PURPOSE: Tears are known to have antimicrobial properties. The authors investigated the presence of the antibacterial enzyme phospholipase A2 (PLA2) in tears and lacrimal glands. METHODS: The catalytic activity of PLA2 and the amount of pancreatic group 1 PLA2 and nonpancreatic group 2 PLA2 were measured in homogenates of eight human lacrimal glands from autopsied subjects and in tears from four healthy volunteers. The localization of PLA2s in lacrimal gland sections was studied by immunohistochemistry. Skeletal muscle was used as a control. RESULTS: The catalytic activity of PLA2 was significantly higher in lacrimal glands than in skeletal muscle. Immunochemical analysis showed significantly higher amounts of group 2 PLA2 in lacrimal gland than in skeletal muscle homogenates. Group 1 PLA2 was present in trace amounts only. The concentration of group 2 PLA2 in tears was high (1451.3 micrograms/l) compared to that in the serum of healthy individuals (3.7 micrograms/l). By immunohistochemistry, a granular reaction of group 2 PLA2 was localized in the glandular cells of lacrimal glands. The apical cytoplasm of many duct cells also was labeled. CONCLUSIONS: The lacrimal glands secreted nonpancreatic group 2 PLA2, which most likely acts as an antiinfectious factor in tears.
PURPOSE: Tears are known to have antimicrobial properties. The authors investigated the presence of the antibacterial enzyme phospholipase A2 (PLA2) in tears and lacrimal glands. METHODS: The catalytic activity of PLA2 and the amount of pancreatic group 1 PLA2 and nonpancreatic group 2 PLA2 were measured in homogenates of eight human lacrimal glands from autopsied subjects and in tears from four healthy volunteers. The localization of PLA2s in lacrimal gland sections was studied by immunohistochemistry. Skeletal muscle was used as a control. RESULTS: The catalytic activity of PLA2 was significantly higher in lacrimal glands than in skeletal muscle. Immunochemical analysis showed significantly higher amounts of group 2 PLA2 in lacrimal gland than in skeletal muscle homogenates. Group 1 PLA2 was present in trace amounts only. The concentration of group 2 PLA2 in tears was high (1451.3 micrograms/l) compared to that in the serum of healthy individuals (3.7 micrograms/l). By immunohistochemistry, a granular reaction of group 2 PLA2 was localized in the glandular cells of lacrimal glands. The apical cytoplasm of many duct cells also was labeled. CONCLUSIONS: The lacrimal glands secreted nonpancreatic group 2 PLA2, which most likely acts as an antiinfectious factor in tears.
Authors: Masaaki Fujita; Kan Zhu; Chitose K Fujita; Min Zhao; Kit S Lam; Mark J Kurth; Yoko K Takada; Yoshikazu Takada Journal: J Biol Chem Date: 2014-11-14 Impact factor: 5.157
Authors: Heikki Peuravuori; Osmo Kari; Sirje Peltonen; Valtteri V Aho; Jukka M Saari; Yrjö Collan; Marko Määttä; K Matti Saari Journal: Graefes Arch Clin Exp Ophthalmol Date: 2004-06-26 Impact factor: 3.117
Authors: Heikki Peuravuori; Valtteri V Aho; Heikki J Aho; Yrjö Collan; K Matti Saari Journal: Graefes Arch Clin Exp Ophthalmol Date: 2005-07-26 Impact factor: 3.117
Authors: Sin Man Lam; Louis Tong; Xinrui Duan; U Rajendra Acharya; Jen Hong Tan; Andrea Petznick; Markus R Wenk; Guanghou Shui Journal: J Lipid Res Date: 2014-07-03 Impact factor: 5.922