A method of culturing adherent cells in suspension is provided that includes culturing adherent cells on a first substrate in a first suspension, harvesting the adherent cells from the first substrate, and transfecting the harvested adherent cells using electro-poration. The method also includes, after the step of transfecting, suspending the transfected adherent cells in a second suspension. A dissolution process for dissolving the second microcarrier particle to harvest the cells or cell products is also provided. This dissolution process includes adding a chelator, such as EDTA, to the second suspension for a predetermined time to separate the cells from the second microcarrier; and isolating the cells or cell products from a remainder of the second suspension after the predetermined time. The dissolution process is performed without enzymes such as pectinase or protease.