Western blot analysis of full length LASV NP, Josiah (LIV), produced in E. coli and stored for one year at -80oC in formulation buffer. LASV NP is commonly expressed and proteolytically cleaved into 2 shorter polypeptides of ~ 42 and 28 kDa, respectively. This product cleavage is observed in E. coli and in mammalian cells. After one year of storage the 3 polypeptide forms are detected by anti-HIS MAb (lane 2) and the 62 kDa full length (FL) and the 42 kDa fragment are detected by the murine anti-LASV NP N-terminus specific MAb 1474 (lane 3). Ladder (lane 1) is MagicMark XP WB standard.