Activation of macrophages by polysaccharide–protein complex from Lycium barbarum L.

Abstract

Macrophages play crucial roles in innate immunity. This paper reports that a polysaccharide-protein complex isolated from Lycium barbarum (LBP) is able to activate macrophages. LBP was isolated from Lycium barbarum fruit and separated to five homogenous fractions, designated LBPF1, LBPF2, LBPF3, LBPF4 and LBPF5. It was found that LBP (50 mg/kg, i.p.) markedly upregulated the expressions of CD40, CD80, CD86 and MHC class II molecules on peritoneal macrophages. In vitro studies showed that LBP and LBPF1-5 activated transcription factors NF-kappaB and AP-1 by RAW264.7 macrophage cells, induced TNF-alpha, IL-1beta, IL-12p40 mRNA expression, and enhanced TNF-alpha production in a dose-dependent manner. Furthermore, LBP (50 mg/kg, i.p.) significantly enhanced macrophage endocytic and phagocytic capacities in vivo. These results indicate that LBP enhances innate immunity by activating macrophages. The mechanism may be through activation of transcription factors NF-kappaB and AP-1 to induce TNF-alpha production and upregulation of MHC class II costimulatory molecules.

Effects of Lycium barbarum polysaccharides with different molecular weights on function of RAW264.7 macrophages

“…These molecules not only are activation markers but also can enhance the ability of macrophages to present antigens to T cells (Mosser & Edwards, 2008). Previous studies had reported that LBP and its polysaccharide-protein complex could enhance the expression levels of MHC-II and CD86 molecules on acrophages in vivo and in vitro (Chen et al, 2009;Zhang et al, 2011). In the present study, the results showed that LBP fractions with different MW and LPS could enhance the expression levels of MHC-II and CD86 molecules on RAW264.7 macrophages significantly (Figure 1).…”

“…These cytokines and chemokines play an important role in inducing inflammation response which can also attracts neutrophils, lymphocytes, dendritic cells and monocytes to the pathogen infection site. Previous studies had reported that LBP could enhance the secretion of TNF-α, IL-12 p40 and IL-1β in murine macrophages (Chen et al, 2009;Zhang et al, 2011). In the present study, we investigated the effects of LBP fractions with different MW on the TNF-α and IL-6 secretion in RAW264.7 macrophages.…”

“…Lycium barbarum polysaccharides (LBP) which are extracted from the edible fruit of Chinese herb Lycium barbarum have the ability to activate macrophages. LBP could upregulate the expressions of CD40, CD80, CD86 and MHC class II molecules, and enhance phagocytosis in murine peritoneal macrophages (Chen, Soo, Srinivasan, Tan, & Chan, 2009). Polysaccharide-protein complex (LBPF4) from Lycium barbarum L. and LBPF4-OL which were the glycan part of LBPF4 both could significantly induce TNF-α, IL-1β and NO production on macrophage, and enhance macrophage phagocytosis (Zhang, Li, et al, 2014).…”

Lycium Barbarum and Human Health

“…The protein contents were 1. A polysaccharide-protein complex isolated from L. barbarum can also enhance innate immunity by activating macrophages (Chen et al 2009b). Research has found that LBPF1-5 can activate T lymphocytes and enhance the Th1 response, and polysaccharide-protein complex-treated DCs displayed enhanced Th1 and Th2 responses in vitro and in vivo (Chen et al 2008b(Chen et al , 2009a.…”

“…The mechanism may be mediated via activation of transcription factors NF-κB and AP-1 to induce production of TNF-α and upregulation of MHC class II (Chen et al 2009b). markedly upregulated the expressions of CD40, CD80, CD86, and MHC class II molecules on peritoneal macrophages.…”