A kit formulation for the preparation of [89Zr]Zr(oxinate)4 for PET cell tracking: White blood cell labelling and comparison with [111In]In(oxinate)3

Abstract

Background Advances in immunology and cell-based therapies are creating a need to track individual cell types, such as immune cells (neutrophils, eosinophils, chimeric antigen receptor (CAR) T cells, etc.) and stem cells. As the fate of administered cells remains largely unknown, nuclear imaging could determine the migration and survival of cells in patients. [ 89 Zr]Zr(oxinate) 4 , or [ 89 Zr]Zr-oxine, is a radiotracer for positron emission tomography (PET) that has been evaluated in preclinical models of cell tracking and could improve on [ 111 In]In-oxine, the current gold standard radiotracer for cell tracking by scintigraphy and single-photon emission computed tomography (SPECT), because of the better sensitivity, spatial resolution and quantification of PET. However, a clinically usable formulation of [ 89 Zr]Zr-oxine is lacking. This study demonstrates a 1-step procedure for preparing [ 89 Zr] Zr-oxine and evaluates it against [ 111 In]In-oxine in white blood cell (WBC) labelling. Methods Commercial [ 89 Zr]Zr-oxalate was added to a formulation containing oxine, a buffering agent, a base and a surfactant or organic solvent. WBC isolated from 10 human volunteers were radiolabelled with [ 89 Zr]Zr-oxine following a clinical radiolabelling protocol. Labelling efficiency, cell viability, chemotaxis and DNA damage were evaluated in vitro , in an intra-individual comparison against [ 111 In]In-oxine. Results An optimised formulation of [ 89 Zr]Zr-oxine containing oxine, polysorbate 80 and 4-(2-hydroxyethyl)-1-piperazineethanesulfonic acid (HEPES) was developed. This enabled 1-step radiolabelling of oxine with commercial [ 89 Zr]Zr-oxalate (0.1–25 MBq) in 5 min and radiotracer stability for 1 week. WBC labelling efficiency was 48.7 ± 6.3%, compared to 89.1 ± 9.5% ( P < 0.0001, n = 10) for [ 111 In]In-oxine. Intracellular retention of 89 Zr and cell viability after radiolabelling were comparable to 111 In. There were no significant differences in leukocyte chemotaxis or DNA damage between [ 89 Zr]Zr-oxine or [ 111 In]In-oxine. Conclusions, advances in knowledge and implications for patient care Our results demonstrate that [ 89 Zr]Zr-oxine is a suitable PET alternative to [ 111 In]In-oxine for WBC imaging. Our formulation allows rapid, stable, high-yield, single-step preparation of [ 89 Zr]Zr-oxine fro...

Optimisation of the Synthesis and Cell Labelling Conditions for [89Zr]Zr-oxine and [89Zr]Zr-DFO-NCS: a Direct In Vitro Comparison in Cell Types with Distinct Therapeutic Applications

“…However, a significant increase in the cell cycle arrest and apoptosis was detected. Man et al demonstrated that significant DNA damage is evident in white blood cells labelled with [ 89 Zr]Zr-oxine at 32.9 kBq/10 6 cells [24]. Patrick et al established that the majority of DNA damage is repaired at the 7-day time point [42].…”

“…Several parameters were investigated to improve the radiochemical conversion (RCC) from the original protocol [16,[24][25][26], as well as to minimise the timeframe of radioactive exposure. See supplementary.…”

“…1), which may help facilitate clinical translation. The currently available protocols for [ 89 Zr]Zr-oxine synthesis are characterised by a low overall radiochemical yield (RCY) and include cumbersome steps such as buffer exchange, chloroform extractions, evaporations and the usage of several buffers in the synthesis [16,[23][24][25][26].…”

The chemical tool-kit for molecular imaging with radionuclides in the age of targeted and immune therapy

“…This allows imaging of cell migration for as much as 1-2 weeks, since the radionuclide is largely retained by the labelled cells. A simplified, good manufacturing practice (GMP)-compatible kit-based method of producing the 89 Zr-oxine complex has been reported recently, [60] greatly enhancing the opportunity for wider use in clinical trials of cell-based therapy. An alternative approach to cell labelling is by conjugation of DFO-based zirconium-89 chelates [61] or iodine-124-prosthetic groups [62] (Fig.…”

Simplified 89Zr-Labeling Protocol of Oxine (8-Hydroxyquinoline) Enabling Prolonged Tracking of Liposome-Based Nanomedicines and Cells

“…Oxinates of the transition radiometals gallium-68, zirconium-89 and indium-111 ([ 68 Ga]Ga(oxinate) 3 , [ 89 Zr]Zr(oxinate) 4 , [ 111 In]In(oxinate) 3 ) are highly lipophilic molecules that can be incorporated into lipid-bilayered nanovesicles (liposomes) and living cells under neutral conditions. Using this mechanism, more recent studies disseminated [ 89 Zr]Zr(oxinate) 4 -related cell tracing by applying various labeling protocols from 60% to 97% labeling efficiency of the prelabeled oxinate [2][3][4][5][6] and complex liposome labeling by combining this method with a liposome-incorporated bifunctional chelator [7].…”