Anti-Hu antibodyassociated paraneoplastic neurological syndromes (Hu-PNSs) are severe and often precede the detection of a malignancy, usually small-cell lung cancer. In Hu-PNS, it is hypothesized that neuronal cells are destroyed by T cells targeted against HuD, a protein expressed by small-cell lung cancer cells and neurons. There is only limited evidence for the existence of HuD-specific T cells. To detect these T cells in the blood of Hu-PNS patients, we employed 3 highly sensitive assays that included T cell stimulation with dendritic cells (DCs) to specifically expand the number of any HuD-specific T cells. A total of 17 Hu-PNS patients were tested with 1 or more of the following 3 assays: (1) tetramer staining after stimulation of T cells with conventionally generated DCs (n 9), (2) interleukin (IL)-13 enzyme-linked immunosorbent spot (ELISpot; n 3), IL-4 and IL-5 and interferon (IFN)γ multiplex cytokine bead array (n 2) to assay cytokine production by T cells after stimulation with conventionally generated DCs, and (iii) IFN-γ ELISpot and tetramer staining after T cell stimulation with accelerated co-cultured DCs (n 11). No circulating HuD-specific T cells were found. We suggest that either autoaggressive T cells in Hu-PNS are not targeted against HuD or that their numbers in the blood are too low for detection by highly sensitive techniques.

anti-Hu, CD8 + T cell, HuD-specific T cell, immune response, paraneoplastic neurological syndrome,
Department of Neurology

de Jongste, A.H.C, de Graaf, M.T, Martinuzzi, E, van den Broek, P.D.M, Kraan, J, Lamers, C.H.J, … Smitt, P.S. (2012). Three sensitive assays do not provide evidence for circulating HuD-specific T cells in the blood of patients with paraneoplastic neurological syndromes with anti-Hu antibodies. Neuro-Oncology, 14(7), 841–848. doi:10.1093/neuonc/nos118