Immunoglobulin G in Platelet-Derived Wound Healing Factors

Abstract

We intended to reformulate an existing platelet-derived wound healing formula to target each phase of the healing wound with the appropriate phase-specific molecules. A decreased perfusion of the skin, often associated with conditions such as thalassemia, sickle cell disease, diabetes mellitus, and chronic vascular disease, is the most common etiology of cutaneous ulcers and chronic wounds. We had previously shown that a PDWHF topically applied to a chronic nonhealing ulcer of a β-thalassemia homozygote stimulated and accelerated closure of the wound. The PDWHF was prepared from a pooled platelet concentrate of a matching blood group, consisting of a combination of platelet α-granule-derived factors. Processing of the apheresis-pooled platelets yielded various amounts of proteins ( 3.36 g / mL ± 0.25 (SD) ( N = 10 )) by the better lysis buffer method. Immunoglobulin G was found to be the most abundant α-granule-secreted protein. Equally broad quantities of the IgG ( 10.76 ± 12.66 % (SD) ( N = 10 )) and IgG/albumin ratios ( 0.6 ± 0.4 (SD) ( N = 10 )) were quantified. We have developed a method using a reformulated lysis buffer followed by size exclusion chromatography and affinity chromatography to extract, identify, quantify, and purify IgG from activated platelets. IgG purification was confirmed by Western blot and flow cytometry. It was thought unlikely that the platelet IgG could be accounted for by adsorption of plasma protein, though the variable quantities could account for diversity in wound healing rates. The IgG could protect the wound even from subclinical infections and functionally advance healing. It may be useful in the management of skin ulcers in the early phase of wound healing.

A comparative profile of total protein and six angiogenically-active growth factors in three platelet products

“…While both protein recovery and GF composition varied considerably among the explored PDPs, we demonstrate that all are an abundant source of EGF, VEGF, HGF, SDF-1α, endostatin, and TGF-β1. The data complimented previous work from this laboratory that uncovered substantial amounts of IgG and albumin in the PDPs [ 22 ]. It can thus be summarized that, collectively, these molecules protect wounds from even subclinical infection and inflammation, while promoting angiogenesis and healing.…”

“…All supernatant (plasma) was discarded, and the pellet vigorously shaken with 20 mL of lysis buffer (0.9% sodium chloride, 0.3% ammonium chloride and 0.3% sodium dihydrogen phosphate; Sigma-Aldrich, Munich, Germany), modified by Seria et al [ 22 ].…”

“…Platelet-derived products (PDPs) have emerged as strong contenders, with several studies demonstrating their effectiveness for CWs and dental and musculoskeletal events [ 9 ], [ 10 ], [ 11 ], [ 12 ], [ 13 ], [ 14 ], [ 15 ], [ 16 ], [ 17 ]. The effect is due to platelets’ wealth of bioactive molecules, chiefly released from their alpha granules such as immunoglobulins and growth factors (GFs) capable of modulating each stage of wound healing [ 9 ], [ 10 ], [ 11 ], [ 12 ], [ 13 ], [ 14 ], [ 15 ], [ 16 ], [ 17 ], [ 18 ], [ 19 ], [ 20 ], [ 21 ], [ 22 ], [ 23 ]. PDPs may therefore be applied to wounds, to stave off and quell infection (IgG content), and simultaneously promote tissue healing through the physiological release of GFs.…”