Leukocyte-Rich Platelet-Rich Plasma Injections Do Not Up-Modulate Intra-Articular Pro-Inflammatory Cytokines in the Osteoarthritic Knee.
BACKGROUND
The presence of leukocytes in platelet concentrates is deemed to cause deleterious effects when injected intra articularly. The aim of this study is to analyse both local and systemic effects induced by leukocyte-rich Platelet-rich Plasma (PRP) injections through a proteomic characterization of serial synovial fluid and blood samples obtained from subjects treated for knee OA. Secondary aim was to compare the effects on knee homeostasis and systemic response with those obtained with visco-supplementation.


METHODS
Thirty-six OA patients treated either by autologous L-PRP or HA intra-articular knee injections, administered in series of three at one-week intervals, were analyzed. Just before the injection, 1 ml of synovial fluid was collected through the same needle way. In the same time, a peripheral blood sample was obtained and plasma separated. A further peripheral blood sample was collected at 2, 6, and 12 months. L-PRP, plasma and synovial fluid were tested by multiplex bead-based sandwich immunoassay by means of the Bio-Plex suspension array system (Bio-Rad Laboratories) for the presence of pro- and anti-inflammatory cytokines (IL-1beta, IL-6, IL-8, IL-17 and IL-4, IL-10, IL-13) and growth factors (FGF-b, HGF, PDGF-AB/BB).


RESULTS
In general, pro-inflammatory cytokine levels were similar at basal condition and after treatment whereas anti-inflammatory ones were nearly undetectable. L-PRP administration did not modulate significant changes of cytokine concentrations either in synovial fluid or plasma, whatever the time points analyzed. No different trend was observed between L-PRP and HA administration in terms of pro- and anti-inflammatory cytokines, as well as growth factors.


CONCLUSIONS
In contrast with the evidence reported by "in vitro" studies, where a cellular pro-inflammatory response appears to be induced by the presence of leukocytes, these results suggest that the presence leukocyte-rich PRP doesn't induce a relevant in vivo up regulation of pro-inflammatory mediators.
Laboratory of Immunorheumatology and Tissue Regeneration/RAMSES, Rizzoli Orthopaedic Institute, Bologna, Italy.|Department of Medical and Surgical Sciences, University of Bologna, Bologna, Italy.
Erminia
E
Mariani
Laboratory of Immunorheumatology and Tissue Regeneration/RAMSES, Rizzoli Orthopaedic Institute, Bologna, Italy.
Valentina
V
Canella
Laboratory of Immunorheumatology and Tissue Regeneration/RAMSES, Rizzoli Orthopaedic Institute, Bologna, Italy.
Luca
L
Cattini
Laboratory of Biomechanics and Technology Innovation/NABI, 2nd Orthopaedic and Traumatologic Clinic, Rizzoli Orthopaedic Institute, Bologna, Italy.
Elizaveta
E
Kon
Laboratory of Biomechanics and Technology Innovation/NABI, 2nd Orthopaedic and Traumatologic Clinic, Rizzoli Orthopaedic Institute, Bologna, Italy.
Maurilio
M
Marcacci
Laboratory of Biomechanics and Technology Innovation/NABI, 2nd Orthopaedic and Traumatologic Clinic, Rizzoli Orthopaedic Institute, Bologna, Italy.
Berardo
B
Di Matteo
Laboratory of Immunorheumatology and Tissue Regeneration/RAMSES, Rizzoli Orthopaedic Institute, Bologna, Italy.
Lia
L
Pulsatelli
Laboratory of Biomechanics and Technology Innovation/NABI, 2nd Orthopaedic and Traumatologic Clinic, Rizzoli Orthopaedic Institute, Bologna, Italy.
Giuseppe
G
Filardo
D000368:Aged; D016207:Cytokines / Q000378:metabolism*; D005260:Female; D006801:Humans; D007249:Inflammation / Q000378:metabolism / Q000628:therapy*; D007719:Knee Joint / Q000378:metabolism*; D007962:Leukocytes / Q000378:metabolism*; D008297:Male; D008875:Middle Aged; D020370:Osteoarthritis, Knee / Q000378:metabolism / Q000628:therapy*; D053657:Platelet-Rich Plasma; D013582:Synovial Fluid / Q000378:metabolism; D016896:Treatment Outcome
D016207:Cytokines