Evaluation of Platelet-Rich Plasma and Neutrophil Antimicrobial Extract as Two Autologous Blood-Derived Agents

Abstract

The platelet-rich plasma (PRP) and antimicrobial peptides neutrophil extract (AMP extract) were prepared from rabbit neutrophils as two autologous blood-derived preparations, which could be applied locally to enhance healing process of tissues. Both preparations were analyzed using the MALDI TOF method for accurate qualitative assay. Growth factors (PDGF and VEGF) and microbicidal protein were reported in PRP. In AMP extract a-defensins, namely; NP-1, -2, -3a, -3b, -4, and -5 and cathelicidins represented among other by 15-kDa antibacterial protein (p15s) were detected. In the second part of our study the influence of antimicrobial extract on macrophages in vitro was tested. Then, degranulation of neutrophils in vitro and generation of reactive intermediates by these cells under the influence of AMP extract were assessed. As estimated, the addition of AMP extract into cultures of macrophages decreased superoxide anion generation after 5 days of incubation. Furthermore, AMP extract inhibited degranulation and respiratory burst in neutrophils, therefore in this regard it suppress proinflammatory effect of two studied populations of leukocytes.

The Neutrophil Response to Rabbit Antimicrobial Extract After Implantation of Biomaterial into a Bone/Cartilage Defect

“…For this experiment, a crude neutrophil extract and its two fractions [high molecular mass fraction 1 (F1) and low molecular mass fraction 2 (F2)] were used. As determined in our previous work (11), F1 of the neutrophil extract consisted of rabbit cathelicidins of higher molecular masses, namely 15 kDa AMP (a mass of 15,626 Da), cathelin-like fragments of about 11,000 Da, and products of fragmentation of rabbit cathelicidin CAP 18. In contrast, in F2 of low molecular masses, defensins from rabbit neutrophils, namely NP-1, NP-2, NP-3a, NP-3b, NP-4 and NP-5, were detected.…”

Application of Platelet-rich Plasma and Tricalcium Phosphate in the Treatment of Comminuted Fractures in Animals

“…The biomaterial used was TCP in the form of granules, 150-500 μm in diameter, whose structure corresponded to that of cancellous bone (2), with the addition of activated autologous PRP as the binding agent, facilitating implantation at the site of the fracture and acting as a source of growth factors. The method of obtaining the gel and its exact content have been discussed in our previously published study (19).…”

Changes in the activity of ovine blood-derived macrophages stimulated with antimicrobial peptide extract (AMP) or platelet-rich plasma (PRP)

“…Superoxide production was measured using a method given previously (24). In brief, the media obtained from cultures of Mfs with different stimulators were incubated with 0.1% nitroblue tetrazolium (Sigma-Aldrich, Poland) solution at room temperature for 15 min and then absorbance was read.…”

“…Some mixtures of natural preparations based on antimicrobial peptides have been evaluated as therapeutic means for fighting infections and strengthening host defence mechanisms (2). As noted previously, a rabbit AMP extract was evaluated which consisted of a 15 kDa antimicrobial peptide, cathelin-like fragments, CAP 18, and rabbit defensins NP-1, NP-2, NP-3a, NP-3b, NP-4, and NP-5, and may be regarded as a promising new therapeutic approach for regulation of the intensity of the inflammatory process with the potential for immunomodulation (24).…”