Our laboratory studies the interaction of the immune and central nervous systems after spinal cord injury (SCI). Differences in the immune systems of rodents and humans represent a critical barrier to translating promising immune modulatory therapies to SCI patients. Therefore, my focus has been to establish humanized mice (i.e. mice with human immune systems) to study human immune responses within a controlled experimental SCI paradigm. Our initial studies have shown that human immune cells infiltrate the injured spinal cord, increase lesion size, and impair functional recovery. Future studies will continue to develop this model for investigating human immune function after SCI, particularly in the context of hematopoiesis, immune suppression, and graft rejection.
I am also interested in understanding the how SCI alters hematopoiesis, the process of generating immune and red blood cells from hematopoietic stem & progenitor cells (HSPCs) within the bone marrow environment. Clinical data suggests that the proliferation, apoptosis, and functional potential of HSPCs are altered after SCI. Therefore, we believe that SCI impairs the ability of HSPCs to generate functional immune and red blood cells, which may contribute to anemia and systemic immune suppression, both of which can occur in SCI patients. Current experiments hope to characterize the hematopoietic response to SCI and determine underlying molecular and cellular mechanisms. Data from these studies will help identify novel therapeutics to improve immune function and prevent morbidity and mortality from infectious complications.
2017 - NIH F31 NRSA Fellowship
Carpenter RS, Iwuchukwu I, Hinkson CL, Reitz S, Lee W, Kukino A, Zhang A, Pike MM, Ardelt AA. (2016) High-dose estrogen treatment at reperfusion reduces lesion volume and accelerates recovery of sensorimotor function after experimental ischemic stroke. Brain Research; 1639:200-213.
Carpenter RS, Kigerl KA, Marbourg JM, Gaudet AD, Huey D, Niewiesk S, Popovich PG. (2015) Traumatic spinal cord injury in mice with human immune systems. Experimental Neurology 17;271:432-444.
IGP Symposium; Med Center Research Day; Keystone Symposium – Hematopoiesis (2/2017)
Randall S. Carpenter, Phillip G. Popovich. High-thoracic spinal cord injury alters the activity and function of hematopoietic stem & progenitor cells. OSUWMC Trainee Research Day & Life Sciences IGP Symposium (2016 – poster), Columbus, OH
Randall S. Carpenter, Kristina A. Kigerl, Devra Huey, Stefan Niewiesk, Phillip G. Popovich. Human immune cells infiltrate the lesion of humanized mice after contusive spinal cord injury. Life Sciences IGP Symposium (2015 - poster), Columbus, OH.