Blood components for topical use in tissue regeneration: evaluation of corneal lesions treated with platelet lysate and considerations on repair mechanisms.
BACKGROUND
The fields of application of topically administered platelet derivatives are numerous and increasing. The use of this blood component is based on the fact that it contains growth factors and proteins of the clotting system. Studies carried out so far have been aimed at identifying these substances, assaying their content in the various types of platelet concentrate used, determining the in vivo and in vitro mechanisms of action, and trying to standardise the production methods. However, much still remains to be discovered, not only about the growth factors, but also about all those cytokines and biochemical mediators that are involved in the processes of tissue regeneration.


METHODS
We studied the use of platelet lysate, obtained from platelet-rich plasma which had been frozen, for the treatment of corneal ulcers caused by neurotrophic keratitis and of epithelial and stromal loss following physical or chemical trauma. The platelet lysate was administered in the form of eye drops to patients who had not responded to conventional therapy and who were at risk of corneal scarring.


RESULTS
The results were satisfactory in terms of both tissue regeneration and healing time. The clinical follow-up showed a clear reduction in the time of regeneration of the damaged epithelium and stabilisation of the repair process. The epithelial defects disappeared completely in all the treated eyes within 6 to 32 days, with the time depending on the type of lesion and the severity of the damage.


CONCLUSIONS
The cornea reacts to damage by releasing numerous substances, including cytokines, growth factors, proteases and neuropeptides in order to restore its anatomical integrity. A change in the balance between inhibitory and stimulating substances can lead to the development of complications. Fast, correct re-epithelialisation is fundamental for the formation of new, transparent tissue. The use of non-gelified platelet-rich plasma was found to be effective in all cases with loss of epithelium, such as post-herpetic corneal ulcers or ulcers occurring following trauma or exposure to caustic substances.
Geremicca
Walter
W
SIMTI ASP., Crotone, Italy. wgsit.crotone@libero.it
Fonte
Carla
C
Vecchio
Sisto
S
D000287:Administration, Topical; D000328:Adult; D000368:Aged; D001792:Blood Platelets; D002457:Cell Extracts / Q000008:administration & dosage / Q000494:pharmacology / Q000627:therapeutic use*; D003315:Cornea / Q000502:physiology; D003320:Corneal Ulcer / Q000503:physiopathology / Q000628:therapy*; D019573:Epithelium, Corneal / Q000187:drug effects / Q000473:pathology; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D007322:Instillation, Drug; D008297:Male; D018613:Microscopy, Confocal; D008875:Middle Aged; D009883:Ophthalmic Solutions; D012038:Regeneration / Q000187:drug effects*; D012189:Retrospective Studies
D002457:Cell Extracts; D009883:Ophthalmic Solutions
Clin Orthop Relat Res. 1991 Feb;(263):30-48
1993386
Transfusion. 2004 Dec;44(12):1724-31
15584987
Blood. 1979 Jun;53(6):1043-52
444648
Oral Surg Oral Med Oral Pathol Oral Radiol Endod. 1998 Jun;85(6):638-46
9638695
Thromb Haemost. 1997 Jul;78(1):661-6
9198235
Ophthalmology. 1996 Apr;103(4):590-4
8618757
Lancet. 1997 Feb 1;349(9048):334
9045025
Transfusion. 2004 Jul;44(7):1013-8
15225241
Blood Rev. 1989 Dec;3(4):269-76
2692747
Bone. 2004 Apr;34(4):665-71
15050897
Lancet. 1992 Jan 4;339(8784):23-5
1345953
J Vasc Surg. 2004 May;39(5):1146-7; author reply 1147
15134090
Am J Surg. 2001 Aug;182(2 Suppl):21S-28S
11566473
Biomaterials. 2003 Jun;24(14):2497-502
12695076
Implant Dent. 2004 Mar;13(1):73-8
15017308
Cell Transplant. 2003;12(5):509-18
12953925
Biomaterials. 2004 Aug;25(18):4489-502
15046940
Vox Sang. 2001 Oct;81(3):172-5
11703860
J Orthop Res. 1995 Sep;13(5):655-63
7472743
Transfusion. 2005 Nov;45(11):1759-67
16271101
Transfusion. 2001 Oct;41(10):1217-24
11606819
Clin Exp Ophthalmol. 2004 Oct;32(5):472-7
15498057
Am J Surg. 2001 Aug;182(2 Suppl):1S-7S
11566470
J Oral Maxillofac Surg. 1997 Nov;55(11):1294-9
9371122
Am J Ophthalmol. 2003 Jul;136(1):197-9
12834697
Thromb Haemost. 2001 Jan;85(1):142-51
11204566
J Clin Endocrinol Metab. 1992 Jul;75(1):1-4
1618994
Transfusion. 1999 Feb;39(2):144-8
10037123
N Engl J Med. 1999 Sep 2;341(10):738-46
10471461
J Vasc Surg. 2003 Dec;38(6):1342-8
14681639
J Periodontol. 1996 May;67(5):545-53
8724716
J Craniomaxillofac Surg. 2002 Apr;30(2):97-102
12069512
Vox Sang. 2008 Apr;94(3):202-208
18179680
Proc Natl Acad Sci U S A. 1997 Sep 30;94(20):10669-74
9380693
Dig Surg. 2000;17(1):77-80
10720836
Vox Sang. 2003 Nov;85(4):283-9
14633254
Int J Artif Organs. 2004 Sep;27(9):816-7
15521224
Haemostasis. 2001 Mar-Apr;31(2):71-9
11684862
Int J Periodontics Restorative Dent. 2002 Feb;22(1):45-53
11922217
Curr Urol Rep. 2001 Feb;2(1):79-82
12084299
J Long Term Eff Med Implants. 1998;8(2):161-73
10181374
Fed Proc. 1983 Jun;42(9):2630-4
6303866
Transfus Apher Sci. 2004 Apr;30(2):145-51
15062754
Annu Rev Med. 1987;38:71-9
3555311
Transfusion. 2001 Oct;41(10):1186-9
11606813
Int Endod J. 2004 Feb;37(2):145-50
14871182
J Oral Implantol. 2005;31(1):2-17
15751383
Ann Periodontol. 2003 Dec;8(1):193-204
14971254
Laryngoscope. 2001 Apr;111(4 Pt 1):642-4
11359133
Facial Plast Surg. 2002 Feb;18(1):27-33
11823930