Wacław Szybalski's contribution to immunotherapy: HGPRT mutation & HAT selection as first steps to gene therapy and hybrid techniques in mammalian cells

•We describe Wacław Szybalski's fundamental contribution to gene therapy.•His 1962 PNAS paper documents first successful gene repair in mammalian cells.•HAT selection procedure was originally reported in this 1962 paper.•HAT selection was essential to develop monoclonal antibody technique.•HAT selection is still used in various areas of molecular biology and medicine.

In this report we describe Wacław Szybalski's fundamental contribution to gene therapy and immunotherapy. His 1962 PNAS paper (Szybalska and Szybalski, 1962) documented the first successful gene repair in mammalian cells. Furthermore, this was also the first report on the HAT selection method used later in many applications. Most importantly, somatic cell fusion and HAT selection were subsequently used to develop monoclonal antibody technology, which contributed significantly to the progress of today's medicine.