TABLE 1.
The role of BTK in signaling pathways in various cell types.
| Cell type | Via | Process in which BTK plays a role | References |
| B cell | BCR; TLR | Cytokine production (IL-6, TNFα, IFNγ, IL-10, IL-12) | Halcomb et al., 2008; Lee et al., 2008a; Corneth et al., 2016; von Borstel et al., 2019; Torke et al., 2020 |
| BCR; BAFFR; TLR | Proliferation, differentiation & immunoglobulin production | Wicker and Scher, 1986; Khan et al., 1995; Di Paolo et al., 2011; Haselmayer et al., 2019; von Borstel et al., 2019 | |
| BCR | Antigen presentation (via MHC-II) and co-stimulation (via CD86 and CD69) | Kenny et al., 2013; Haselmayer et al., 2019 | |
| BCR | Integrin-mediated adhesion of B cells to VCAM-1 and fibronectin | Spaargaren et al., 2003; de Rooij et al., 2012 | |
| BAFFR | Homeostatic B cell survival | Shinners et al., 2007; Schweighoffer et al., 2013 | |
| CXCR4; CXCR5; CCR7 | Chemotaxis and homing to and within lymphoid organs | de Gorter et al., 2007; de Rooij et al., 2012 | |
| IL-5R | Proliferation and differentiation | Hitoshi et al., 1993; Sato et al., 1994; Koike et al., 1995 | |
| Conventional DC | TLR7; TLR9 | IFN-β production | Li et al., 2014 |
| TLR4 | DC maturation and cytokine production | Kawakami et al., 2006; Natarajan et al., 2016 | |
| Plasmacytoid DC | TLR9 | Cytokine production (IFNα, TNFα and IL-6) and expression of CD40, CD86, and CD69 | Wang J. et al., 2014 |
| Mast cell | FcεRI | Degranulation and cytokine production (IL-2, IL-3, IL-4, TNFα, IL-6) | Hata et al., 1998; Chang et al., 2011; Iyer et al., 2011; Soucek et al., 2011 |
| FcγR | Degranulation and cytokine production (TNFα, IL-8, MCP-1) | Chang et al., 2011 | |
| Neutrophil | GM-CSFR/TLR | Maturation and function | Fiedler et al., 2011 |
| FcγR/TLR4 | Degranulation, oxidative burst, pathogen engulfment & cytokine production | Prezzo et al., 2019; Blez et al., 2020 | |
| Fpr-1 | fMLP-driven Mac-1-activation and infiltration into inflamed tissue | Gilbert et al., 2003; Volmering et al., 2016; Herter et al., 2018 | |
| PSGL-1 | E-selectin triggered activation of β2-integrin | Mueller et al., 2010; Yago et al., 2010 | |
| NLRP3 | Inflammasome activation and thereby IL-1β secretion | Ito et al., 2015; Liu et al., 2017 | |
| TREM-1 | Degranulation, oxidative burst and L-selectin shedding | Stadler et al., 2017 | |
| Basophil | FcεRI | Degranulation and cytokine production | Kneidinger et al., 2008; MacGlashan et al., 2011; Smiljkovic et al., 2017; Haselmayer et al., 2019 |
| Monocyte | FcγR | Cytokine production (TNFα, IL-6, MCP-1, IL-1β) | Chang et al., 2011; Di Paolo et al., 2011; Ren et al., 2016 |
| Macrophage | TLR2/4 | Microbicidal activity (via nitric oxide (NO) production), cytokine production (TNFα, IL-1β) and M1 polarization | Mukhopadhyay et al., 1999, 2002; Mangla et al., 2004; Ni Gabhann et al., 2014; de Porto et al., 2019 |
| FcγR | Cytokine production (TNFα, IL-6, IL-1β, MCP-1) | Chang et al., 2011; Di Paolo et al., 2011; Hartkamp et al., 2015 | |
| CD40 | Cytokine (IL-6, IL-8, TNFα, IL-10) and NO production | Mukhopadhyay et al., 1999; Hartkamp et al., 2015 | |
| DDX41 | IFN-type I response | Lee et al., 2015 | |
| NLRP3 | Inflammasome activation and thereby IL-1β secretion | Ito et al., 2015; Liu et al., 2017 | |
| M-CSFR | Survival | Melcher et al., 2008 | |
| Osteoclast | RANK | Maturation and differentiation | Lee et al., 2008b; Shinohara et al., 2008 |