SPP1 and type 1 diabetes mellitus: infection on the T1D phenotype between wild-type and knockout mice: while wild-type mice show increased T1D incidence after infection, in the absence of OPN, infection with the parasites decreases the incidence of the disease; ii) a higher parasitic load is observed in infected wild-type BMF at 48 h p. i., while no parasitic proliferation is observed in the NOD opn null mice; iii) discrete variations in the in vivo clinical phenotype as well as in parasite content at the infection sites are notable in the absence of OPN; and iv) p. i.