The chemokine receptor CXCR3 plays a central role in inflammation by mediating effector/memory T cell migration in various diseases; however, drugs targeting CXCR3 and other chemokine receptors are largely ineffective in treating inflammation. Chemokines, the endogenous peptide ligands of chemokine receptors, can exhibit so-called biased agonism by selectively activating either G protein–mediated or β-arrestin–mediated signaling after receptor binding. Biased agonists might be used as more targeted therapeutics to differentially regulate physiological responses, such as immune cell migration. To test whether CXCR3-mediated physiological responses could be segregated by G protein– and β-arrestin–mediated signaling, we identified and characterized small-molecule, biased agonists of the receptor. In a mouse model of T cell–mediated allergic contact hypersensitivity (CHS), topical application of a β-arrestin–biased, but not a G protein–biased, agonist potentiated inflammation. T cell recruitment was increased by the β-arrestin–biased agonist, and biopsies of patients with allergic CHS demonstrated coexpression of CXCR3 and β-arrestin in T cells. In mouse and human T cells, the β-arrestin–biased agonist was the most efficient at stimulating chemotaxis. Analysis of phosphorylated proteins in human lymphocytes showed that β-arrestin–biased signaling activated the kinase Akt, which promoted T cell migration. This study demonstrates that biased agonists of CXCR3 produce distinct physiological effects, suggesting discrete roles for different endogenous CXCR3 ligands and providing evidence that biased signaling can affect the clinical utility of drugs targeting CXCR3 and other chemokine receptors.

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Purpose Low- and middle-income countries disproportionately comprise 65% of cancer deaths. Cancer care delivery in resource-limited settings, especially low-income countries in sub-Saharan Africa, is exceedingly complex, requiring multiple modalities of diagnosis and treatment. Given the vast human, technical, and financial resources required, access to radiotherapy remains limited in sub-Saharan Africa. Through 2017, Rwanda has not had in-country radiotherapy services. The aim of this study was to describe the implementation and early outcomes of the radiotherapy referral program at the Butaro Cancer Centre of Excellence and to identify both successful pathways and barriers to care. Methods Butaro District Hospital is located in a rural area of the Northern Province and is home to the Butaro Cancer Centre of Excellence. We performed a retrospective study from routinely collected data of all patients with a diagnosis of cervical, head and neck, or rectal cancer between July 2012 and June 2015. Results Between 2012 and 2015, 580 patients were identified with these diagnoses and were potential candidates for radiation. Two hundred eight (36%) were referred for radiotherapy treatment in Uganda. Of those referred, 160 (77%) had cervical cancer, 31 (15%) had head and neck cancer, and 17 (8%) had rectal cancer. At the time of data collection, 101 radiotherapy patients (49%) were alive and had completed treatment with no evidence of recurrence, 11 (5%) were alive and continuing treatment, and 12 (6%) were alive and had completed treatment with evidence of recurrence. Conclusion This study demonstrates the feasibility of a rural cancer facility to successfully conduct out-of-country radiotherapy referrals with promising early outcomes. The results of this study also highlight the many challenges and lessons learned in providing comprehensive cancer care in resource-limited settings.