The company Riptide Biosciences (Vallejo, CA, USA) designed a linear peptide that binds to CD206. The peptide, named RP-182 (sequence: KFRKAFKRFF) consists of alternating hydrophobic and hydrophilic aminoacids. Because the peptide also binds to RelB and CD47, the selectivity of systemically administered RP-182 for M2 TAMs remains to be seen. Interestingly, in a congress abstract the peptide was recently reported to induce phagocytosis and apoptosis in M2 mouse macrophages. This activity could be linked to the conformational change of CD206 produced by RP-182.
Sable R., Jaynes J., Ronzetti M., Guzman W., Knotts Z., Val N., de Morgan J., Yates C., Bolormaa B., Rudloff U. Abstract B49: Precision targeting of M2-like macrophages by the innate defense regulator RP-182 in pancreatic cancer and noncancerous diseases. Cancer Res. 2019;79:B49.
Scodeller, P., Simón-Gracia, L., Kopanchuk, S. et al. Precision Targeting of Tumor Macrophages with a CD206 Binding Peptide. Sci Rep 7, 14655 (2017). https://doi.org/10.1038/s41598-017-14709-x