Germinal centre protein HGAL promotes lymphoid hyperplasia and amyloidosis via BCR-mediated Syk activation NATURE COMMUNICATIONS Romero-Camarero, I., Jiang, X., Natkunam, Y., Lu, X., Vicente-Duenas, C., Gonzalez-Herrero, I., Flores, T., Luis Garcia, J., McNamara, G., Kunder, C., Zhao, S., Segura, V., Fontan, L., Martinez-Climent, J. A., Javier Garcia-Criado, F., Theis, J. D., Dogan, A., Campos-Sanchez, E., Green, M. R., Alizadeh, A. A., Cobaleda, C., Sanchez-Garcia, I., Lossos, I. S. 2013; 4

Abstract

The human germinal centre-associated lymphoma gene is specifically expressed in germinal centre B-lymphocytes and germinal centre-derived B-cell lymphomas, but its function is largely unknown. Here we demonstrate that human germinal centre-associated lymphoma directly binds to Syk in B cells, increases its kinase activity on B-cell receptor stimulation and leads to enhanced activation of Syk downstream effectors. To further investigate these findings in vivo, human germinal centre-associated lymphoma transgenic mice were generated. Starting from 12 months of age these mice developed polyclonal B-cell lymphoid hyperplasia, hypergammaglobulinemia and systemic reactive amyloid A (AA) amyloidosis, leading to shortened survival. The lymphoid hyperplasia in the human germinal centre-associated lymphoma transgenic mice are likely attributable to enhanced B-cell receptor signalling as shown by increased Syk phosphorylation, ex vivo B-cell proliferation and increased RhoA activation. Overall, our study shows for the first time that the germinal centre protein human germinal centre-associated lymphoma regulates B-cell receptor signalling in B-lymphocytes which, without appropriate control, may lead to B-cell lymphoproliferation.

View details for DOI 10.1038/ncomms2334

View details for Web of Science ID 000316614600008

View details for PubMedID 23299888

View details for PubMedCentralID PMC3545406