Dr. Trostle attended the NAVRMA meeting in Lexington and has brought back some of the clinical highlights.
How do stem cells work: The original thoughts focused on stem cells "regenerating" damaged cells, tissue and arguably even complete organs? The regeneration of cells is possible, but tissue and organs seems to be much less likely at this time. It is now thought that stem cells have an equal or more important role in cell messenger/signaling.
Joints - From Dr. Nixon's lab at Cornell. Stem cells do not home to cartilage injury in normal or osteoarthritic joints. Intra-articular (IA) injections of stem cells are not a useful technique for cartilage resurfacing. However IA stem cells were found in large numbers in the synovial tissues and it appears they modify synovial fluid constitutes, inflammation and cytokine profiles. Some clinical cases have developed joint flare following stem cell injections. The cause of the stem cell joint flares is unknown. The possibilities include dead stem cells, the solution stem cells are suspended in, and the environment in which the cells are being placed.
Fat vs. Bone Marrow vs. Umbilical Cord: Stem cells can be derived from all tissues, some more easily than others. A lot of debate still exists if any one source is better. Fat derived stem cells can be obtained quickly because the tissue sample is basically denatured and cells are left over. Total number of true stem cells is only 2-4% in a fat sample. There are a large number of other nucleated cells often referred to as the stromal fraction. Bone marrow and umbilical cord derived stem cells are all cultured in a lab and undergo expansion to achieve a much larger number of stem cells. It appears that all stem cells can be cyropreserved with little problem or adversity to viability.
Delivery: Most stem cells have been injected directly into soft tissue lesions using U/S guidance. There were studies in which stem cells have been labeled or marked and able to document homing of stem cells delivered via intravenous regional limb perfusion (IV-RLP) to inflamed areas. IV-RLP delivery of stem cells to extremities in becoming more common as it is technically less difficult to do, and provides treatment to multiple areas.
Dose: There have been no good studies to date to suggest what the appropriate dose of stem cells are for effective therapy. A common dose has been between 10-20 million stem cells. There was a high degree of variability reported in stem cell life span, anywhere from 3-4 days up to 160 days. There are some anecdotal reports that higher/mega doses (50,000 -100,000) have an improved treatment outcome. Others are taking a different approach and recommending that stem cell dose frequency increase in lieu of their potentially short viability.