Abstract: A method for the solubilization and recovery of plasmodial parasite protective antigenic factors from associated starting plasmodial parasite material, comprising forming an aqueous suspension of the starting parasite material and associated insoluble protective antigenic factors, adding a detergent to disperse the insoluble antigenic factors, and recovering the solubilized plasmodial parasite protective antigenic factors. A immunorganic composition made by the inventive method is also disclosed.

Abstract: A method for the solubilization and recovery of insoluble parasite protective antigenic factors associated with parasite material comprising solubilizing the antigenic factors with a non-ionic detergent and separating the solubilized material from undispersed residual material. The purified protective antigenic factors are useful as vaccines, particularly against malaria, and as diagnostic agents.

Abstract: Apparatus for holding a bag open comprising an arch, a pair of retaining members for receiving the ends of the arch and holding the arch in a vertical position, means for securing a part of the periphery of the open end of a bag to the arch, and a base member for controlling the separation between the retaining members and for holding another part of the periphery of the bag against the ground.