An assay of transepithelial migration was performed as above, but using unlabeled T cells, and with blocking mAbs as appropriate.
The Tedder laboratory mapped and characterized CD22 ligand binding domains using a panel of anti-CD22 mAbs and found that several mAbs, such as HB22.7, completely blocked interaction with its ligand on all cell types examined, while other anti-CD22 mAbs, such as HB22.27, exhibited no blocking ability [ 12].
Certain mAbs such as trastuzumab or rituximab exert direct cytotoxic effects by blocking the biological signalling activities of tumour antigens associated with cell-function and proliferation [ 98, 99].
Based on the pivotal role of TNF-α in the pathogenesis of RA [ 4], two classes of biologic drugs to block this cytokine have been developed: a soluble TNF-α receptor (etanercept) and TNF-binding monoclonal antibodies (mAbs) such as infliximab, adalimumab, golimumab, or certolizumab [ 5, 6].
Anti-CD22 mAbs, such as HB22.7, that bind the two amino-terminal Ig domains of CD22 and specifically block the interaction of CD22 with its ligand induce proliferative responses in primary B-cells, but apoptotic responses in neoplastic B-cells [ 8, 15].
The selection of which variable loop targeted mAb to mimic using these strategies is now simplified by this approach: mAbs such as 3074 targeting highly conserved epitopes are now easily distinguishable from less prevalent mAbs such as 447-52D (Figure 3) to enhance the neutralization information emerging from testing of the mAbs against small panels of viruses.
Epitope conservation ranged from <5% of known HIV viruses for the motif recognized by mAbs such as 268 to 87% for the motif recognized by mAbs such as 3074 (Table 2).
Other gH-only-specific mAbs such as MG-1A2 and MG-2E6 [20] gave similar results to MG-9B10.
Different mAbs have been developed in early clinical phases including anti-CD40 mAbs such as lucatumumab, dacetuzumab, or mAb directed against HM1.24, the XmAb 5592 [ 38].
The first approach involves mAbs, such as cetuximab (Erbitux® a chimeric anti-EGFR antibody), panitumumab (Vectibix a fully humanized anti-EGFR antibody), raised against the extracellular domain of EGFR to block ligand binding and receptor activation, and trastuzumab (Herceptin®), a recombinant humanized mAb also targeted against the extracellular domain of HER2.
