Levels of transforming growth factor alpha (TGF‐a)in human cerebrospinal fluid

In this study, we investigated cerebrospinal fluid of patients with various neurologicalsymptoms for the presence of transforming growth factor alpha (TGF‐a). 41 samples ofcerebrospinal fluid were collected by lumbar puncture performed routinely due to the clinicalsuspicion of neurological disease from 22 females (age 15–80 years, median 42 years) and from19 males (age 18–82 years, median 48 years). A highly sensitive and specific radioimmunoassaywas used to determine the concentration of TGF‐a in the samples. The detection limit of the assaywas about 200 pg TGF‐a. There was no cross‐reactivity to human EGF. We showed CSF indeeddoes contain TGFa. As TGF‐a was detected in all 41 samples investigated, this growth factorappears to be a constant component of CSF. The mean concentration was 5.5 ng TGF‐a (S.D.±2.7 pg/ml, range 1.1 to 13.9 pg/ml). There was no significant correlation between TGF‐aconcentration in CSF and age (r=−0.006) and there was no significant differencebetween females (mean 5.8±3.10 pg/ml) and males (mean 5.2±1.96 pg/ml). No diagnosis wasover represented in patients with TGF‐a concentrations above or below 1 S. D. off the mean.However, highest concentrations of TGF‐a were found in the group of patients with peripheralneurological sensory dysfunctions and polyneuropathy. We conclude that TGF‐a is not only aconstant component of human cerebrospinal fluid in adults but could also be significantly involvedin the pathophysiology of various neurological diseases. The earlier hypothesis that TGF‐a couldmainly have a role in brain development needs hence to be re‐evaluated.