Galactomannan from Caesalpinia spinosa induces phenotypic and functional maturation of human dendritic cells.
Plant polysaccharides present an interesting potential as immunomodulators, particularly in the induction of antitumoral responses, principally because of their molecular complexity and low in vivo toxicity. Activation of dendritic cells (DCs) could improve antitumoral responses usually diminished in cancer patients, and natural adjuvants provide a possibility of inducing this activation. Herein, we investigated the immunomodulatory activity of a neutral plant polysaccharide Galactomannan on human monocyte-derived DCs (MDDC). MDDCs were stimulated with Galactomannan (GLM) from Caesalpinia spinosa and both phenotypic and functional activities were assessed by flow cytometry and real-time PCR. The phagocytic ability of MDDCs was determined by using E-coli pHrodo particles and induction of T-lymphocyte allostimulation was determined after T-cell staining with carboxyfluorescein succinimidyl ester (CFSE). In MDDCs, purified Galactomannan induced phenotypic maturation revealed by increased expression of CD83, CD86, CD206, and HLA-DR. Functional experiments showed the loss of particulate antigen uptake in Galactomannan-stimulated DCs and increased alloantigen presentation capacity. Finally, Galactomannan increased protein and mRNA levels of pro-inflammatory cytokines including IL-1β, IL-6, IL-8, IL-12p70, and TNF-α. These data reveal that Galactomannan obtained from Caesalpinia spinosa promotes effective activation of MDDCs. This adjuvant-like activity may have therapeutic applications in clinical settings where immune responses need boosting.
Immunology and Cellular Biology Group, Faculty of Sciences, Pontificia Universidad Javeriana Bogotá, Colombia.
S P
SP
Santander
M
M
Aoki
J F
JF
Hernandez
M
M
Pombo
H
H
Moins-Teisserenc
N
N
Mooney
S
S
Fiorentino
D000276:Adjuvants, Immunologic / Q000494:pharmacology*; D017951:Antigen Presentation / Q000187:drug effects; D000943:Antigens, Differentiation / Q000378:metabolism; D029911:Caesalpinia / Q000276:immunology; D002454:Cell Differentiation / Q000187:drug effects; D049109:Cell Proliferation; D002469:Cell Separation; D016207:Cytokines / Q000235:genetics / Q000378:metabolism*; D003713:Dendritic Cells / Q000187:drug effects* / Q000378:metabolism / Q000473:pathology; D005434:Flow Cytometry; D005690:Galactose / Q000031:analogs & derivatives; D006801:Humans; D018836:Inflammation Mediators / Q000378:metabolism*; D008213:Lymphocyte Activation / Q000187:drug effects; D007959:Lymphocyte Culture Test, Mixed; D008351:Mannans / Q000494:pharmacology*; D010587:Phagocytosis / Q000187:drug effects; D013601:T-Lymphocytes / Q000276:immunology
D000276:Adjuvants, Immunologic; D000943:Antigens, Differentiation; D016207:Cytokines; D018836:Inflammation Mediators; D008351:Mannans; C012990:galactomannan; D005690:Galactose