Detection of Active Form of Transforming Growth Factor‐β in Cerebrospinal Fluid of Patients with Glioma

We examined transforming growth factor‐β (TGF‐β) activity in cerebrospinal fluid of 39 patients with various brain tumors, and found it in 10 glioma cases that had lesions related to subarachnoid space or ventricle. In one glioma case, TGF‐β detected on admission disappeared after radiation and chemotherapy. We confirmed that five glioma cell lines produced TGF‐β, and that four of them produced active form of TGF‐β directly. The active form of TGF‐β was also identified from cerebrospinal fluid before the acidification treatment in two cases. The calculated contents were 110 ng/ml and 18 ng/ml. These results indicate that active form of TGF‐β is directly produced by tumor cells in patients with glioma, and may contribute to immunodeficiency of the host.