RT Journal Article
SR Electronic
T1 Collagen types I and III in giant papillae of vernal keratoconjunctivitis.
JF British Journal of Ophthalmology
JO Br J Ophthalmol
FD BMJ Publishing Group Ltd.
SP 482
OP 485
DO 10.1136/bjo.79.5.482
VO 79
IS 5
A1 A Leonardi
A1 G Abatangelo
A1 R Cortivo
A1 A G Secchi
YR 1995
UL http://bjo.bmj.com/content/79/5/482.abstract
AB AIMS--The objective of this study was to investigate alterations in conjunctival collagen and proteoglycans in the conjunctival giant papillae of patients with vernal keratoconjunctivitis (VKC). METHODS--Tissue samples from tarsal giant papillae of seven eyes from five patients with VKC, and five tarsal conjunctival samples from five normal patients were obtained. Tissues were processed and stained with haematoxylin and eosin, Van Gieson, trichromic Mallory, toluidine blue, Alcian blue, and alkaline Giemsa. Collagen extraction was performed in acetic acid and pepsin, total collagen was quantified using hydroxy-proline levels, and collagen types I and III were analysed by gel electrophoresis (SDS-PAGE). Proteoglycans were quantified using uronic acid levels. RESULTS--Histological evaluation showed a significant increase of mast cells in the epithelium (0/mm2 v 147/mm2, p < 0.01) and in the stroma (5.1/mm2 v 80/mm2, p < 0.01) of VKC patients. Collagen fibres were thicker and arranged irregularly, with the total amount significantly increased. Owing to an increased percentage of type III collagen, the ratio of collagen types I to III was decreased. Proteoglycans were also reduced in VKC samples. CONCLUSION--The well known morphological abnormalities observed in VKC correspond to alterations in the ratio between collagens and proteoglycans, and between different types of collagen. The greatly increased number of mast cells found in these tissues suggests an active role for these cells in the abnormal connective tissue metabolism observed in VKC.