A novel phycobiliprotein alleviates allergic airway inflammation by modulating immune responses.

Abstract

RATIONALE:

it has been claimed that phycocyanin exhibits pharmaceutical functions in inhibiting histamine release and leukotriene biosynthesis. In allergic asthma, these inflammatory mediators are crucial for disease progression.

OBJECTIVES:

the aim of this study was to evaluate the therapeutic potential of R-phycocyanin (R-PC) against allergic airway inflammation.

METHODS:

mouse bone marrow-derived dendritic cells (BMDCs) were used to evaluate the immunomodulatory functions of R-PC. In addition, an airway inflammatory model was used to evaluate the therapeutic potential of R-PC.

MEASUREMENTS AND MAIN RESULTS:

R-PC treatment resulted in a decrease of endocytosis, increase of costimulatory molecule expression, and enhancement of interleukin-12 production in mouse BMDCs. Moreover, R-PC-treated cultured dendritic cells were able to promote CD4(+) T-cell stimulatory capacity and increase interferon-γ expression in CD4(+) T cells. Intraperitoneal administration of R-PC suppressed ovalbumin (OVA)-induced airway hyperresponsiveness, serum levels of OVA-specific IgE and IgG1, eosinophil infiltration, Th2 cytokine levels, and eotaxin in bronchoalveolar lavage fluid of mice. Antibody against Toll-like receptor-4 was able to inhibit R-PC-induced IL-12 p70 production. Moreover, inhibition of nuclear factor-κB (NF-κB) by helenalin and inhibition of the JNK pathway by JNK inhibitor II inhibited R-PC-induced IL-12 p70 production. Western blotting and electrophoretic mobility shift assays showed that R-PC augmented phosphorylation of the inhibitors of NF-κB and inhibitors of NF-κB kinase and facilitated NF-κB activity.

CONCLUSIONS:

our data demonstrated that R-PC promoted activation and maturation of cultured dendritic cells and skewed the immunological function toward Th1 activity. Therefore, R-PC may have potential in regulating immune responses and application in reducing allergic asthma.

• Authors: Chun-Jung Chang, Yao-Hsu Yang, Yu-Chih Liang, Chiao-Juno Chiu, Kuan-Hua Chu, Hung-Non Chou, Bor-Luen Chiang
• Journal: American journal of respiratory and critical care medicine (Am J Respir Crit Care Med) Vol. 183 Issue 1 Pg. 15-25 (Jan 01 2011) ISSN: 1535-4970 [Electronic] United States
• PMID: 20709826 (Publication Type: Journal Article)

Chemical References

• Leukotrienes
• Phycobiliproteins

Topics

• Animals
• Asthma (drug therapy, immunology, metabolism)
• Blotting, Western
• Disease Models, Animal
• Disease Progression
• Female
• Histamine Release (drug effects)
• Immunity, Innate
• Inflammation (immunology, metabolism, prevention & control)
• Leukotrienes (biosynthesis)
• Mice
• Mice, Inbred BALB C
• Phycobiliproteins (pharmacology)