The Biological Fitness of Bone Progenitor Cells in Reamer/Irrigator/Aspirator Waste

Abstract

Background The biological waste collected during the Reamer-Irrigator-Aspirator (RIA) procedure has 5 been described as an abundant source of bone progenitor cells with a comparable osteogenic gene profile to donor-matched iliac crest-bone marrow (IC-BM). However, it is not clear if these RIA-waste (RIA-W) cells are biologically fit. We aimed to evaluate the stress levels and functions of RIA-W progenitor cells. 9 Methods The Reactive Oxygen Species (ROS) levels were tested in freshly-collected bone progenitor 11 cells (defined as CD45 low CD271 high cells) using flow-cytometry. Induced ROS levels in these cells were measured under hypoxia and/or oxidative stress as well as under experimental 13 simulation of RIA procedure. Furthermore, the alkaline phosphatase (ALP) expression 14 levels, proliferation and senescence of culture-expanded RIA-W and IC-BM Mesenchymal 15 Stromal Cells (MSCs) were compared. 16 Results RIA-W and donor-matched IC-BM CD45 low CD271 high cells were 97% and 98% viable, but the ROS levels for RIA-W cells were significantly higher than IC-BM cells (p=0.0020). Also, hypoxia-, oxidative stress-or both-induced ROS were higher for RIA-W cells (p=0.0312, p=0.0078, and p=0.0312 respectively). The dilution with saline, suction pressure, and irrigation-effect reduced cell viability with a positive correlation of the ROS levels (p=0.0035). The RIA-W and IC-BM colony-forming cells (average 96,100 and 11,000, respectively) showed comparable ALP levels. Furthermore, culture-expanded RIA-W and IC-BM MSCs showed comparable ROS, ALP levels, death susceptibility and proliferation. 25 Conclusions Although freshly-collected RIA-W bone progenitor cells seemed to be transiently stressed, these cells were as viable, but higher in numbers than IC-BM cells. The proliferation and osteogenesis of both cells were comparable. Clinical Relevance The RIA-W bag should not be wasted as containing bone progenitor cells with promising 31 potential for regenerative application.

Factors Influencing the Yield of Progenitor Cells in Bone Marrow Aspiration Concentrate—A Retrospective Analysis of 58 Patients

“…Tanikawa et al reported no significant differences between MNC counts derived from bone marrow needles, either with side holes or without side holes [ 32 ]. Apart from the iliac crest aspirates, the residue of reamer irritator aspirate was also shown to possess similar proliferative potential [ 33 ].…”

Safety and efficacy of a novel retrograde route for femoral bone graft harvesting by Reamer-Irrigator-Aspirator: a pilot study on 24 patients

“…El-Jawhari et al evaluated the biological fitness of bone progenitor cells in RIA waste. The authors found that the RIA-W bag, which is generally wasted in routine practice may offer great clinical value as an abundant source of functionally competent bone progenitor cells [ 14 ].…”

Quantitative Analysis of Growth Factors From Cancellous Bone Graft Collected With a Reamer-Irrigator-Aspirator System From Native Long Bones Versus Previously Reamed Long Bones

“…In addition to the presence of growth factors, previous studies have concluded that the presence of viable progenitor cells is critical to the true osteogenic potential of RIA-harvested cancellous bone graft. 13,[15][16][17] Future studies assessing the presence and function of progenitor cells in NR and RRR cancellous bone grafts are warranted to more fully evaluate the osteogenic potential.…”