Collagen XIV is an intrinsic regulator of corneal stromal structure and function.

Collagen XIV is poorly characterized in the body and the current knowledge of its function in the cornea is limited. In this work, the aim is to elucidate the role(s) of collagen XIV in regulating corneal stromal structure and function. Analysis of collagen XIV expression, temporal and spatial, was performed at different postnatal days (P) in wild type C57BL/6 (WT) mouse corneal stromas and after injury. Conventional collagen XIV null mice were used to inquire the roles that collagen XIV plays in fibrillogenesis, fibril packing, and tissue mechanics. Fibril assembly and packing as well as stromal organization were evaluated using transmission electron microscopy and second harmonic generation microscopy. Atomic force microscopy was used to assess stromal stiffness. Col14a1 mRNA expression was present at P4 - P10 and noted to decrease at P30. No immunoreactivity was noted at P150. Abnormal collagen fibril assembly with a shift towards larger diameter fibrils and increased interfibrillar spacing in the absence of collagen XIV was found. SHG microscopy showed impaired fibrillogenesis in the collagen XIV null stroma. Mechanical testing suggested that collagen XIV confers stiffness to stromal tissue. Expression of collagen XIV is upregulated following injury. Collagen XIV plays a regulatory role in corneal development and in the function of the adult cornea. The expression of collagen XIV is recapitulated during wound healing.