Immunocytochemistry of the ocular surface after different techniques of limbal stem cell transplantation for chronic chemical burns

Aim To compare the immunocytochemistry (ICC) on impression cytology of corneal surface epithelium after simple limbal epithelial transplantation (SLET) and conjunctival-limbal autograft (CLAU). Methods A prospective study of 20 patients above 1 year of age with chronic chemical burns, who underwent limbal stem cell transplantation (LSCT). They were divided equally in group A (SLET) and group B (CLAU). ICC was done for cytokeratin 3 (CK3) and cytokeratin 19 (CK19), preoperatively and postoperatively at 6 months. Results Four cases were excluded due to inadequate cellularity in preoperative or postoperative samples. On ICC analysis, in the remaining 16 patients mean CK3 and CK19 positivity changed from 2.06%+/- 1.73% and 83.56%+/- 8.69% preoperatively to 70.62%+/- 13.2% (p<0.0001) and 5.93%+/- 4.17% (p<0.0001), respectively, at 6 months post LSCT. In group A (8 patients) mean CK3 and CK19 positivity of 2%+/- 1.8% and 84.5%+/- 8.4% preoperatively changed to 70%+/- 13.8% (p<0.0001) and 6.25%+/- 5.1% (p<0.0001) at 6 months respectively. While in group B (8 patients), it was 2.12%+/- 1.7% and 82.62%+/- 9.4% preoperatively and 71.25%+/- 013.5% (p<0.0001) and 5.62%+/- 3.2% (p<0.0001) at 6 months. There was no significant difference in expression of CK3 (p=0.084) and CK19 (p=0.744) post SLET or CLAU. Three patients with complete reversion had clear corneas at 6 months. Conclusion Reversion of the epithelium to corneal phenotype was documented post LSCT with no difference in expression of CK3 between the two procedures (SLET/CLAU).