Figure 6.

HSPs 27 and 70 are released into culture medium by brain tumor cell lines under normal and heat shock conditions. The cell lines listed were left untreated (dark hatched bars) or were heat stressed (42°C, 1 h; light striped bars). Media were exchanged after heat shock, and cells recovered for 24 h. Media were then harvested for ELISA analyses for HSP27 (A) and HSP70 (B) using commercial kits. Statistical differences in HSP output were determined using t tests, with the p values indicated by asterisks. Those unmarked were not significant. SDs of replicate measurements were always <10% of the average and would be essentially unreadable as error bars; thus, they are not shown.