TNF-α production by patients with FHL compared with healthy donors. Polyclonal NK-cell populations from 4 different healthy donors, patients with FHL3 (UPNs 249, 237, 225, and 289), and patients with FHL2 (UPNs 210, 235, 256, and 314) were stimulated overnight by plastic-bound anti-NKp30 mAb (A) or by coculture with 221 cell line (B). Supernatants were harvested and analyzed by specific ELISA for their TNFα content. Bars represent the mean of values within a group. Differences among groups were not significant in panel A (P > .05), whereas both FHL3 and FHL2 were different (P < .05) from the healthy group in panel B (Kruskal-Wallis test).