CD40-targeting KGYY15 peptides do not efficiently block the CD40–CD40L interaction

  • Damir Bojadzic
  • Peter BuchwaldEmail author

To the Editor: Co-signalling interactions, which include costimulatory and coinhibitory interactions and act as immune checkpoints, are important immunomodulatory therapeutic targets. Biological products that interfere with these interactions have achieved considerable clinical success in the treatment of cancer on the one hand, and autoimmune diseases and transplant recipients on the other. Alternatives to biological products are also being explored as they have the potential to lead to safer, less immunogenic, orally bioavailable agents; however, like all other protein–protein interactions, co-signalling interactions are challenging to target by smaller molecules [1]. Among these interactions, the one between CD40 and CD40 ligand (CD40L, also known as CD154) is of particular interest as a therapeutic target for the prevention of rejection in islet cell transplant recipients, as well as the prevention, or possibly even reversal, of type 1 diabetes. As published in Diabetologia [2],...


Contribution statement

PB conceived the study, analysed the data and wrote the manuscript; DB designed and performed the assays and contributed to the writing of the manuscript. Both authors contributed to drafting the article or revising it critically for important intellectual content and approved the version to be published. PB is the guarantor of this work and, as such, had full access to all the data in the study and takes responsibility for the integrity of the data and the accuracy of the data analysis.


This research received no specific grant from any funding agency in the public, commercial or not-for-profit sectors.

Duality of interest

The author(s) declare that they have no competing interests.


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Copyright information

© Springer-Verlag GmbH Germany, part of Springer Nature 2019

Authors and Affiliations

  1. 1.Diabetes Research Institute, Miller School of MedicineUniversity of MiamiMiamiUSA
  2. 2.Department of Molecular and Cellular Pharmacology, Miller School of MedicineUniversity of MiamiMiamiUSA

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