fibrin and Conjunctival-Diseases

The purpose of this study was to compare the use of autologous fibrin to human amniotic membrane (HAM) as a scaffold in cultivating autologous conjunctiva for transplantation in treatment of conjunctival defect. An experimental study was performed using 18 adult New Zealand white strain rabbits which were divided into 3 groups. Each group consists of 6 rabbits. The conjunctiva on the temporal site was excised to create a conjunctival epithelial defect. The excised area in the Group 1 was transplanted with autologous conjunctiva cultivated on autologous fibrin; Group 2 was transplanted with autologous conjunctiva cultivated on HAM and Group 3 was left bare. The rabbits were followed up at regular intervals until 6 weeks. The mean period of complete conjunctival epithelization was 11.50 ± 8.22 days for the autologous fibrin group, 15.33 ± 11.80 days for the HAM group and 25.33 ± 5.32 days in the bare sclera group. The epithelization rate for the autologous fibrin group was faster compared to the other two groups. However all the results were not statistically significant (p value >0.05). There were no postoperative complications noted during the follow up. Autologous fibrin is comparable to HAM as a scaffold for cultivation of conjunctiva in the treatment of conjunctival defect.

Topics: Amnion; Animals; Autografts; Cell Proliferation; Conjunctiva; Conjunctival Diseases; Disease Models, Animal; Epithelial Cells; Fibrin; Graft Rejection; In Vitro Techniques; Rabbits; Tissue Culture Techniques; Tissue Engineering; Tissue Scaffolds

Acne rosacea is an idiopathic dermatologic disease that frequently produces conjunctival inflammation. The authors studied the histology and immunopathology of epibulbar conjunctival biopsy specimens from eight patients with ocular rosacea and compared the findings with those from conjunctiva from 13 normal individuals. The conjunctival epithelium in ocular rosacea was attenuated and infiltrated by inflammatory cells, mainly T-helper/inducer (CD4) cells, phagocytic cells, and antigen-presenting (CD14, Mac-1) cells. The difference between the normal control group and the rosacea group in the number of mononuclear cells forming these populations was statistically significant (P less than 0.01). The substantia propria of the rosacea specimens contained large subepithelial infiltrates of chronic inflammatory cells, and in some cases frank granuloma formation was evident. There was an overall mean increase of nearly all cell types, but especially of T-helper cells in the rosacea specimens compared with the controls. Interestingly, T-helper/inducer (CD4) cells, which were outnumbered by the T-suppressor (CD8) cells in the normal conjunctival epithelium (CD4/CD8 = 0.85), outnumbered the CD8-positive cells in the rosacea specimens (CD4/CD8 = 1.6). There also was a 3.5-fold increase of the CD4/CD8 ratio in the rosacea conjunctival stroma compared with the normal specimens. The mechanism involved in rosacea conjunctival inflammation resembles a type IV hypersensitivity reaction.

Topics: Aged; Aged, 80 and over; Antibodies, Monoclonal; Biopsy; CD4-Positive T-Lymphocytes; Complement System Proteins; Conjunctiva; Conjunctival Diseases; Female; Fibrin; Fluorescent Antibody Technique; Humans; Immunoglobulins; Inflammation; Male; Middle Aged; Rosacea; T-Lymphocytes, Helper-Inducer; T-Lymphocytes, Regulatory