Cu-DOTA-ECL1i

Cu-DOTA-ECL1i is a radiotracer composed of ECL1i (extracellular loop 1 inverso; d(LGTFLKC)), which is an allosteric peptidic modulator of CC chemokine receptor type 2 (CCR2)[1]. It's primarily used for positron emission tomography (PET) imaging to detect CCR2 expression in various inflammatory conditions and diseases[3][5]. The radiotracer is created by conjugating the ECL1i peptide with DOTA (a chelator) and then radiolabeling it with copper-64 (64Cu)[4]. This creates 64Cu-DOTA-ECL1i, which can effectively bind to CCR2 receptors that are expressed on inflammatory cells[5]. The specific binding of this radiotracer to CCR2 allows for noninvasive visualization of inflammation in various tissues. ## Development and Applications 64Cu-DOTA-ECL1i has been studied in several clinical contexts: 1. **Pulmonary Inflammation and Fibrosis**: Research has shown that 64Cu-DOTA-ECL1i can effectively detect lung inflammation by targeting CCR2-expressing cells involved in the inflammatory process[7]. Studies in mouse models of lung injury demonstrated that the radiotracer accumulates in inflamed lung tissue at levels 2.5 times higher than in control lungs[4]. 2. **Myocardial Infarction**: Clinical trials are investigating the use of 64Cu-DOTA-ECL1i for imaging cellular activity in the heart after a heart attack or due to other inflammatory heart conditions[8]. 3. **Cancer Detection**: Studies have examined the radiotracer's ability to bind to CCR2 receptors in human head and neck cancer tissue, showing specific binding to cancerous areas that correlates with CCR2 immunohistochemical staining[10]. ## Technical Characteristics The radiochemical purity of 64Cu-DOTA-ECL1i used in animal studies is typically 98% or greater[4]. The mean specific activity is approximately 55.5 MBq/nmol, which enables trace amounts (approximately 70 pmol) to be injected for in vivo studies[4]. The radiotracer has demonstrated stability in mouse serum both in vitro (98.2% ± 2.1 at 37°C for 1 hour) and in vivo in serum (96.5% ± 1.1) and lung tissue (95.6% ± 3.0)[4]. ## Clinical Trials As of May 2025, there are ongoing clinical trials evaluating 64Cu-DOTA-ECL1i for: 1. Detection of CCR2 expression in patients with fibrotic lung diseases[7] 2. Evaluation of CCR2 in patients after myocardial infarction[8] 3. Assessment of CCR2 expression in head and neck cancer patients[10] These trials aim to determine the diagnostic quality and CCR2 expression detection rate of 64Cu-DOTA-ECL1i-PET/CT images, evaluate the relationship between radiotracer uptake and immunohistochemical staining for chemokine receptors, and assess the potential of the radiotracer to track inflammatory cells in various diseases[7][8][10].

Other names

64Cu-DOTA-ECL1i