Factors Influencing Outcomes in Cultivated Limbal Epithelial Transplantation for Chronic Cicatricial Ocular Surface Disorders

Abstract

Cultivated limbal epithelial transplantation (CLET) is a recently developedsurgical method to reconstruct the ocular surface in eyes with limbal dysfunction. The concept of the CLET is to produce a limbal epithelial sheet containing progenitor cells of the corneal epithelium, and then to transplant to the ocular surface following excision of cicatricial tissues. The method was first reported by Pellegrini et al in 1997, followed by several other investigators including our group. [1][2][3][4][5][6][7][8][9][10][11][12] In our previous report in 2002, the short-term outcomes of CLET were comparable with conventional limbal epithelial transplantation. 7 We found that the method did not produce excellent outcomes in patients with severe cicatricial ocular surface disorders such as Stevens-Johnson syndrome (SJS) and chemical/thermal burns of the cornea. 7 This may be due to the fact that many of the patients had risk factors for poor epithelialization such as decreased tear production, lid abnormalities, persistent inflammation. [13][14][15] It is not clear whether the relatively poor outcomes of our previous report can be improved by the modification of the epithelial sheet preparation. There are a variety of factors that may influence the quality of the epithelial sheet, which include; source of cells, preparation of the cells, types of substrates used, cultivation medium, the use of feeder cells, and culture conditions. Our group has made some modification of the cultivation/preparation methods including the use of feeder cells, cell suspension technique and air-lifting of the cell sheet.In order to investigate whether the modification resulted in improvement in surgical outcomes, we retrospectively studied the mid-term outcomes of CLET. The mid-term outcomes of CLET for chronic cicatricial ocular surface disorders were compared with the different cultivation methods. Also, other factors were analyzed to see if they influenced the results. METHODS PatientsTwenty nine eyes of 27 patients that had CLET between June 1999 and November 2003 were retrospectively analyzed in this study. Patients consisted of 16 males and 11 females, with a mean age of 50.2 + 20.7 years (15-82 years). All eyes had total limbal dysfunction. Conjunctivalization was confirmed preoperatively by impression cytology in 10 of 27 eyes. Mean corrected visual acuity was counting fingers, and two-third of the eyes had less than 20/2000. Schirmer`s test was performed in 21 eyes and decreased tear secretion (Schirmer`s value < 5 mm) was noted in 12 eyes. As for preoperative complications, glaucoma, macular degeneration, and lid deformity were noted in 4, 1, and 3 eyes, respectively.

13 years of cultured limbal epithelial cell therapy: A review of the outcomes

“…This review includes 28 case reports and series published over the past 13 years [Pellegrini et al, 1997;Schwab, 1999;Schwab et al, 2000;Tsai et al, 2000;Rama et al, 2001Rama et al, , 2010Koizumi et al, 2001a,b;Grueterich et al, 2002;Nakamura et al, 2003Nakamura et al, , 2004Nakamura et al, , 2006Sangwan et al, 2003Sangwan et al, , 2005Daya et al, 2005;Ang et al, 2007;Fatima et al, 2007;Kawashima et al, 2007;Shimazaki et al, 2007;Shortt et al, 2008;Di Girolamo et al, 2009;Meller et al, 2009;Baradaran-Rafii et al, 2010;Colabelli Gisoldi et al, 2010;Di Iorio et al, 2010;Kolli et al, 2010;Pauklin et al, 2010]. There were 10 studies with 5 patients or less, 13 studies with 6-20 patients, and 5 with more than 20 patients.…”

“…Some groups used animal-free culture and/or good manufacturing practice conditions. The suspension method of cultures was used in 12 studies and the explant one in 18, with 2 of the studies employing both methods [Nakamura et al, 2006;Shimazaki et al, 2007].…”

Concise Review: The Coming of Age of Stem Cell Treatment for Corneal Surface Damage

“…Decreased tear secretion, squamous metaplasia of conjunctival epithelium, and lid margin keratinization adversely affect the outcome of limbal epithelial transplantation [26]. In these patients, the chances of performing autograft transplantation is minimal when compared with unilateral LSCD caused by chemical or thermal burns because the disease affects the quality of cells in both eyes.…”

Concise Review: Hurdles in a Successful Example of Limbal Stem Cell-based Regenerative Medicine

“…Those media might have induced stimulation of different cellular pathways with a variety of cellular responses either in culture or after transplantation; for instance, some reports use only insulin and epidermal growth factor [41], whereas some others add also triiodothyronin, hydrocortisone, and cholera toxin [14,20], all of which stimulate different signaling pathways and might affect the balance between cell proliferation and differentiation. Finally, some authors suggested the use of airlifted cultures, in order to increase differentiation in vitro [45,46], but airlifting could induce cell differentiation at the expense of stem cell selfrenewals, resulting in stem cell loss [45,47]. To be successful, a limbal culture must contain a sufficient number of the keratinocyte stem cells essential for long-term corneal renewal rather than a well-organized stratified epithelium [39].…”

“…The interplay between stem cells, the surrounding microenvironment, and external forces (representing the niche) needs to be elucidated before stem cell-based therapies are applied in clinics. Cell behavior is not only governed by pure chemical signals [45]. Tissue architecture and mechanical forces are overarching signals that govern cell decisions: cell matrix and cell-cell adhesion, organization of the cytoskeleton, and tensional forces that keep individual cells and the whole tissue in a certain shape, all represent architectural signals [62][63][64].…”