I was reading about mouse model deficiencies the other day and today the study popped up
Differential assembly of mouse and human tumor microenvironments
https://www.nature.com/articles/s41590-026-02505-7
It appeared to me that mice models may understate the positive effects of blocking ccr5.
So I had to ask "the crutch"
Anyone is welcome to break it down
do mouse models correspond with blocking ccr5. does the study show blocking ccr5 may be more effective in humans than mice models.
"The Crutch"
"While this study does not mention leronlimab by name, its data directly explain why CCR5-blocking therapies may behave differently—and potentially be more relevant or effective in humans than in standard mouse models.
Key Findings Regarding CCR5
Reduced in Mice:
CCR5 gene transcripts are significantly reduced in mouse tumor-infiltrating T cells compared to humans.
Protein Confirmation: This interspecies deficiency was explicitly confirmed at the physical protein level.
Interspecies Divergence: Human T cells express far more CCR5 within the tumor microenvironment than mouse T cells do.
Impact on Leronlimab Efficacy
Leronlimab is a monoclonal antibody designed to bind and block human CCR5. Because standard mouse models inherently lack a robust, human-like CCR5 network on their tumor-infiltrating T cells, mouse models do not fully correspond with human CCR5 biology.
Consequently, any preclinical trial testing a CCR5 blocker in standard mice is highly likely to underrepresent the drug's true impact. In humans, where the CCR5 pathway is highly active on T cells, blocking it has a much larger biological footprint to exploit, making the therapeutic strategy potentially far more effective in human patients than mouse data would suggest.
The study identified that the widest cross-species gaps in chemokine expression and T-cell-recruiting receptor profiles occur in four specific tumor types: colorectal cancer (CRC), breast carcinoma (BRCA), pancreatic ductal adenocarcinoma (PDAC), and melanoma (MEL). These cancers show significant human-mouse differences in CCR5 signaling, with mouse models failing to replicate the robust, complex, and sometimes immune-excluded environments seen in human patients".
PS I also asked if it may under represent the effects in mice on liver fibrosis
but who knows
"The data in the Walsh Medical Media leronlimab fibrosis study likely underrepresents therapeutic effectiveness due to lower CCR5 receptor expression in mouse models compared to humans. While leronlimab showed significant reductions in fibrosis in STAM and \(CCl/4} models, human liver diseases exhibit higher target density and stronger macrophage-driven inflammation, suggesting greater potential efficacy.
Differential assembly of mouse and human tumor microenvironments
https://www.nature.com/articles/s41590-026-02505-7
It appeared to me that mice models may understate the positive effects of blocking ccr5.
So I had to ask "the crutch"
Anyone is welcome to break it down
do mouse models correspond with blocking ccr5. does the study show blocking ccr5 may be more effective in humans than mice models.
"The Crutch"
"While this study does not mention leronlimab by name, its data directly explain why CCR5-blocking therapies may behave differently—and potentially be more relevant or effective in humans than in standard mouse models.
Key Findings Regarding CCR5
Reduced in Mice:
CCR5 gene transcripts are significantly reduced in mouse tumor-infiltrating T cells compared to humans.
Protein Confirmation: This interspecies deficiency was explicitly confirmed at the physical protein level.
Interspecies Divergence: Human T cells express far more CCR5 within the tumor microenvironment than mouse T cells do.
Impact on Leronlimab Efficacy
Leronlimab is a monoclonal antibody designed to bind and block human CCR5. Because standard mouse models inherently lack a robust, human-like CCR5 network on their tumor-infiltrating T cells, mouse models do not fully correspond with human CCR5 biology.
Consequently, any preclinical trial testing a CCR5 blocker in standard mice is highly likely to underrepresent the drug's true impact. In humans, where the CCR5 pathway is highly active on T cells, blocking it has a much larger biological footprint to exploit, making the therapeutic strategy potentially far more effective in human patients than mouse data would suggest.
The study identified that the widest cross-species gaps in chemokine expression and T-cell-recruiting receptor profiles occur in four specific tumor types: colorectal cancer (CRC), breast carcinoma (BRCA), pancreatic ductal adenocarcinoma (PDAC), and melanoma (MEL). These cancers show significant human-mouse differences in CCR5 signaling, with mouse models failing to replicate the robust, complex, and sometimes immune-excluded environments seen in human patients".
PS I also asked if it may under represent the effects in mice on liver fibrosis
but who knows
"The data in the Walsh Medical Media leronlimab fibrosis study likely underrepresents therapeutic effectiveness due to lower CCR5 receptor expression in mouse models compared to humans. While leronlimab showed significant reductions in fibrosis in STAM and \(CCl/4} models, human liver diseases exhibit higher target density and stronger macrophage-driven inflammation, suggesting greater potential efficacy.
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