FcγRIIB is an immune checkpoint limiting the activity of Treg-targeting antibodies in the tumor microenvironment

David A. Knorr; Lucas Blanchard; Rom S. Leidner; Shawn M. Jensen; Ryan Meng; Andrew Jones; Carmen Ballesteros-Merino; Richard B. Bell; Maria Baez; Alessandra Marino; David Sprott; Carlo B. Bifulco; Brian Piening; Rony Dahan; Juan C. Osorio; Bernard A. Fox; Jeffrey V. Ravetch

doi:10.1158/2326-6066.CIR-23-0389

FcγRIIB is an immune checkpoint limiting the activity of Treg-targeting antibodies in the tumor microenvironment

David A. Knorr, Lucas Blanchard, Rom S. Leidner, Shawn M. Jensen, Ryan Meng, Andrew Jones, Carmen Ballesteros-Merino, Richard B. Bell, Maria Baez, Alessandra Marino, David Sprott, Carlo B. Bifulco, Brian Piening, Rony Dahan, Juan C. Osorio, Bernard A. Fox, Jeffrey V. Ravetch^*

^*Corresponding author for this work

Department of Systems Immunology

Research output: Contribution to journal › Article › peer-review

1 Citation (Scopus)

Abstract

Preclinical murine data indicate that Fc-dependent depletion of intratumoral regulatory T cells (Tregs) is a major mechanism of action of anti–CTLA-4. However, the two main antibodies administered to patients (Ipilimumab and Tremelimumab) do not recapitulate these effects. Here, we investigate the underlying mechanisms responsible for the limited Treg depletion observed with these therapies. Using an immunocompetent murine model humanized for CTLA-4 and Fcγ receptors (FcγRs), we show that Ipilimumab and Tremelimumab exhibit limited Treg depletion in tumors. Immune profiling of the tumor microenvironment (TME) in both humanized mice and humans revealed high expression of the inhibitory Fc receptor, FcγRIIB, which limits antibody-dependent cellular cytotoxicity/phagocytosis (ADCC/ADCP). Blocking FcγRIIB in humanized mice rescued the Treg-depleting capacity and antitumor activity of Ipilimumab. Furthermore, Fc engineering of antibodies targeting Treg-associated targets (CTLA-4 or CCR8) to minimize FcγRIIB binding significantly enhanced Treg depletion, resulting in increased antitumor activity across various tumor models. Our results define the inhibitory FcγRIIB as an immune checkpoint limiting antibody-mediated Treg depletion in the TME, and demonstrate Fc engineering as an effective strategy to overcome this limitation and improve the efficacy of Treg-targeting antibodies.

Original language	English
Pages (from-to)	322-333
Number of pages	12
Journal	Cancer Immunology Research
Volume	12
Issue number	3
Early online date	26 Dec 2023
DOIs	https://doi.org/10.1158/2326-6066.CIR-23-0389
Publication status	Published - 4 Mar 2024

Bibliographical note

The authors would like to thank P. Smith, B. Bhagwandin-Colisi, A. Martin Mozqueda, E. Lam and R. Peraza for maintaining the humanized mouse strains and all the members of the J.V.R. laboratory for excellent technical assistance and helpful feedback. This work was supported by following grants from the National Institutes of Health (NIH): UL1TR001866 and KL2TR001865 from the National
Center for Advancing Translational Sciences NIH Clinical and Translational Science Award Program, D.A.K.; K08CA248966 to D.A.K.; R35CA196620, R01CA244327 and P01CA190174 to J.V.R.; MSK Specialized Program of Research Excellence in Bladder Cancer P50CA221745 through a Developmental Research Program Award; and the National Cancer Institute Cancer Center Support Grant P30CA008748. The content is solely the responsibility of the authors and does not necessarily
represent the official views of the NIH. C.B-M., S.M.J., R.S.L., and B.A.F. would like to thank the Harder Family, Robert W. Franz, Elsie Franz Finley, the Murdock Trust, the Chiles Foundation, Nancy Lematta. R.S.L. is also supported by Bristol Myers Squibb IO-ON. Graphical abstract and schematics were created with ioRender.com.

All Science Journal Classification (ASJC) codes

General Medicine

Access to Document

10.1158/2326-6066.CIR-23-0389Licence: CC BY-NC-ND

https://doi.org/10.1101/2023.01.19.522856Licence: CC BY-NC-ND

Cite this

Knorr, D. A., Blanchard, L., Leidner, R. S., Jensen, S. M., Meng, R., Jones, A., Ballesteros-Merino, C., Bell, R. B., Baez, M., Marino, A., Sprott, D., Bifulco, C. B., Piening, B., Dahan, R., Osorio, J. C., Fox, B. A., & Ravetch, J. V. (2024). FcγRIIB is an immune checkpoint limiting the activity of Treg-targeting antibodies in the tumor microenvironment. Cancer Immunology Research, 12(3), 322-333. https://doi.org/10.1158/2326-6066.CIR-23-0389

@article{69b6f9640b2b43f2ad2d1ee5e0326b17,

title = "FcγRIIB is an immune checkpoint limiting the activity of Treg-targeting antibodies in the tumor microenvironment",

abstract = "Preclinical murine data indicate that Fc-dependent depletion of intratumoral regulatory T cells (Tregs) is a major mechanism of action of anti–CTLA-4. However, the two main antibodies administered to patients (Ipilimumab and Tremelimumab) do not recapitulate these effects. Here, we investigate the underlying mechanisms responsible for the limited Treg depletion observed with these therapies. Using an immunocompetent murine model humanized for CTLA-4 and Fcγ receptors (FcγRs), we show that Ipilimumab and Tremelimumab exhibit limited Treg depletion in tumors. Immune profiling of the tumor microenvironment (TME) in both humanized mice and humans revealed high expression of the inhibitory Fc receptor, FcγRIIB, which limits antibody-dependent cellular cytotoxicity/phagocytosis (ADCC/ADCP). Blocking FcγRIIB in humanized mice rescued the Treg-depleting capacity and antitumor activity of Ipilimumab. Furthermore, Fc engineering of antibodies targeting Treg-associated targets (CTLA-4 or CCR8) to minimize FcγRIIB binding significantly enhanced Treg depletion, resulting in increased antitumor activity across various tumor models. Our results define the inhibitory FcγRIIB as an immune checkpoint limiting antibody-mediated Treg depletion in the TME, and demonstrate Fc engineering as an effective strategy to overcome this limitation and improve the efficacy of Treg-targeting antibodies.",

author = "Knorr, {David A.} and Lucas Blanchard and Leidner, {Rom S.} and Jensen, {Shawn M.} and Ryan Meng and Andrew Jones and Carmen Ballesteros-Merino and Bell, {Richard B.} and Maria Baez and Alessandra Marino and David Sprott and Bifulco, {Carlo B.} and Brian Piening and Rony Dahan and Osorio, {Juan C.} and Fox, {Bernard A.} and Ravetch, {Jeffrey V.}",

note = "The authors would like to thank P. Smith, B. Bhagwandin-Colisi, A. Martin Mozqueda, E. Lam and R. Peraza for maintaining the humanized mouse strains and all the members of the J.V.R. laboratory for excellent technical assistance and helpful feedback. This work was supported by following grants from the National Institutes of Health (NIH): UL1TR001866 and KL2TR001865 from the National Center for Advancing Translational Sciences NIH Clinical and Translational Science Award Program, D.A.K.; K08CA248966 to D.A.K.; R35CA196620, R01CA244327 and P01CA190174 to J.V.R.; MSK Specialized Program of Research Excellence in Bladder Cancer P50CA221745 through a Developmental Research Program Award; and the National Cancer Institute Cancer Center Support Grant P30CA008748. The content is solely the responsibility of the authors and does not necessarily represent the official views of the NIH. C.B-M., S.M.J., R.S.L., and B.A.F. would like to thank the Harder Family, Robert W. Franz, Elsie Franz Finley, the Murdock Trust, the Chiles Foundation, Nancy Lematta. R.S.L. is also supported by Bristol Myers Squibb IO-ON. Graphical abstract and schematics were created with ioRender.com. ",

year = "2024",

month = mar,

day = "4",

doi = "10.1158/2326-6066.CIR-23-0389",

language = "English",

volume = "12",

pages = "322--333",

journal = "Cancer Immunology Research",

issn = "2326-6066",

publisher = "American Association for Cancer Research Inc.",

number = "3",

}

Knorr, DA, Blanchard, L, Leidner, RS, Jensen, SM, Meng, R, Jones, A, Ballesteros-Merino, C, Bell, RB, Baez, M, Marino, A, Sprott, D, Bifulco, CB, Piening, B, Dahan, R, Osorio, JC, Fox, BA & Ravetch, JV 2024, 'FcγRIIB is an immune checkpoint limiting the activity of Treg-targeting antibodies in the tumor microenvironment', Cancer Immunology Research, vol. 12, no. 3, pp. 322-333. https://doi.org/10.1158/2326-6066.CIR-23-0389

TY - JOUR

T1 - FcγRIIB is an immune checkpoint limiting the activity of Treg-targeting antibodies in the tumor microenvironment

AU - Knorr, David A.

AU - Blanchard, Lucas

AU - Leidner, Rom S.

AU - Jensen, Shawn M.

AU - Meng, Ryan

AU - Jones, Andrew

AU - Ballesteros-Merino, Carmen

AU - Bell, Richard B.

AU - Baez, Maria

AU - Marino, Alessandra

AU - Sprott, David

AU - Bifulco, Carlo B.

AU - Piening, Brian

AU - Dahan, Rony

AU - Osorio, Juan C.

AU - Fox, Bernard A.

AU - Ravetch, Jeffrey V.

N1 - The authors would like to thank P. Smith, B. Bhagwandin-Colisi, A. Martin Mozqueda, E. Lam and R. Peraza for maintaining the humanized mouse strains and all the members of the J.V.R. laboratory for excellent technical assistance and helpful feedback. This work was supported by following grants from the National Institutes of Health (NIH): UL1TR001866 and KL2TR001865 from the National Center for Advancing Translational Sciences NIH Clinical and Translational Science Award Program, D.A.K.; K08CA248966 to D.A.K.; R35CA196620, R01CA244327 and P01CA190174 to J.V.R.; MSK Specialized Program of Research Excellence in Bladder Cancer P50CA221745 through a Developmental Research Program Award; and the National Cancer Institute Cancer Center Support Grant P30CA008748. The content is solely the responsibility of the authors and does not necessarily represent the official views of the NIH. C.B-M., S.M.J., R.S.L., and B.A.F. would like to thank the Harder Family, Robert W. Franz, Elsie Franz Finley, the Murdock Trust, the Chiles Foundation, Nancy Lematta. R.S.L. is also supported by Bristol Myers Squibb IO-ON. Graphical abstract and schematics were created with ioRender.com.

PY - 2024/3/4

Y1 - 2024/3/4

N2 - Preclinical murine data indicate that Fc-dependent depletion of intratumoral regulatory T cells (Tregs) is a major mechanism of action of anti–CTLA-4. However, the two main antibodies administered to patients (Ipilimumab and Tremelimumab) do not recapitulate these effects. Here, we investigate the underlying mechanisms responsible for the limited Treg depletion observed with these therapies. Using an immunocompetent murine model humanized for CTLA-4 and Fcγ receptors (FcγRs), we show that Ipilimumab and Tremelimumab exhibit limited Treg depletion in tumors. Immune profiling of the tumor microenvironment (TME) in both humanized mice and humans revealed high expression of the inhibitory Fc receptor, FcγRIIB, which limits antibody-dependent cellular cytotoxicity/phagocytosis (ADCC/ADCP). Blocking FcγRIIB in humanized mice rescued the Treg-depleting capacity and antitumor activity of Ipilimumab. Furthermore, Fc engineering of antibodies targeting Treg-associated targets (CTLA-4 or CCR8) to minimize FcγRIIB binding significantly enhanced Treg depletion, resulting in increased antitumor activity across various tumor models. Our results define the inhibitory FcγRIIB as an immune checkpoint limiting antibody-mediated Treg depletion in the TME, and demonstrate Fc engineering as an effective strategy to overcome this limitation and improve the efficacy of Treg-targeting antibodies.

AB - Preclinical murine data indicate that Fc-dependent depletion of intratumoral regulatory T cells (Tregs) is a major mechanism of action of anti–CTLA-4. However, the two main antibodies administered to patients (Ipilimumab and Tremelimumab) do not recapitulate these effects. Here, we investigate the underlying mechanisms responsible for the limited Treg depletion observed with these therapies. Using an immunocompetent murine model humanized for CTLA-4 and Fcγ receptors (FcγRs), we show that Ipilimumab and Tremelimumab exhibit limited Treg depletion in tumors. Immune profiling of the tumor microenvironment (TME) in both humanized mice and humans revealed high expression of the inhibitory Fc receptor, FcγRIIB, which limits antibody-dependent cellular cytotoxicity/phagocytosis (ADCC/ADCP). Blocking FcγRIIB in humanized mice rescued the Treg-depleting capacity and antitumor activity of Ipilimumab. Furthermore, Fc engineering of antibodies targeting Treg-associated targets (CTLA-4 or CCR8) to minimize FcγRIIB binding significantly enhanced Treg depletion, resulting in increased antitumor activity across various tumor models. Our results define the inhibitory FcγRIIB as an immune checkpoint limiting antibody-mediated Treg depletion in the TME, and demonstrate Fc engineering as an effective strategy to overcome this limitation and improve the efficacy of Treg-targeting antibodies.

UR - http://www.scopus.com/inward/record.url?scp=85186960136&partnerID=8YFLogxK

U2 - 10.1158/2326-6066.CIR-23-0389

DO - 10.1158/2326-6066.CIR-23-0389

M3 - Article

SN - 2326-6066

VL - 12

SP - 322

EP - 333

JO - Cancer Immunology Research

JF - Cancer Immunology Research

IS - 3

ER -

FcγRIIB is an immune checkpoint limiting the activity of Treg-targeting antibodies in the tumor microenvironment

Abstract

Bibliographical note

All Science Journal Classification (ASJC) codes

Access to Document

Other files and links

Fingerprint

Cite this