Limits...
Expression analysis of G Protein-Coupled Receptors in mouse macrophages.

Lattin JE, Schroder K, Su AI, Walker JR, Zhang J, Wiltshire T, Saijo K, Glass CK, Hume DA, Kellie S, Sweet MJ - Immunome Res (2008)

Bottom Line: The GPCR repertoire expressed by bone marrow-derived macrophages and thioglycollate-elicited peritoneal macrophages had some commonality, but there were also several GPCRs preferentially expressed by either cell population.The constitutive or regulated expression in macrophages of several GPCRs identified in this study has not previously been described.Future studies on such GPCRs and their agonists are likely to provide important insights into macrophage biology, as well as novel inflammatory pathways that could be future targets for drug discovery.

View Article: PubMed Central - HTML - PubMed

Affiliation: Cooperative Research Centre for Chronic Inflammatory Diseases and Special Research Centre for Functional and Applied Genomics, Institute for Molecular Bioscience, University of Queensland, Brisbane, Queensland, 4072, Australia. j.lattin@imb.uq.edu.au

ABSTRACT

Background: Monocytes and macrophages express an extensive repertoire of G Protein-Coupled Receptors (GPCRs) that regulate inflammation and immunity. In this study we performed a systematic micro-array analysis of GPCR expression in primary mouse macrophages to identify family members that are either enriched in macrophages compared to a panel of other cell types, or are regulated by an inflammatory stimulus, the bacterial product lipopolysaccharide (LPS).

Results: Several members of the P2RY family had striking expression patterns in macrophages; P2ry6 mRNA was essentially expressed in a macrophage-specific fashion, whilst P2ry1 and P2ry5 mRNA levels were strongly down-regulated by LPS. Expression of several other GPCRs was either restricted to macrophages (e.g. Gpr84) or to both macrophages and neural tissues (e.g. P2ry12, Gpr85). The GPCR repertoire expressed by bone marrow-derived macrophages and thioglycollate-elicited peritoneal macrophages had some commonality, but there were also several GPCRs preferentially expressed by either cell population.

Conclusion: The constitutive or regulated expression in macrophages of several GPCRs identified in this study has not previously been described. Future studies on such GPCRs and their agonists are likely to provide important insights into macrophage biology, as well as novel inflammatory pathways that could be future targets for drug discovery.

No MeSH data available.


Macrophage-restricted GPCRs. Micro-array analysis of Gpr85 (A), P2ry6 (B) and Gpr84 (C) mRNA expression across a panel of 91 murine cell types and tissues. Data points show normalised values and similar cell types are grouped according to bar colour; blue indicates primary macrophage cell types, purple indicates bone-related cell types, red indicates other immune cell types, green indicates stem cell populations, orange indicates whole tissue samples, yellow indicates neuronal and retinal cell types and pink indicates cell lines. Additional file 3 gives details of the 91 cell types and tissues profiled.
© Copyright Policy - open-access
Related In: Results  -  Collection

License
getmorefigures.php?uid=PMC2394514&req=5

Figure 1: Macrophage-restricted GPCRs. Micro-array analysis of Gpr85 (A), P2ry6 (B) and Gpr84 (C) mRNA expression across a panel of 91 murine cell types and tissues. Data points show normalised values and similar cell types are grouped according to bar colour; blue indicates primary macrophage cell types, purple indicates bone-related cell types, red indicates other immune cell types, green indicates stem cell populations, orange indicates whole tissue samples, yellow indicates neuronal and retinal cell types and pink indicates cell lines. Additional file 3 gives details of the 91 cell types and tissues profiled.

Mentions: In order to identify GPCRs that were very highly expressed by BMM and/or TEPM, we set an arbitrary cut-off in which normalised expression in either BMM or TEPM was at least 10-fold greater than the median normalised expression across all cell types. Using this very strict filtering approach, we identified 33 GPCRs that were enriched in BMM and/or TEPM as compared to the median normalised expression (Table 1 and 2). This, of course, does not mean that such genes are exclusively expressed by macrophages. For example, Gpr85 was highly expressed in several macrophage populations and was further up-regulated by LPS, but was also expressed in several regions of the brain (Figure 1a). Nevertheless, included in this set were GPCRs such as Emr1 (F4/80), C3aR, C5aR, Ccrl2 and Ccr2 that are known to be either macrophage-specific or highly expressed by macrophages [8-12], thus validating our approach. Also included in this list were a number of GPCRs (e.g. Edg5, P2ry2 and 6) that have not previously been reported to have a macrophage-restricted expression pattern (Table 2). As demonstrated in figure 1b, P2ry6 expression was strikingly restricted to macrophages and two cell types closely related to macrophages (osteoclasts and dendritic cells), whilst a number of other P2Y family receptors were also highly expressed by this lineage (Table 2). Consistent with this conclusion, we recently observed a macrophage-restricted expression pattern for P2ry6 mRNA in a much more limited analysis across seven different cell populations [2]. Gpr84 expression was also largely restricted to macrophage populations and granulocytes (Figure 1c).


Expression analysis of G Protein-Coupled Receptors in mouse macrophages.

Lattin JE, Schroder K, Su AI, Walker JR, Zhang J, Wiltshire T, Saijo K, Glass CK, Hume DA, Kellie S, Sweet MJ - Immunome Res (2008)

Macrophage-restricted GPCRs. Micro-array analysis of Gpr85 (A), P2ry6 (B) and Gpr84 (C) mRNA expression across a panel of 91 murine cell types and tissues. Data points show normalised values and similar cell types are grouped according to bar colour; blue indicates primary macrophage cell types, purple indicates bone-related cell types, red indicates other immune cell types, green indicates stem cell populations, orange indicates whole tissue samples, yellow indicates neuronal and retinal cell types and pink indicates cell lines. Additional file 3 gives details of the 91 cell types and tissues profiled.
© Copyright Policy - open-access
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC2394514&req=5

Figure 1: Macrophage-restricted GPCRs. Micro-array analysis of Gpr85 (A), P2ry6 (B) and Gpr84 (C) mRNA expression across a panel of 91 murine cell types and tissues. Data points show normalised values and similar cell types are grouped according to bar colour; blue indicates primary macrophage cell types, purple indicates bone-related cell types, red indicates other immune cell types, green indicates stem cell populations, orange indicates whole tissue samples, yellow indicates neuronal and retinal cell types and pink indicates cell lines. Additional file 3 gives details of the 91 cell types and tissues profiled.
Mentions: In order to identify GPCRs that were very highly expressed by BMM and/or TEPM, we set an arbitrary cut-off in which normalised expression in either BMM or TEPM was at least 10-fold greater than the median normalised expression across all cell types. Using this very strict filtering approach, we identified 33 GPCRs that were enriched in BMM and/or TEPM as compared to the median normalised expression (Table 1 and 2). This, of course, does not mean that such genes are exclusively expressed by macrophages. For example, Gpr85 was highly expressed in several macrophage populations and was further up-regulated by LPS, but was also expressed in several regions of the brain (Figure 1a). Nevertheless, included in this set were GPCRs such as Emr1 (F4/80), C3aR, C5aR, Ccrl2 and Ccr2 that are known to be either macrophage-specific or highly expressed by macrophages [8-12], thus validating our approach. Also included in this list were a number of GPCRs (e.g. Edg5, P2ry2 and 6) that have not previously been reported to have a macrophage-restricted expression pattern (Table 2). As demonstrated in figure 1b, P2ry6 expression was strikingly restricted to macrophages and two cell types closely related to macrophages (osteoclasts and dendritic cells), whilst a number of other P2Y family receptors were also highly expressed by this lineage (Table 2). Consistent with this conclusion, we recently observed a macrophage-restricted expression pattern for P2ry6 mRNA in a much more limited analysis across seven different cell populations [2]. Gpr84 expression was also largely restricted to macrophage populations and granulocytes (Figure 1c).

Bottom Line: The GPCR repertoire expressed by bone marrow-derived macrophages and thioglycollate-elicited peritoneal macrophages had some commonality, but there were also several GPCRs preferentially expressed by either cell population.The constitutive or regulated expression in macrophages of several GPCRs identified in this study has not previously been described.Future studies on such GPCRs and their agonists are likely to provide important insights into macrophage biology, as well as novel inflammatory pathways that could be future targets for drug discovery.

View Article: PubMed Central - HTML - PubMed

Affiliation: Cooperative Research Centre for Chronic Inflammatory Diseases and Special Research Centre for Functional and Applied Genomics, Institute for Molecular Bioscience, University of Queensland, Brisbane, Queensland, 4072, Australia. j.lattin@imb.uq.edu.au

ABSTRACT

Background: Monocytes and macrophages express an extensive repertoire of G Protein-Coupled Receptors (GPCRs) that regulate inflammation and immunity. In this study we performed a systematic micro-array analysis of GPCR expression in primary mouse macrophages to identify family members that are either enriched in macrophages compared to a panel of other cell types, or are regulated by an inflammatory stimulus, the bacterial product lipopolysaccharide (LPS).

Results: Several members of the P2RY family had striking expression patterns in macrophages; P2ry6 mRNA was essentially expressed in a macrophage-specific fashion, whilst P2ry1 and P2ry5 mRNA levels were strongly down-regulated by LPS. Expression of several other GPCRs was either restricted to macrophages (e.g. Gpr84) or to both macrophages and neural tissues (e.g. P2ry12, Gpr85). The GPCR repertoire expressed by bone marrow-derived macrophages and thioglycollate-elicited peritoneal macrophages had some commonality, but there were also several GPCRs preferentially expressed by either cell population.

Conclusion: The constitutive or regulated expression in macrophages of several GPCRs identified in this study has not previously been described. Future studies on such GPCRs and their agonists are likely to provide important insights into macrophage biology, as well as novel inflammatory pathways that could be future targets for drug discovery.

No MeSH data available.