L, P = .04) over the year preceding infusion. FVC (3.18 ± 0.94 vs 3.46 ± 0.99 L, P = .53) and FEV1 was not significantly changed (1.77 ± 0.49 vs 1.88 ± 0.75, P = .72) when comparing values immediately prior to infusion to those obtained 1 year after infusion, indicating a possible stabilizing effect on lung function decline due to o-CLAD. Conclusion Intravenous infusions of bone marrow-derived MSCs are well tolerated in lung transplant recipients with moderate-to-severe CLAD. Low-dose MSCs appear to slow progression of CLAD in some patients.

AbstractBackgroundChimeric 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 designWe 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.ResultsApheresis 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).ConclusionsApheresis 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.

Mesenchymal stem cells (MSCs) are used in various studies to induce immunomodulatory effects in clinical conditions associated with immune dysregulation such as graft versus host disease (GvHD). However, most of these clinical trials failed to go beyond early phase 2 studies because of limited efficacy. Various methods have been assessed to increase the potency of MSCs. IL-10 is an anti-inflammatory cytokine that is known to modulate immune responses in GvHD. In this study, we evaluated the feasibility of transfecting IL-10 mRNA to enhance MSC therapeutic potential. IL-10 mRNA engineered MSCs (eMSCs-IL10) maintained high levels of IL-10 expression even after freezing and thawing. IL-10 mRNA transfection did not appear to alter MSC intrinsic characteristics. eMSCs-IL10 significantly suppressed T cell proliferation relative to naïve MSCs in vitro. In a mouse model for GvHD, eMSCs-IL10 induced a decrease in plasma level of potent pro-inflammatory cytokines and inhibited CD4+ and CD8+ T cell proliferation in the spleen. In summary, our studies demonstrate the feasibility of potentiating MSCs to enhance their immunomodulatory effects by IL-10 mRNA transfection. The use of non-viral transfection may generate a safe and potent MSC product for treatment of clinical conditions associated with immune dysregulation such as GvHD.

Blood plasma is a readily accessible source of extracellular vesicles (EVs), i.e., cell-secreted nanosized carriers that contain various biomolecules, including glycans. Previous studies have demonstrated that glycans play a major role in physiological and pathological processes, and certain plasma glycans have been associated with disease conditions. However, glycome studies have been limited by a lack of analytical techniques with the throughput capacity necessary to study hundreds of clinical samples. This study is the first to characterize the EV plasma glycome based on all major glycan classes. The results based on glycan node analysis revealed, as expected, that plasma-derived EVs have distinct glycan features from donor-matched whole plasma. Specifically, glycan nodes corresponding to those observed in chondroitin sulfate, dermatan sulfate, type I keratan sulfate, and type II keratan sulfate were enriched on EVs. The identification of specific differences in glycan features in plasma vs. plasma-derived EVs is relevant for understanding the physiological role of EVs and as a reference for future diagnostic studies. Additionally, the results indicate that EV glycan nodes do not substantially differ among a small set of healthy donors. These results lay the framework for the further evaluation of all EV glycan classes as diagnostic markers, therapeutic targets, and biologically active components in health and disease.