<> "The repository administrator has not yet configured an RDF license."^^ . <> . . . "Development 68Ga trastuzumab Fab and bioevaluation by PET imaging in HER2/neu expressing breast cancer patients"^^ . "Introduction: Receptors on breast cancer cells play a crucial role in the management of patients. Trastuzumab is a widely used drug for the treatment of HER2/neu expressing tumors. ImmunoPET with trastuzumab is not feasible due to slow pharmacokinetics. Fragment of antigen-binding (Fab) radiolabeled with positron emitters can be used for immunoPET.\r\n\r\nMethods: Fab has been generated by papain digestion and conjugated with the bifunctional chelating agent NOTA. The SDS-PAGE and MALDI-TOF were used to see the integrity of Fab and conjugated Fab. In-vitro stability and target specificity for HER2/neu receptors were performed in plasma and receptor binding with bio-layer interferometry (BLI) techniques. Radiolabeling was standardized with 68GaCl3 and PET imaging was performed in seven patients showing 18F fluorodeoxyglucose (18F-FDG) uptake and correlated with HER2/neu expression by immunohistochemistry.\r\n\r\nResults: Fab production was optimized at molar ratio 23:1 of trastuzumab and papain at 37 °C with a constant stirrer at 850 rpm for 22-24 h, at pH 8. Conjugation with NOTA was standardized at molar ratio 1:25 of trastuzumab Fab and NOTA. Molecular mass of trastuzumab Fab-NOTA was found approximately 46.3 kDa (~1/3 of intact antibody). Trastuzumab Fab-NOTA showed radiolabelling efficiency of 48-70% with incubation time 15 min at 37-40 °C and pH 4.5-5.0. BLI demonstrated the affinity of trastuzumab, trastuzumab Fab and trastuzumab Fab-NOTA towards HER2/neu receptor with KD of <1pM, ~0.5nM and ~20nM, respectively. All immunohistochemistry proven patients showed uptake in primary breast lesion and lymph nodes.\r\n\r\nConclusion: Trastuzumab Fab-NOTA is suitable for radiolabelling with 68Ga and ImmunoPET imaging of HER2/neu receptor."^^ . "2022-04-01" . "43" . "4" . . "Wolters Kluwer"^^ . . . "Nuclear Medicine Communications "^^ . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . "Yogesh "^^ . "Rathore "^^ . "Yogesh Rathore "^^ . . "Ishita "^^ . "Laroiya"^^ . "Ishita Laroiya"^^ . . "Jaya "^^ . "Shukla "^^ . "Jaya Shukla "^^ . . "Tamanna "^^ . "Lakhanpal "^^ . "Tamanna Lakhanpal "^^ . . "Gurpreet "^^ . "Singh "^^ . "Gurpreet Singh "^^ . . "Amanjit"^^ . "Bal"^^ . "Amanjit Bal"^^ . . "B R "^^ . "Mittal "^^ . "B R Mittal "^^ . . "Harmandeep "^^ . "Singh "^^ . "Harmandeep Singh "^^ . . "Amar "^^ . "Deep "^^ . "Amar Deep "^^ . . "Rajender"^^ . "Kumar "^^ . "Rajender Kumar "^^ . . "Krishan Gopal "^^ . "Thakur "^^ . "Krishan Gopal Thakur "^^ . . . . . "HTML Summary of #2992 \n\nDevelopment 68Ga trastuzumab Fab and bioevaluation by PET imaging in HER2/neu expressing breast cancer patients\n\n" . "text/html" . . . "QR Microbiology"@en . .