Updated project metadata. Tumors display oncofetal chondroitin sulfate (ofCS) glycosaminoglycans that support disease progression and dissemination. ofCS can be detected by the the Plasmodium falciparum derived VAR2CSA protein but the development of recombinant VAR2CSA as a clinical tool has proven challenging. Here, we performed AP-MS experiments with newly developed antibodies with ofCS specificity comparable to VAR2CSA, as well as recombinant VAR2CSA bait.