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Immunity | Surgery | Surgical Procedures, Operative


Background: Inducible costimulator (ICOS) is rapidly upregulated with T-cell stimulation and may represent an escape pathway for T-cell costimulation in the setting of CD40/CD154 costimulation blockade. Induction treatment exhibited no efficacy in a primate renal allograft model, but rodent transplant models suggest that the addition of delayed ICOS/ICOS-L blockade may prolong allograft survival and prevent chronic rejection. Here, we ask whether ICOS-Ig treatment, timed to anticipate ICOS upregulation, prolongs NHP cardiac allograft survival or attenuates pathogenic alloimmunity.

Methods: Cynomolgus monkey heterotopic cardiac allograft recipients were treated with alphaCD40 (2C10R4, d0-90) either alone or with the addition of delayed ICOS-Ig (d63-110).

Results: Median allograft survival was similar between ICOS-Ig + alphaCD40 (120 days, 120-125 days) and alphaCD40 (124 days, 89-178 days) treated animals, and delayed ICOS-Ig treatment did not prevent allograft rejection in animals with complete CD40 receptor coverage. Although CD4(+) TEM cells were decreased in peripheral blood (115 +/- 24) and mLNs (49 +/- 1.9%) during ICOS-Ig treatment compared with monotherapy (214 +/- 27%, P = 0.01; 72 +/- 9.9%, P = 0.01, respectively), acute and chronic rejection scores and kinetics of alloAb elaboration were similar between groups.

Conclusions: Delayed ICOS-Ig treatment with the reagent tested is probably ineffective in modulating pathogenic primate alloimmunity in this model.

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Copyright © 2018 The Author(s). Transplantation Direct. Published by Wolters Kluwer Health, Inc. This is an open-access article distributed under the terms of the Creative Commons Attribution-Non Commercial-No Derivatives License 4.0 (CCBY-NC-ND), where it is permissible to download and share the work provided it is properly cited. The work cannot be changed in any way or used commercially without permission from the journal.

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Transplant Direct. 2018 Feb 2;4(2):e344. doi: 10.1097/TXD.0000000000000761. eCollection 2018 Feb. Link to article on publisher's site

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Transplantation direct

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Creative Commons License

Creative Commons Attribution-Noncommercial-No Derivative Works 4.0 License
This work is licensed under a Creative Commons Attribution-Noncommercial-No Derivative Works 4.0 License.