Chemokines and transplant outcome

•Intragraft and peripheral chemokines drive immune response in solid organ transplantation.•Circulating level of chemokines, in particular CXCL10 and CXCL9, is associated with graft fate.•Pre-transplant measurement of CXCL10 and CXCL9 predicts graft rejection.•Chemokines retain high potentiality as good predictive non-invasive biomarkers for transplantation surveillance and outcome.

Improving long-term management, life-quality and outcome of transplant recipients continues to be a challenge. The impact of highly chemoattractant proteins as chemokines on transplant outcome is undeniable. These immunoactive molecules are critical in a wide variety of physiological and pathological processes, such as immunosurveillance, inflammation, infection, cancer, and rejection or tolerance after organ transplantation. Chemokines, playing an essential role in immune cell recruitment and localization within the graft, mirror the complex processes occurring in host-graft dialogue. In particular, the system of inflammatory chemokines and their receptors is modulated throughout all stages of transplantation and its inhibition counteracts rejection processes. The increase in chemokine expression at gene or protein level is, indeed, associated to multiorgan rejection. Thus, chemokines could serve as markers for risk of organ dysfunction/rejection and outcome predictors. This review intends to summarize chemokine function in transplantation and particularly focuses onto proinflammatory molecules such as CXC chemokines, which mediate early graft rejection in different organs and warrant consideration as predictors of outcome. The potentiality of chemokines – CXCL10 in particular – as systemic, robust, non-invasive, reliable and reproducible biomarkers for post-transplantation surveillance is addressed. Ideally, chemokines, as potential tools to predict and improve outcome, could give clinicians the opportunity to ameliorate patients' life-quality.