C-C motif chemokine 11 also known as eosinophil chemotactic protein and eotaxin-1 is a protein that in humans is encoded by the CCL11 gene. This gene is encoded on three exons and is located on chromosome 17.

Increased CCL11 levels in blood plasma are associated with aging in mice and humans. Additionally, it has been demonstrated that exposing young mice to CCL11 or the blood plasma of older mice decreases their neurogenesis and cognitive performance on behavioral tasks thought to be dependent on neurogenesis in the hippocampus.

Higher plasma concentrations of CCL11 have been found in current cannabis users compared to past users and those who had never used. CCL11 has also been found in higher concentrations in people suffering from schizophrenia; cannabis is a known trigger of schizophrenia.