High expression of 5-lipoxygenase in normal and malignant mantle zone B lymphocytes

• Main Authors: Sander Birgitta, Björkholm Magnus, Christensson Birger, Flygare Jenny, Spanbroek Rainer, Wang Xiao, Lisy Marcus-René, Mahshid Yilmaz, Habenicht Andreas JR, Claesson Hans-Erik
• Format: Article
• Language: English
• Published: BMC 2009-01-01
• Series: BMC Immunology
• Online Access: http://www.biomedcentral.com/1471-2172/10/2

<p>Abstract</p> <p>Background</p> <p>Human B lymphocytes can produce leukotriene B₄but the biological function of the 5-lipoxygenase (5-LO) pathway in B cells is unclear. In order to better understand and define the role of 5-LO in B cells, we investigated the expression of 5-LO mRNA and protein in subsets of B cells from human tonsils and different types of B cell lymphoma.</p> <p>Results</p> <p>Based on RT-PCR and western blot/immunohistochemical staining, with a polyclonal antibody raised against 5-LO, high expression of 5-LO was found in mantle zone B cells from tonsils. By contrast, only a weak expression of 5-LO was detected in germinal centre cells and no expression in plasma cells from tonsils. This pattern of 5-LO expression was preserved in malignant lymphoma with high expression in mantle B cell lymphoma (MCL) and weak or no expression in follicular lymphoma. Primary leukemized MCL, so called B-prolymphocytic leukaemia cells, and MCL cell lines also expressed 5-LO and readily produced LTB₄after activation.</p> <p>Conclusion</p> <p>The present report demonstrates the expression of 5-LO mainly in normal and malignant mantle zone B cells while the expression is low or absent in germinal centre B cells and plasma cells, indicating a role of the 5-LO pathway in B cells before the cells finally differentiate to plasma cells.</p>