Maturation of dendritic cells by pullulan promotes anti-cancer effect

Abstract

Previous studies have demonstrated that pullulan, a polysaccharide purified from Aureobasidium pullulans, has immune-stimulatory effects on T and B cells. Moreover, pullulan has been used as a carrier in the delivery of the antigen (Ag) peptide to lymphoid tissues. However, the in vivo effect of pullulan on dendritic cells (DC) has not been well characterized. In this study, we assessed the effect of pullulan on DC activation and anti-cancer immunity. The results showed that the pullulan treatment up-regulated co-stimulatory molecule expression and enhanced pro-inflammatory cytokine production in bone marrow-derived DCs (BMDC) in vitro and in spleen DCs in vivo. Moreover, the combination of ovalbumin (OVA) and pullulan induced OVA antigen-specific T cell activations in vivo. In tumor-bearing mice, pullulan induced the maturation of DCs in spleen and tumor draining lymph node (drLN), and promoted the OVA-specific T cell activation and migration of the T cells into the tumor. In addition, the combination of OVA and pullulan inhibited B16-OVA tumor growth and liver metastasis. The combination of tyrosinase-related protein 2 (TRP2) peptide and pullulan treatment also suppressed B16 melanoma growth. Thus, the results demonstrated that pullulan enhanced DC maturation and function, and it acted as an adjuvant in promoting Ag-specific immune responses in mice. Thus, pullulan could be a new and useful adjuvant for use in therapeutic cancer vaccines.

A decreased peritumoral CD1a+ cell number predicts a worse prognosis in oral squamous cell carcinoma

“…The aim of DC vaccination is to induce tumour-specific effector T cells that can specifically reduce the tumour mass and that can induce immunological memory to reduce the risk of cancer recurrence. 34,35 In conclusion, our results suggest that depletion of peritumoral CD1a+ cells is a strong independent prognostic factor, predicting higher recurrence rates and lower survival outcomes. Therefore, the distribution of DCs in OSCC tumour tissues can be considered to be a good prognostication tool.…”

“…DCs are potentially good candidates for use in therapeutic cancer vaccines. The aim of DC vaccination is to induce tumour‐specific effector T cells that can specifically reduce the tumour mass and that can induce immunological memory to reduce the risk of cancer recurrence …”

Proof of concept of the preventive efficacy of high‐dose recombinant mono‐allergen immunotherapy in atopic dogs sensitized to the Dermatophagoides farinae allergen Der f 2

“…Polymers of pullulan, an alpha‐glucan with a basic unit composed of three alpha‐1,4‐linked glucose molecules (maltotriose) connected by alpha‐1,6‐linkages on the terminal glucose, are known not only to enhance the plasma half‐life of conjugated molecules, but they can also reduce their IgE recognition and hence their allergenicity . Furthermore, pullulan has been shown to exhibit immunomodulating properties that are desirable in an AIT adjuvant, for example, the promotion of secretion of pro‐inflammatory (IL‐1‐beta, IL‐6, IL‐8/CXCL8 and TNF‐alpha) and type‐1 cytokines such as IL‐23 and interferon‐alpha and ‐gamma …”

The Multiple and Versatile Roles of Aureobasidium pullulans in the Vitivinicultural Sector

“…β-glucan exhibits immune stimulatory activity, and is consumed as a supplement in many countries. Also, A. pullulans culture supernatant is believed to exhibit beneficial effects in delaying the onset of a number of diseases, and has been reported to exhibit antitumor, antiallergy and anti-infectious disease activities in mouse models [58][59][60][61][62][63][64][65][66][67][68]. An interesting review by Li et al [69] on Aureobasidium spp.…”