The CD25-binding antibody daclizumab high-yield process (DAC HYP) is an interleukin (IL)-2 signal modulating antibody that shares primary amino acid sequence and CD25 binding affinity with Zenapax®, a distinct form of daclizumab, which was approved for the prevention of acute organ rejection in patients receiving renal transplants as part of an immunosuppressive regimen that includes cyclosporine and corticosteroids. Comparison of the physicochemical properties of the two antibody forms revealed the glycosylation profile of DAC HYP differs from Zenapax in both glycan distribution and the types of oligosaccharides, most notably high-mannose, galactosylated and galactose-α-1,3-galactose (α-Gal) oligosaccharides, resulting in a DAC HYP antibody material that is structurally distinct from Zenapax. Although neither antibody elicited complement-dependent cytotoxicity in vitro, DAC HYP antibody had significantly reduced levels of antibody-dependent cell-mediated cytotoxicity (ADCC).
View Article and Find Full Text PDFObjective: The objective of this study was to evaluate whether interleukin-2 (IL-2) receptor expression on CD56(bright) natural killer (NK) cells predicted CD56(bright) NK cell expansion and therapeutic response to daclizumab (DAC) in multiple sclerosis (MS).
Methods: DAC exposure, CD56(bright) NK cell counts, IL-2 receptor alpha (CD25) and beta (CD122) subunits, and new or enlarged lesions on brain MRI were measured in 64 subjects in a pharmacokinetic/pharmacodynamic substudy of the phase 2 CHOICE trial at multiple time points. Peripheral blood mononuclear cell (PBMC) samples were obtained from healthy subjects to assess the relationship among DAC treatment, intermediate affinity IL-2 signaling, and CD56(bright) NK cell expansion.
Although inhibiting interaction of beta(2) integrins with cognate immunoglobulin class adhesion receptor ligands is an effective neuroprotective strategy in small mammal models of stroke, the strategy has failed in human trials. A completely different antiadhesion receptor strategy was therefore rigorously tested in a model that may more closely approximate human reperfused stroke. Early leukoadhesive events in postischemic cerebral microvessels are mediated by upregulated selectin-class adhesion receptors on endothelial cells.
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