Search Results (4)

Cellular transplantation therapies have been extensively used in experimental spinal cord injury research. However, there is no consensus as to what the most effective cellular controls for the therapeutic cell of interest are. For this reason, we examined whether dead cells obtained through prolonged heat treatment can act as an appropriate cellular control for intravenously injected Sca-1+ mesenchymal precursor cells (MPCs) in C5 unilateral contusion cervical spinal cord injury. This was tested in single intravenous MPC injection alone or intravenous MPC plus intraspinal neural stem cell (NSC) combinatory transplantation studies. MPCs were isolated from the compact bone of FVB mice, while NSCs were isolated from the subventricular zone of luciferase–GFP transgenic FVB mice. Dead MPCs were obtained by heating at 72 °C for at least 12 h. In the MPC only transplant study, injured mice received an injection of 1 × 10⁶ dead or live MPCs D1 post-injury. Mice were then sacrificed at 8 weeks post-injury. In this study, intravenous injections of dead MPCs showed no statistical difference in injured paw usage compared to live MPCs, but behavior was improved compared to the media-vehicle-only control at D7 and D21. In the combinatory MPC plus NSC transplant study, injured mice received an intravenous injection of 1 × 10⁶ dead or live MPCs D1 post-injury followed by intraspinal injection of 100,000 NSCs at D3 or D7 post-injury. Another two cohorts of mice received only NSCs at D3 or D7 post-injury. Mice were then sacrificed at 6 weeks post-injury. In this study, there was no functional difference in any of the groups in the dual injection study. Morphologically, mice receiving IV injection of dead MPCs had a smaller lesion size compared to the vehicular control, but the lesion size was larger than that of the lesion size in mice receiving live MPC injection. Dead cells elicited functional and anatomical benefits for the spinal-cord-injured mice. In summary, dead cells obtained through prolonged heat treatment proved to be inconsistent and not optimal for use as cellular controls for cell transplantation studies in spinal cord injury but provide positive evidence for non-transplantation-based cell therapies. Full article

Mesenchymal progenitor cells (MPC) are effective in reducing tissue loss, preserving white matter, and improving forelimb function after a spinal cord injury (SCI). We proposed that by preconditioning the mouse by the intravenous delivery (IV) of MPCs for 24 h following SCI, this would provide a more favorable tissue milieu for an NSC intraspinal bridging transplantation at day three and day seven. In combination, these transplants will provide better anatomical and functional outcomes. The intravenous MSCs would provide cell protection and reduce inflammation. NSCs would provide a tissue bridge for axonal regeneration and myelination and reconnect long tract spinal pathways. Results showed that initial protection of the injury site by IV MPCs transplantation resulted in no increased survival of the NSCs transplanted at day seven. However, integration of transplanted NSCs was increased at the day three timepoint, indicating MPCs influence very early immune signaling. We show, in this study, that MPC transplantation resulted in a co-operative NSC cell survival improvement on day three post-SCI. In addition to increased NSC survival on day three, there was an increase in NSC-derived mature oligodendrocytes at this early timepoint. An in vitro analysis confirmed MPC-driven oligodendrocyte differentiation, which was statistically increased when compared to control NSC-only cultures. These observations provide important information about the combination, delivery, and timing of two cellular therapies in treating SCI. This study provides important new data on understanding the MPC inflammatory signaling within the host tissue and timepoints for cellular transplantation survival and oligodendroglia differentiation. These results demonstrate that MPC transplantation can alter the therapeutic window for intraspinal transplantation by controlling both the circulating inflammatory response and local tissue milieu. Full article

Colorectal cancer (CRC) is one of the most frequent and deadly forms of cancer. About half of patients are affected by metastasis, with the cancer spreading to e.g., liver, lungs or the peritoneum. The majority of these patients cannot be cured despite steady advances in treatment options. Immunotherapies are currently not widely applicable for this disease, yet show potential in preclinical models and clinical translation. The tumour microenvironment (TME) has emerged as a key factor in CRC metastasis, including by means of immune evasion—forming a major barrier to effective immuno-oncology. Several approaches are in development that aim to overcome the immunosuppressive environment and boost anti-tumour immunity. Among them are vaccination strategies, cellular transplantation therapies, and targeted treatments. Given the complexity of the system, we argue for rational design of combinatorial therapies and consider the implications of precision medicine in this context. Full article

Electric fields have been studied extensively in biomedical engineering (BME) for numerous regenerative therapies. Recent studies have begun to examine the biological effects of electric fields in combination with other environmental cues, such as tissue-engineered extracellular matrices (ECM), chemical gradient profiles, and time-dependent temperature gradients. In the nervous system, cell migration driven by electrical fields, or galvanotaxis, has been most recently studied in transcranial direct stimulation (TCDS), spinal cord repair and tumor treating fields (TTF). The cell migratory response to galvano-combinatory fields, such as magnetic fields, chemical gradients, or heat shock, has only recently been explored. In the visual system, restoration of vision via cellular replacement therapies has been limited by low numbers of motile cells post-transplantation. Here, the combinatory application of electrical fields with other stimuli to direct cells within transplantable biomaterials and/or host tissues has been understudied. In this work, we developed the Gal-MµS device, a novel microfluidics device capable of examining cell migratory behavior in response to single and combinatory stimuli of electrical and chemical fields. The formation of steady-state, chemical concentration gradients and electrical fields within the Gal-MµS were modeled computationally and verified experimentally within devices fabricated via soft lithography. Further, we utilized real-time imaging within the device to capture cell trajectories in response to electric fields and chemical gradients, individually, as well as in combinatory fields of both. Our data demonstrated that neural cells migrated longer distances and with higher velocities in response to combined galvanic and chemical stimuli than to either field individually, implicating cooperative behavior. These results reveal a biological response to galvano-chemotactic fields that is only partially understood, as well as point towards novel migration-targeted treatments to improve cell-based regenerative therapies. Full article