These sculptures represent the Malaria parasite (Plasmodium falciparum Merozoite). The smooth model shows the parasite just after it has entered a red blood cell. The spiky malaria shows the Plasmodium before. See here for more information about the life cycle of Malaria.
The artwork is 200,000 x larger than the actual parasite.
The first edition of the artwork was made especially for the charity Malaria No More. See image above of Bono promoting ‘Malaria No More’ charity and auction of Jerram’s Malaria sculpture in NYC. This work has recently been on display in the Museum of Art and Design, NYC and at the Heller Gallery, NYC.
The Wellcome Collection in London have acquired editions of these sculptures for their permanent collection.