Myofibroblasts in the normal conjunctival surface.

• PURPOSE: To investigate the occurrence of myofibroblasts (MFBs) in the normal conjunctival surface and to evaluate any anatomical and time-related variations. METHODS: MFBs were screened among healthy individuals (35 eyes) by collecting impression cytology (IC) samples from the bulbar conjunctiva. A cohort of volunteers (12 eyes) was followed for 1 year by taking two to five imprints every month. MFBs were identified by immunohistochemical localization of the MFB marker alpha-smooth-muscle actin (alpha-SMA). RESULTS: Using a filter imprint technique, MFBs were found consistently in 94% of samples from the conjunctival surface of participating individuals. The overall MFB levels, expressed as percentage of all cells on the filter, were highest in March-May [mean 4.1%, standard deviation (SD) +/- 1.5] and lowest in December-February (mean 1.2%, SD +/- 0.5). The difference was statistically significant [p < 0.0005, Friedman test, one-way repeated measures analysis of variance (anova)]. Moreover, there was a clear divergence of MFB density between the nasal, temporal, superior and inferior bulbar conjunctiva (mean 1.7%, 1.9%, 22% and 9.7%, respectively). CONCLUSION: MFBs, known as a cellular constituent of granulation tissue in wound healing, occur in the normal conjunctival surface, which is a novel finding. Our results also show that MFB level follows a seasonal variation pattern in a temperate climate, increasing in April-September and decreasing in October-March. This variation might reflect a degree of a transient or ongoing state of tissue repair after conjunctival trauma or stress caused by exposure to environmental factors.

Nyckelord

Actins

metabolism

Adolescent

Adult

Aged

Conjunctiva

cytology

metabolism

Female

Fibroblasts

cytology

metabolism

Fluorescent Antibody Technique

Indirect

Follow-Up Studies

Humans

In Situ Hybridization

Fluorescence

Male

Microscopy

Fluorescence

Middle Aged

Polyploidy

Seasons

Young Adult

Publikations- och innehållstyp

ref (ämneskategori)

art (ämneskategori)