Yes, I remember when I first come across this macrophage switch, in 2018 I believe. I can't find the original post, but a site was promoting using maraviroc based on this from the paper Pfizer published on their results (which was someone attempting to explain but my first encounter with it). This was from feb 2019.
https://investorshub.advfn.com/boards/read_ms...=146534948
Here is an image I (sightly modified in red from before)
https://investorshub.advfn.com/boards/read_ms...=146534948
Quote:Blocking ccr5 turns cells from tumor promoting to tumor fighting—beating cancer at its own game:
https://www.cell.com/cancer-cell/fulltext/S15...16)30087-3
This person trying to put into layman’s terms
https://adventuresinlivingterminallyoptimisti...maraviroc/
Quote:One of the cell types in the innate immune system is the macrophage. Macrophages can either be tumor fighting (“M1-subtype”) or tumor helping (“M2-subtype”). Discovering ways to control macrophages and switch which sub-type they are is an intense area of current research.
In CRC, macrophages within the tumor (“tumor-associated macrophages (TAMs)”) are often of the “tumor promoting” M2-subtype. An area of active research has been to switch (or as scientists say, “repolarize”) these macrophages into M1-subtype tumor fighters. As M1-subtype tumor fighters and members of the innate immune system, macrophages can either attack cancer cells directly or serve as intermediaries to facilitate attack by the adaptive immune system.
Scientists have discovered that one of the master switches for determining whether a macrophage is tumor promoting (M2-subtype) vs. tumor fighting (M1-subtype) is the “CCR5 receptor”. This research has been recently published in the journal Cancer Cell. The exciting thing is that by blocking the CCR5 receptor with a CCR5 antagonist (e.g. Maraviroc), tumor promoting (M2-subtype) macrophages in CRC metastases can be switch (“repolarized”) into M1-subtype tumor fighters!
This not only can initiate direct innate immune system attack on tumors but it also has impacts on chemoresistance of these same tumors! Why is chemoresistance impacted? Recent studies have shown that cytotoxic chemotherapies promote recruitment of tumor promoting macrophages into the tumor – and this is one immune system aspect of chemoresistance. Switching these macrophages into M1-subtype tumor fighters may get rid of this resistance mechanism and also attack the tumor with its own “defense”!
Here is an image I (sightly modified in red from before)
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