- The X-linked lymphoproliferative-disease gene product SAP regulates signals induced through the co-receptor SLAM. Sayos, J., Wu, C., Morra, M., Wang, N., Zhang, X., Allen, D., van Schaik, S., Notarangelo, L., Geha, R., Roncarolo, M.G., Oettgen, H., De Vries, J.E., Aversa, G., Terhorst, C. Nature (1998)