Important examples of trogocytosis mediated by mAbs
| Target Epitope . | mAb . | Key observations . |
|---|---|---|
| CD3 | Muromonab-CD3 (OKT3) | Early clinical report of antigenic modulation. In vitro experiments demonstrated requirements for monocytes and intact IgG.36,37 |
| CD5 | T101 | Loss of CD5 was induced by treatment of patients with CLL or cutaneous T-cell lymphoma with mAb T101. In vitro studies indicated FcγR on monocytes and intact IgG were required.38-44,75,76 |
| CD8 | Hit8a | When whole blood samples are probed with CD8 mAbs for standard flow cytometry analyses, CD8 is transferred to and internalized by monocytes and neutrophils.19,21,30 |
| CD20 | RTX (Rituxan) | Both mAbs promote in vivo and in vitro trogocytosis.8,12-14,17,18,20,22,52,55-58,61,64,67 |
| OFA (Arzerra) | ||
| CD20-6 | This type II CD20 mAb promotes trogocytosis.57 | |
| CD22 | Epratuzumab | Treatment of SLE patients with epratuzumab resulted in trogocytosis of CD22 and other cell surface proteins from circulating B cells.15,66 |
| CD25 | Daclizumab (Zenapax) | Treatment of patients with multiple sclerosis with daclizumab resulted in trogocytosis of CD25 from T cells.15 |
| CD33 | Gemtuzumab ozogamicin (Mylotarg) | Trogocytosis, mediated by FcγRIIb on LSECs, may explain why some patients who receive Mylotarg therapy experience severe liver damage.22,68-70,72 |
| EGF-R | Cetuximab (Erbitux) | Cetuximab mediates trogocytosis by monocytes of the EGF receptor on 3 different cell lines in vitro.18,77 |
| Her2/Neu | Trastuzumab (Herceptin) | Trastuzumab mediates trogocytosis by monocytes of the Her2/Neu antigen on a breast cancer cell line in vitro.18 |
| Target Epitope . | mAb . | Key observations . |
|---|---|---|
| CD3 | Muromonab-CD3 (OKT3) | Early clinical report of antigenic modulation. In vitro experiments demonstrated requirements for monocytes and intact IgG.36,37 |
| CD5 | T101 | Loss of CD5 was induced by treatment of patients with CLL or cutaneous T-cell lymphoma with mAb T101. In vitro studies indicated FcγR on monocytes and intact IgG were required.38-44,75,76 |
| CD8 | Hit8a | When whole blood samples are probed with CD8 mAbs for standard flow cytometry analyses, CD8 is transferred to and internalized by monocytes and neutrophils.19,21,30 |
| CD20 | RTX (Rituxan) | Both mAbs promote in vivo and in vitro trogocytosis.8,12-14,17,18,20,22,52,55-58,61,64,67 |
| OFA (Arzerra) | ||
| CD20-6 | This type II CD20 mAb promotes trogocytosis.57 | |
| CD22 | Epratuzumab | Treatment of SLE patients with epratuzumab resulted in trogocytosis of CD22 and other cell surface proteins from circulating B cells.15,66 |
| CD25 | Daclizumab (Zenapax) | Treatment of patients with multiple sclerosis with daclizumab resulted in trogocytosis of CD25 from T cells.15 |
| CD33 | Gemtuzumab ozogamicin (Mylotarg) | Trogocytosis, mediated by FcγRIIb on LSECs, may explain why some patients who receive Mylotarg therapy experience severe liver damage.22,68-70,72 |
| EGF-R | Cetuximab (Erbitux) | Cetuximab mediates trogocytosis by monocytes of the EGF receptor on 3 different cell lines in vitro.18,77 |
| Her2/Neu | Trastuzumab (Herceptin) | Trastuzumab mediates trogocytosis by monocytes of the Her2/Neu antigen on a breast cancer cell line in vitro.18 |
CLL, chronic lymphocytic leukemia; EGF-R, epidermal growth factor receptor; LSEC, liver sinusoidal endothelial cells; OFA, ofatumumab; RTX, rituximab; SLE, systemic lupus erythematosus.