Coimmunoprecipitation of soluble A34. HeLa cells were infected with vTF7-3 at an MOI of 5 and transfected with the indicated plasmids in the presence of AraC. The following day, cells were lysed, and lysates were immunoprecipitated with anti-B5 and protein G-Dynabeads. Immune complexes (A) and cell lysates (B) were analyzed by Western blotting with anti-V5, anti-B5, and anti-actin. The masses in kilodaltons and positions of marker proteins are shown on the left of the blots.