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. 2012 Aug;47(2):196-202.
doi: 10.1165/rcmb.2011-0294OC. Epub 2012 Mar 15.

Syndecan-4 regulates early neutrophil migration and pulmonary inflammation in response to lipopolysaccharide

Yoshinori Tanino  1 , Mary Y Chang, Xintao Wang, Sean E Gill, Shawn Skerrett, John K McGuire, Suguru Sato, Takefumi Nikaido, Tetsuhito Kojima, Mitsuru Munakata, Steve Mongovin, William C Parks, Thomas R Martin, Thomas N Wight, Charles W Frevert
Affiliations

Syndecan-4 regulates early neutrophil migration and pulmonary inflammation in response to lipopolysaccharide

Yoshinori Tanino et al. Am J Respir Cell Mol Biol. 2012 Aug.

Abstract

Proteoglycans (PGs) and their associated glycosaminoglycan side chains are effectors of inflammation, but little is known about changes to the composition of PGs in response to lung infection or injury. The goals of this study were to identify changes to heparan sulfate PGs in a mouse model of gram-negative pneumonia, to identify the Toll-like receptor adaptor molecules responsible for these changes, and to determine the role of the heparan sulfate PG in the innate immune response in the lungs. We treated mice with intratracheal LPS, a component of the cell wall of gram-negative bacteria, to model gram-negative pneumonia. Mice treated with intratracheal LPS had a rapid and selective increase in syndecan-4 mRNA that was regulated through MyD88-dependent mechanisms, whereas expression of several other PGs was not affected. To determine the role of syndecan-4 in the inflammatory response, we exposed mice deficient in syndecan-4 to LPS and found a significant increase in neutrophil numbers and amounts of CXC-chemokines and total protein in bronchoalveolar lavage fluid. In studies performed in vitro, macrophages and epithelial cells treated with LPS had increased expression of syndecan-4. Studies performed using BEAS-2B cells showed that pretreatment with heparin and syndecan-4 decreased the expression of CXCL8 mRNA in response to LPS and TNF-α. These findings indicate that the early inflammatory response to LPS involves marked up-regulation of syndecan-4, which functions to limit the extent of pulmonary inflammation and lung injury.

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Figures

Figure 1.
Figure 1.
Changes in the relative amounts of mRNA for the heparan sulfate proteoglycans syndecan-1, -2, and -4 and perlecan, were determined using mRNA collected from whole lung homogenates and quantitative real-time PCR. Comparison of mRNA recovered from lungs of mice treated with PBS (open symbols) and LPS (closed symbols) were made at 2, 6, and 24 hours (A). Expression of syndecan-4 in whole lung homogenates collected from C57BL/6 (WT), MyD88 knockout (MyD88 KO), and Trif mutant mice (Trif mut) treated with PBS (open bars) or LPS (closed bars) for 2 hours (B). Values are the mean ± SEM with a minimum n = 3 for each group studied. The expression of mRNA for each proteoglycan studied is expressed as a relative fold increase in mRNA over the 0-hour control group. *Groups that are significantly different (P ≤ 0.05) when mice treated with PBS and LPS were compared. The Mann-Whitney U-test was used for comparisons between the two treatment groups (A) and the Kruskal-Wallis test with Dunn's multiple comparison test was performed when multiple comparisons were made (B).
Figure 2.
Figure 2.
The total number of neutrophils recovered in bronchoalveolar lavage fluid collected from wild-type and syndecan-4 knockout (Sdc4−/−) mice treated with LPS (1 μg/g) and followed for 3 hours (A) and 6 hours (B) was determined. Values are the mean ± SEM with n = 8 to 10 mice per group for the 3-hour study and n = 11 mice per group for the 6-hour study. The y axis differs on the graphs displaying the results for the 3- and 6-hour studies. *Significantly different using the Mann-Whitney U test and a P ≤ 0.05.
Figure 3.
Figure 3.
The amount of two neutrophil chemotactic factors, KC (A) and MIP-2 (B), was measured in the bronchoalveolar lavage fluid collected from wild-type and syndecan-4 knockout (Sdc4−/−) mice treated with LPS (1 μg/g) and followed for 6 hours. Values are the mean ± SEM with n = 8 to 10 mice per group for the 3-hour study and n = 11 mice per group for the 6-hour study. *Significantly different using the Mann-Whitney U test and (P ≤ 0.05).
Figure 4.
Figure 4.
The amount of total protein in the bronchoalveolar lavage fluid collected from wild-type and syndecan-4 knockout (Sdc4−/−) mice treated with LPS (1 μg/g) was measured at 6 hours. Values are the mean ± SEM with n = 11 mice per group. *Significantly different using the Mann-Whitney's U test and (P ≤ 0.05).
Figure 5.
Figure 5.
(A) Quantitative real-time PCR showing the relative expression for syndecan-4 mRNA collected from bone marrow–derived macrophages (BMDMs) treated in vitro with RPMI media (control), two concentrations of the M1 agonist LPS (10 and 100 ng/ml), the M2a agonists IL-4/IL-13 (10 ng/ml), or the M2c agonist IL-10 for up to 48 hours (n = 4–13). (B) Quantitative real-time PCR showing the relative expression for syndecan-4 mRNA collected from alveolar macrophages treated with RPMI media (control) or LPS (100 ng/ml) for 4 hours (n = 4). (C and D) A representative histogram (C) and the geometric mean of syndecan-4 expression (D) on BMDMs measured with flow cytometry. Flow cytometry was performed 3 hours after the treatment of mouse BMDMs with RPMI or LPS (10 ng/ml) (n = 3). Values are the mean ± SEM. *Groups different from the control mice (P ≤ 0.05) using the Kruskal-Wallis test with Dunn's multiple comparison test (A) and the Mann-Whitney U test (B and D).
Figure 6.
Figure 6.
Quantitative real time PCR showing the relative expression for syndecan-4 mRNA collected from murine tracheal air–liquid interface cell cultures treated with LPS at 10 and 100 ng/ml (A) and BEAS-2B cells treated with LPS at 1,000 ng/ml (B) for the specified times. For all cultures, n = 3; for BEAS-2B cells, n = 4. Values are the mean ± SEM. *Groups different from the controls using the Kruskal-Wallis test with Dunn's multiple comparison test with P ≤ 0.05.
Figure 7.
Figure 7.
(A and B) Pretreatment of BEAS-2B cells with RPMI media or low-molecular-weight heparin (LMWH) (10 μg/ml) for 1 hour followed by treatment with media, LPS (A), or TNF-α (B) for 3 hours. (C) Pretreatment of BEAS-2B cells with RPMI media or syndecan-4 (2.5 μg/ml) for 1 hour followed by treatment with media or TNF-α for 3 hours. Values are the mean ± SEM with n = 6. An (a) shows groups that are different from the control group, and a (b) shows differences between LPS or TNF-α treatment groups using the Kruskal-Wallis test with Dunn's multiple comparison test with P ≤ 0.05.
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References

    1. Mizgerd JP. Acute lower respiratory tract infection. N Engl J Med 2008;358:716–727 - PMC - PubMed
    1. Kawai T, Akira S. The role of pattern-recognition receptors in innate immunity: update on Toll-like receptors. Nat Immunol 2010;11:373–384 - PubMed
    1. Takeuchi O, Akira S. Pattern recognition receptors and inflammation. Cell 2010;140:805–820 - PubMed
    1. Matute-Bello G, Frevert CW, Martin TR. Animal models of acute lung injury. Am J Physiol Lung Cell Mol Physiol 2008;295:L379–L399 - PMC - PubMed
    1. Jeyaseelan S, Chu HW, Young SK, Freeman MW, Worthen GS. Distinct roles of pattern recognition receptors CD14 and Toll-like receptor 4 in acute lung injury. Infect Immun 2005;73:1754–1763 - PMC - PubMed

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