Ng agents used clinically. VLA-4 targeted novel molecular imaging 15900046 of MM has the potential to improve early-stage diagnosis and the management of patients receiving compounds that affect the tumor cells as well as the microenvironment. Here, we evaluated a VLA-4 targeted PET radiopharmaceutical, 64Cu-CB-TE1A1P-LLP2A, (Figure 1B) for PET imaging of VLA-4 positive murine myeloma 5TGM1 MM tumors. For the proof-of-principle imaging studies, we used the 5TGM1 mouse model of bone marrow disseminated mouse MM. The 5TGM1into-KaLwRij model originates from spontaneously developed MM in aged C57BL/KalwRij mice and has since been propagated by intravenous injection of BM cells from MM bearing mice, into young naive syngeneic recipients [24]. CellPET iImaging of Multiple MyelomaNT 157 uptake and AZ 876 supplier binding assays performed with 5TGM1 cells demonstrated receptor specific binding of the imaging probe. Tissue biodistribution and small animal PET/CT imaging studies demonstrated highly sensitive and specific uptake of the imaging probe by the subcutaneous (s.c.) and intra-peritoneal (i.p.) 5TGM1 tumors, and suspected tumor cells and associated inflammatory cells in the BM. Additionally, the imaging probe demonstrated high binding to the human MM cells RPMI-8226 in vitro that was significantly blocked (P,0.0001) in the presence of the cold targeting ligand. Pilot imaging studies in the orthotopic (intravenous, i.v.) mouse models of mouse (5TGM1) and human (RPMI8226) MM are ongoing.published mouse MM cell line 5TGM1 [28] (a gift from Dr. G. Mundy, Vanderbilt University, Nashville, Tennessee) was grown in DMEM supplemented with 10 fetal bovine serum, penicillin (100 U/ml) and streptomycin (50 mg/ml). Long term culture of the cells occurred in a water jacketed incubator at 37uC and 5 CO2. Assays were also carried out under these respective conditions.Flow CytometryPE-conjugated mAb to mouse CD49d (Integrin alpha 4) was purchased from eBioscience. 5TGM1 cells were prepared for flow cytometry by incubating cells with mAb followed by PBS washes. Data collection and analyses were performed on a FACScalibur flow cytometer (Becton Dickinson Immunocytometry Systems, Mountain View, California, USA).Materials and Methods Ethics StatementAll experiments involving the use of radioactive materials at Washington University were conducted under the authorization of the Radiation Safety Committee in accordance with the University’s Nuclear Regulatory Commission license. All animal studies were performed under the Guide for the Care and Use of Laboratory Animals under the auspices of the Washington University Animal Studies Committee. This study was approved by the Washington University Animal Studies Committee (Animal protocol # 20090058).In Vitro Cell Uptake AssayCell uptake assays were performed in murine 5TGM1 and human RPMI-8226 myeloma cells using 64Cu-CB-TE1A1PLLP2A to determine the sum of cell internalized and surfacebound fractions. Cells were grown in Iscoves MDM until 60275 confluent, harvested by mechanical dissociation, and re-suspended in the binding medium (phosphate buffered saline [PBS], 0.1 bovine serum albumin [BSA] and 1 mM Mn2+) in 1.5 mL microfuge tubes. A solution of 64Cu-CB-TE1A1P-LLP2A (0.1 nM) was added to the cell suspension. The samples were incubated for 60 min in a cell incubator (37uC, 5 CO2). To determine the in vitro VLA-4 binding specificity of 64Cu-CBTE1A1P-LLP2A, samples were co-incubated with ,200-fold excess of the unlabeled ligand, LLP2A. Af.Ng agents used clinically. VLA-4 targeted novel molecular imaging 15900046 of MM has the potential to improve early-stage diagnosis and the management of patients receiving compounds that affect the tumor cells as well as the microenvironment. Here, we evaluated a VLA-4 targeted PET radiopharmaceutical, 64Cu-CB-TE1A1P-LLP2A, (Figure 1B) for PET imaging of VLA-4 positive murine myeloma 5TGM1 MM tumors. For the proof-of-principle imaging studies, we used the 5TGM1 mouse model of bone marrow disseminated mouse MM. The 5TGM1into-KaLwRij model originates from spontaneously developed MM in aged C57BL/KalwRij mice and has since been propagated by intravenous injection of BM cells from MM bearing mice, into young naive syngeneic recipients [24]. CellPET iImaging of Multiple Myelomauptake and binding assays performed with 5TGM1 cells demonstrated receptor specific binding of the imaging probe. Tissue biodistribution and small animal PET/CT imaging studies demonstrated highly sensitive and specific uptake of the imaging probe by the subcutaneous (s.c.) and intra-peritoneal (i.p.) 5TGM1 tumors, and suspected tumor cells and associated inflammatory cells in the BM. Additionally, the imaging probe demonstrated high binding to the human MM cells RPMI-8226 in vitro that was significantly blocked (P,0.0001) in the presence of the cold targeting ligand. Pilot imaging studies in the orthotopic (intravenous, i.v.) mouse models of mouse (5TGM1) and human (RPMI8226) MM are ongoing.published mouse MM cell line 5TGM1 [28] (a gift from Dr. G. Mundy, Vanderbilt University, Nashville, Tennessee) was grown in DMEM supplemented with 10 fetal bovine serum, penicillin (100 U/ml) and streptomycin (50 mg/ml). Long term culture of the cells occurred in a water jacketed incubator at 37uC and 5 CO2. Assays were also carried out under these respective conditions.Flow CytometryPE-conjugated mAb to mouse CD49d (Integrin alpha 4) was purchased from eBioscience. 5TGM1 cells were prepared for flow cytometry by incubating cells with mAb followed by PBS washes. Data collection and analyses were performed on a FACScalibur flow cytometer (Becton Dickinson Immunocytometry Systems, Mountain View, California, USA).Materials and Methods Ethics StatementAll experiments involving the use of radioactive materials at Washington University were conducted under the authorization of the Radiation Safety Committee in accordance with the University’s Nuclear Regulatory Commission license. All animal studies were performed under the Guide for the Care and Use of Laboratory Animals under the auspices of the Washington University Animal Studies Committee. This study was approved by the Washington University Animal Studies Committee (Animal protocol # 20090058).In Vitro Cell Uptake AssayCell uptake assays were performed in murine 5TGM1 and human RPMI-8226 myeloma cells using 64Cu-CB-TE1A1PLLP2A to determine the sum of cell internalized and surfacebound fractions. Cells were grown in Iscoves MDM until 60275 confluent, harvested by mechanical dissociation, and re-suspended in the binding medium (phosphate buffered saline [PBS], 0.1 bovine serum albumin [BSA] and 1 mM Mn2+) in 1.5 mL microfuge tubes. A solution of 64Cu-CB-TE1A1P-LLP2A (0.1 nM) was added to the cell suspension. The samples were incubated for 60 min in a cell incubator (37uC, 5 CO2). To determine the in vitro VLA-4 binding specificity of 64Cu-CBTE1A1P-LLP2A, samples were co-incubated with ,200-fold excess of the unlabeled ligand, LLP2A. Af.
