Glycam1, short for glycosylation-dependent cell adhesion molecule 1, is a proteoglycan ligand for L-selectin. It is involved in modulating immune cell entry and has been associated with lymphocyte trafficking. It plays a role in the immune system and is also expressed in the mammary gland, suggesting functions in both immunological and lactation-related processes [2,3]. Genetic models, such as knockout mouse models, are valuable for studying its functions.

In a study on glaucoma in DBA/2J mice, a null allele of Glycam1 was generated. Radiation therapy usually inhibits monocyte entry into the optic nerve head, preventing retinal ganglion cell death and axon loss. However, DBA/2J mice with a Glycam1 null allele showed increased monocyte entry, as well as increased retinal ganglion cell death and axon loss after radiation therapy. This indicates that Glycam1 negatively regulates monocyte entry into the optic nerve head and contributes to radiation-based protection in glaucoma [1].

In conclusion, Glycam1 has a role in modulating immune cell entry, as demonstrated by the gene knockout study in glaucoma. Its function as a negative regulator of extravasation may lead to new therapeutic strategies for conditions involving inflammation. Additionally, its expression in the mammary gland suggests potential functions in lactation-related processes, which warrants further research [1,2,3].

References:

1. Williams, Pete A, Braine, Catherine E, Foxworth, Nicole E, Cochran, Kelly E, John, Simon W M. 2017. GlyCAM1 negatively regulates monocyte entry into the optic nerve head and contributes to radiation-based protection in glaucoma. In Journal of neuroinflammation, 14, 93. doi:10.1186/s12974-017-0868-8. https://pubmed.ncbi.nlm.nih.gov/28446179/

2. Groenen, M A, Dijkhof, R J, van der Poel, J J. . Characterization of a GlyCAM1-like gene (glycosylation-dependent cell adhesion molecule 1) which is highly and specifically expressed in the lactating bovine mammary gland. In Gene, 158, 189-95. doi:. https://pubmed.ncbi.nlm.nih.gov/7607540/

3. Nishimura, Toshihide. . Expression of potential lymphocyte trafficking mediator molecules in the mammary gland. In Veterinary research, 34, 3-10. doi:. https://pubmed.ncbi.nlm.nih.gov/12588680/