Some scleroderma patients produce high titer antibody directed against human topoisomerase I (Shero et al., 1986). The immunoglobulin fraction was purified from these patients and shown to react specifically with the 100 kDa form of Topo I using Western blotting. The immune complexes produced with this reagent will bind [125I]-protein A. When intact topoisomerase I is used, a single polypeptide of 100 kDa was detected; however, sub-bands produced by proteolysis will also bind this reagent, as expected. The antibody is particularly useful as a Western blotting probe and can be used at high dilutions (>1:5,000). Cross reactivity of this antibody with other species has been demonstrated (with calf thymus). Important note about product use: Human topoisomerase I undergoes spontaneous degradation especially with repeat freezing/thawing. The activity of the enzyme is not affected significantly; however, sub-bands may be detectable in Western blotting experiments. This antibody may be used in immunoprecipitation experiments.
Unit Definition:
The Polyclonal Antibody to Human Topoiosomerase I concentration is in Western blotting units; one unit corresponds to a 1:1000 dilution of probe for a routine Western blot (1 ml). For example, 10 units of antibody will make 10 ml of diluted probe (to be added directly to a single blot).
Material Safety Data:
THIS PRODUCE IS NOT LICENSED OR APPROVED FOR ADMINISTRATION TO HUMANS OR TO ANIMALS OTHER THAN EXPERIMENTAL ANIMALS.
The antibody is shipped hydrated on wet ice. Store at -20°C.
Reference:
Shero, J.H. Bordwell, B., Rothfield, N.F. and Earnshaw, W.C. 1986. High titers of autoantibodies to topoisomerase I (Scl-70) in sera from scleroderma patients. Science231:737-740