PURPOSE: The accessory lacrimal glands are assumed to contribute to the 
production of tear fluid, but little is known about their function. The goal of 
this study was to conduct an analysis of gene expression by glands of Wolfring 
that would provide a more complete picture of the function of these glands.
METHODS: Glands of Wolfring were isolated from frozen sections of human eyelids 
by laser microdissection. RNA was extracted from the cells and hybridized to 
gene expression arrays. The expression of several of the major genes was 
confirmed by immunohistochemistry.
RESULTS: Of the 24 most highly expressed genes, 9 were of direct relevance to 
lacrimal function. These included lysozyme, lactoferrin, tear lipocalin, and 
lacritin. The glands of Wolfring are enriched in genes related to protein 
synthesis, targeting, and secretion, and a large number of genes for proteins 
with antimicrobial activity were detected. Ion channels and transporters, 
carbonic anhydrase, and aquaporins were abundantly expressed. Genes for control 
of lacrimal function, including cholinergic, adrenergic, vasoactive intestinal 
polypeptide, purinergic, androgen, and prolactin receptors were also expressed 
in gland of Wolfring.
CONCLUSIONS: The data suggest that the function of glands of Wolfring is similar 
to that of main lacrimal glands and are consistent with secretion electrolytes, 
fluid, and protein under nervous and hormonal control. Since these glands 
secrete directly onto the ocular surface, their location may allow rapid 
response to exogenous stimuli and makes them readily accessible to topical 
drugs.