HARNESSING 68GA-NOTA-RITUXIMAB IN RADIOIMMUNOTHERAPY (RIT) : REVOLUTIONIZING CANCER TREATMENT
Abstract
ABSTRACT
Radioimmunotherapy (RIT) represents a ground-breaking approach in cancer treatment of non-Hodgkin lymphoma (NHL), combining the specificity of monoclonal antibody with radioactive nucleotide. Rituximab, is a chimeric monoclonal antibody directed against B-lymphocyte specific antigen CD20, which is used for the treatment of B-cell malignancies. However, the effectiveness of rituximab is limited partly due to treatment resistance. The aim of this study is to develop the radiolabelled of rituximab to enhance the activity. Rituximab was conjugated with p-SCN-Bn-NOTA (1:10 and 1:50) and the pure conjugated rituximab was collected by using the preparative high performance liquid chromatography (HPLC). The conjugated was radiolabelled with 68Ga and purified by using PD-10 column. The quality control parameters such as pH, radiochemical purity (RCP), stability against time and serum challenge of 68Ga-NOTA-Rituximab were determined and the conditions were optimized. The RCP of ⁶⁸Ga-NOTA-Rituximab at 1:10 ratio was 97.34 ± 0.16% before purification and increased to 99.63 ± 0.16 % after purification. Likewise, the RCP of rituximab labelled at a 1:50 ratio was 89.02 ± 2.24% before purification and improved to 99.06 ± 0.01% post-purification. Additionally, the labelled rituximab remained stable for up to five hours under both serum and non-serum conditions, maintaining RCP of over 95%. From this study, we conclude that the rituximab was successfully conjugated with the p-SCN-Bn-NOTA and subsequently purified by using preparative HPLC, later radiolabelled with 68Ga. In vitro stability studies with 68Ga-NOTA-Rituximab with and without serum of up to 5 hours exhibited greater than 95% RCP. Further studies in pre-treated animal of NHL would confirm the potential of this 68Ga-NOTA-Rituximab for PET imaging of NHL.
ABSTRAK
Radioimunoterapi (RIT) mewakili pendekatan terobosan dalam rawatan kanser limfoma bukan Hodgkin (NHL), menggabungkan kekhususan antibodi monoklonal dengan nukleotida radioaktif. Rituximab, adalah antibodi monoklonal chimeric yang ditujukan terhadap antigen spesifik B-limfosit CD20, yang digunakan untuk rawatan keganasan sel B. Walau bagaimanapun, keberkesanan rituximab adalah terhad sebahagiannya disebabkan oleh rintangan rawatan. Matlamat kajian ini adalah untuk membangunkan radiolabelled rituximab untuk meningkatkan aktiviti. Rituximab telah dikonjugasikan dengan p-SCN-Bn-NOTA (1:10 dan 1:50) dan rituximab konjugasi tulen dikumpulkan dengan menggunakan kromatografi cecair prestasi tinggi persediaan (HPLC). Terkonjugasi telah dilabel radio dengan 68Ga dan disucikan dengan menggunakan lajur PD-10. Parameter kawalan kualiti seperti pH, ketulenan radiokimia (RCP), kestabilan melawan masa dan cabaran serum 68Ga-NOTA-Rituximab telah ditentukan dan keadaan telah dioptimumkan. RCP ⁶⁸Ga-NOTA-Rituximab pada nisbah 1:10 ialah 97.34 ± 0.16% sebelum penulenan dan meningkat kepada 99.63 ± 0.16 % selepas penulenan. Begitu juga, RCP rituximab yang dilabelkan pada nisbah 1:50 ialah 89.02 ± 2.24% sebelum penulenan dan bertambah baik kepada 99.06 ± 0.01% selepas penulenan. Selain itu, rituximab berlabel kekal stabil sehingga lima jam di bawah kedua-dua keadaan serum dan bukan serum, mengekalkan RCP melebihi 95%. Daripada kajian ini, kami menyimpulkan bahawa rituximab berjaya dikonjugasikan dengan p-SCN-Bn-NOTA dan kemudiannya disucikan dengan menggunakan HPLC persediaan, kemudian dilabel radio dengan 68Ga. Kajian kestabilan in vitro dengan 68Ga-NOTA-Rituximab dengan dan tanpa serum sehingga 5 jam menunjukkan lebih daripada 95% RCP. Kajian lanjut dalam haiwan pra-rawatan NHL akan mengesahkan potensi 68Ga-NOTA-Rituximab ini untuk pengimejan PET NHL.
