Supplementary Table 1. TTI-621 binds to human tumor cell lines Tumor Type Cell Line Binding EC50 (nM) Acute myeloid leukemia OCI-AML-2 262 B cell lymphoma Pfeiffer 493 HT 20 SU8 16 Toledo 23 SU4 90 SU6 32 NU1 31 SU16 14 Breast cancer SKBR3 461 Epidermoid carcinoma A431 136 Multiple myeloma H929 253 MM1s 171 T cell leukemia Jurkat T cell lymphoma HH 66 H9 34 Supplementary Table 1: Established human tumor cell lines were incubated with titrated amounts of biotinylated TTI-621, washed and stained with streptavidin-PE. Cells were then washed, fixed and analyzed by flow cytometry. EC50 values were generated by linear regression using a sigmoidal dose- response curve.

Supplementary Table 2. TTI-621 binds to human primary tumor samples Tumor Type Patient ID Binding EC50 (nM) Acute myeloid leukemia A1 161 A2 333 B-acute lymphoblastic leukemia B1 72 B2 80 B3 154 B4 106 B5 164 B6 109 B7 75 B8 299 B9 425 B10 807 Myelodysplastic syndrome M1 93 M2 83 T-acute lymphoblastic leukemia T1 77 T2 81 T3 97 T4 346 T5 176 Supplementary Table 2: Primary human tumor samples were incubated with titrated amounts of biotinylated TTI-621, washed and stained with streptavidin-PE. Cells were then washed, fixed and analyzed by flow cytometry. EC50 values were generated by linear regression using a sigmoidal dose-response curve.

Supplementary Table 3. TTI-621 binds to peripheral blood cells of healthy donors Cell type Binding EC50 (nM) CD4+ T cells 153 CD8+ T cells 168 B cells 123 NK cells 902 NKT cells 293 Platelets 57 Supplementary Table 3: Fresh heparinized whole blood from healthy donors (n=6) was erythrocyte-lysed. Cells were incubated with titrated amounts of biotinylated TTI-621 (0.24 nM-10 μM) or control IgG1 Fc, washed, and stained with streptavidin-PE. Cells were then washed, fixed and analyzed by flow cytometry. Cells were gated as live, single cells and defined as follows: B cells: CD3-CD20+, CD4+ T cells: CD3+CD4+, CD8+ T cells: CD3+CD4-, NK cells: CD3-CD56+, NKT cells: CD3+CD56+, platelets: CD45-CD41b+. EC50 values were generated by linear regression using a sigmoidal dose-response curve.

Supplementary Table 4: TTI-621 Potency In Vitro Tumor Type Sample Phagocytosis EC50 (nM) Acute myeloid leukemia OCI-AML-2 cell line 5 Patient sample A3 4 Patient sample A4 2 Patient sample A5 57 B cell lymphoma Pfeiffer cell line 8 Raji cell line 3 SUDHL6 cell line 0.5 SUDHL16 cell line 16 Toledo cell line Breast cancer SKBR3 cell line 23 Lung cancer A549 cell line Melanoma A375.S2 cell line Multiple myeloma MM.1s cell line 6 H929 cell line Patient sample M3 T cell leukemia Jurkat cell line 0.08 Supplementary Table 4: Phagocytosis of established human tumor cell lines and primary human tumor samples was assessed in the presence of titrated amounts of TTI-621. EC50 values were generated by linear regression using a sigmoidal dose-response curve.