Limits...
Interleukin-33 contributes to both M1 and M2 chemokine marker expression in human macrophages.

Joshi AD, Oak SR, Hartigan AJ, Finn WG, Kunkel SL, Duffy KE, Das A, Hogaboam CM - BMC Immunol. (2010)

Bottom Line: Human macrophages constitutively expressed the membrane-associated (i.e. ST2L) and the soluble (i.e. sST2) ST2 receptors.M2 (IL-4 + IL-13) skewing stimuli markedly increased the expression of ST2L, but neither polarizing cytokine treatment promoted the release of sST2 from these cells.Together, these data suggest that primary responses to IL-33 in bone marrow derived human macrophages favors M1 chemokine generation while its addition to polarized human macrophages promotes or amplifies M2 chemokine expression.

View Article: PubMed Central - HTML - PubMed

Affiliation: Department of Pathology, University of Michigan Medical School, Ann Arbor, MI, USA.

ABSTRACT

Background: Interleukin-33 is a member of the IL-1 cytokine family whose functions are mediated and modulated by the ST2 receptor. IL-33-ST2 expression and interactions have been explored in mouse macrophages but little is known about the effect of IL-33 on human macrophages. The expression of ST2 transcript and protein levels, and IL-33-mediated effects on M1 (i.e. classical activation) and M2 (i.e. alternative activation) chemokine marker expression in human bone marrow-derived macrophages were examined.

Results: Human macrophages constitutively expressed the membrane-associated (i.e. ST2L) and the soluble (i.e. sST2) ST2 receptors. M2 (IL-4 + IL-13) skewing stimuli markedly increased the expression of ST2L, but neither polarizing cytokine treatment promoted the release of sST2 from these cells. When added to naïve macrophages alone, IL-33 directly enhanced the expression of CCL3. In combination with LPS, IL-33 blocked the expression of the M2 chemokine marker CCL18, but did not alter CCL3 expression in these naive cells. The addition of IL-33 to M1 macrophages markedly increased the expression of CCL18 above that detected in untreated M1 macrophages. Similarly, alternatively activated human macrophages treated with IL-33 exhibited enhanced expression of CCL18 and the M2 marker mannose receptor above that detected in M2 macrophages alone.

Conclusions: Together, these data suggest that primary responses to IL-33 in bone marrow derived human macrophages favors M1 chemokine generation while its addition to polarized human macrophages promotes or amplifies M2 chemokine expression.

Show MeSH

Related in: MedlinePlus

M1 and M2 polarizing conditions in cultured human bone marrow-derived macrophages promote the expression of either M1- or M2-specific transcripts, respectively. (A) Representative flow cytometric analysis of primary human macrophages derived from bone marrow. Cells were stained using anti-CD11b, anti-CD14, anti-CD163, or anti-CD68 antibodies. (B) Human macrophages stimulated with IFN-γ +LPS (i.e. M1 condition) or (C) IL-4+IL-13 (i.e. M2 condition) and gene expression was analyzed 24 h later by TAQMAN. Transcript levels for each M1 and M2 factor are expressed as fold increase over transcript levels of these factors in human macrophages exposed to media alone (i.e. control condition). Each symbol represents a single donor and macrophages from 5 to 8 bone marrow donors were analyzed; mean and SEM are also shown in panels B and C. * P ≤ 0.05 compared with transcript levels in control macrophages; ** P ≤ 0.01 compared with transcript levels in control macrophages.
© Copyright Policy - open-access
Related In: Results  -  Collection

License
getmorefigures.php?uid=PMC2967528&req=5

Figure 1: M1 and M2 polarizing conditions in cultured human bone marrow-derived macrophages promote the expression of either M1- or M2-specific transcripts, respectively. (A) Representative flow cytometric analysis of primary human macrophages derived from bone marrow. Cells were stained using anti-CD11b, anti-CD14, anti-CD163, or anti-CD68 antibodies. (B) Human macrophages stimulated with IFN-γ +LPS (i.e. M1 condition) or (C) IL-4+IL-13 (i.e. M2 condition) and gene expression was analyzed 24 h later by TAQMAN. Transcript levels for each M1 and M2 factor are expressed as fold increase over transcript levels of these factors in human macrophages exposed to media alone (i.e. control condition). Each symbol represents a single donor and macrophages from 5 to 8 bone marrow donors were analyzed; mean and SEM are also shown in panels B and C. * P ≤ 0.05 compared with transcript levels in control macrophages; ** P ≤ 0.01 compared with transcript levels in control macrophages.

Mentions: Flow cytometric analysis of human bone marrow-derived macrophages revealed that the culture techniques employed promoted the expression of CD11b, CD68, and CD163 on approximately 90% of these cells (Figure 1A). CD14 was also expressed by approximately 40% of the cultured macrophages. Cultures of human macrophages were skewed toward a M1 phenotype upon exposure to IFN-γ and LPS for 24 h (Figure 1B). This was apparent by the elevated transcript levels of the M1 markers CCR7 and CCL3 in these cells (Figure 1B). The fold-increase in CCL3 transcript levels in M1 macrophages reached statistical significance compared with untreated or control macrophages (Figure 1B). Conversely, transcripts for two human M2 markers CCL18 and mannose receptor [5], but not the M1 markers CCR7 or CCL3 [5], were significantly elevated under M2 conditions compared with control macrophages (Figure 1C). Thus, with the appropriate external stimuli, human macrophages appeared to predominately express either M1 or M2 chemokine markers.


Interleukin-33 contributes to both M1 and M2 chemokine marker expression in human macrophages.

Joshi AD, Oak SR, Hartigan AJ, Finn WG, Kunkel SL, Duffy KE, Das A, Hogaboam CM - BMC Immunol. (2010)

M1 and M2 polarizing conditions in cultured human bone marrow-derived macrophages promote the expression of either M1- or M2-specific transcripts, respectively. (A) Representative flow cytometric analysis of primary human macrophages derived from bone marrow. Cells were stained using anti-CD11b, anti-CD14, anti-CD163, or anti-CD68 antibodies. (B) Human macrophages stimulated with IFN-γ +LPS (i.e. M1 condition) or (C) IL-4+IL-13 (i.e. M2 condition) and gene expression was analyzed 24 h later by TAQMAN. Transcript levels for each M1 and M2 factor are expressed as fold increase over transcript levels of these factors in human macrophages exposed to media alone (i.e. control condition). Each symbol represents a single donor and macrophages from 5 to 8 bone marrow donors were analyzed; mean and SEM are also shown in panels B and C. * P ≤ 0.05 compared with transcript levels in control macrophages; ** P ≤ 0.01 compared with transcript levels in control macrophages.
© Copyright Policy - open-access
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC2967528&req=5

Figure 1: M1 and M2 polarizing conditions in cultured human bone marrow-derived macrophages promote the expression of either M1- or M2-specific transcripts, respectively. (A) Representative flow cytometric analysis of primary human macrophages derived from bone marrow. Cells were stained using anti-CD11b, anti-CD14, anti-CD163, or anti-CD68 antibodies. (B) Human macrophages stimulated with IFN-γ +LPS (i.e. M1 condition) or (C) IL-4+IL-13 (i.e. M2 condition) and gene expression was analyzed 24 h later by TAQMAN. Transcript levels for each M1 and M2 factor are expressed as fold increase over transcript levels of these factors in human macrophages exposed to media alone (i.e. control condition). Each symbol represents a single donor and macrophages from 5 to 8 bone marrow donors were analyzed; mean and SEM are also shown in panels B and C. * P ≤ 0.05 compared with transcript levels in control macrophages; ** P ≤ 0.01 compared with transcript levels in control macrophages.
Mentions: Flow cytometric analysis of human bone marrow-derived macrophages revealed that the culture techniques employed promoted the expression of CD11b, CD68, and CD163 on approximately 90% of these cells (Figure 1A). CD14 was also expressed by approximately 40% of the cultured macrophages. Cultures of human macrophages were skewed toward a M1 phenotype upon exposure to IFN-γ and LPS for 24 h (Figure 1B). This was apparent by the elevated transcript levels of the M1 markers CCR7 and CCL3 in these cells (Figure 1B). The fold-increase in CCL3 transcript levels in M1 macrophages reached statistical significance compared with untreated or control macrophages (Figure 1B). Conversely, transcripts for two human M2 markers CCL18 and mannose receptor [5], but not the M1 markers CCR7 or CCL3 [5], were significantly elevated under M2 conditions compared with control macrophages (Figure 1C). Thus, with the appropriate external stimuli, human macrophages appeared to predominately express either M1 or M2 chemokine markers.

Bottom Line: Human macrophages constitutively expressed the membrane-associated (i.e. ST2L) and the soluble (i.e. sST2) ST2 receptors.M2 (IL-4 + IL-13) skewing stimuli markedly increased the expression of ST2L, but neither polarizing cytokine treatment promoted the release of sST2 from these cells.Together, these data suggest that primary responses to IL-33 in bone marrow derived human macrophages favors M1 chemokine generation while its addition to polarized human macrophages promotes or amplifies M2 chemokine expression.

View Article: PubMed Central - HTML - PubMed

Affiliation: Department of Pathology, University of Michigan Medical School, Ann Arbor, MI, USA.

ABSTRACT

Background: Interleukin-33 is a member of the IL-1 cytokine family whose functions are mediated and modulated by the ST2 receptor. IL-33-ST2 expression and interactions have been explored in mouse macrophages but little is known about the effect of IL-33 on human macrophages. The expression of ST2 transcript and protein levels, and IL-33-mediated effects on M1 (i.e. classical activation) and M2 (i.e. alternative activation) chemokine marker expression in human bone marrow-derived macrophages were examined.

Results: Human macrophages constitutively expressed the membrane-associated (i.e. ST2L) and the soluble (i.e. sST2) ST2 receptors. M2 (IL-4 + IL-13) skewing stimuli markedly increased the expression of ST2L, but neither polarizing cytokine treatment promoted the release of sST2 from these cells. When added to naïve macrophages alone, IL-33 directly enhanced the expression of CCL3. In combination with LPS, IL-33 blocked the expression of the M2 chemokine marker CCL18, but did not alter CCL3 expression in these naive cells. The addition of IL-33 to M1 macrophages markedly increased the expression of CCL18 above that detected in untreated M1 macrophages. Similarly, alternatively activated human macrophages treated with IL-33 exhibited enhanced expression of CCL18 and the M2 marker mannose receptor above that detected in M2 macrophages alone.

Conclusions: Together, these data suggest that primary responses to IL-33 in bone marrow derived human macrophages favors M1 chemokine generation while its addition to polarized human macrophages promotes or amplifies M2 chemokine expression.

Show MeSH
Related in: MedlinePlus