Polysaccharides are significant subjects of research across various fields, including the food industry, life sciences, medical research, and materials science. Their diverse bioactivities, such as antitumor and antiviral effects and the regulation of blood glucose and lipid levels, have garnered substantial interest. As a major component of Chinese Medicine decoction, polysaccharides, being safe and effective, show great medicinal potential. However, the development of new polysaccharide-based medicinals has been limited. One major challenge is their poor oral bioavailability, coupled with a limited understanding of how polysaccharides affect cells following oral administration. Consequently, the medicinal potential of polysaccharides is often questioned, hindering research and development in this area.

Between 2014 and 2023, in the field of Chinese Medicine, there were approximately 3,400 research outputs related to polysaccharides.^[1] Research output increased rapidly year over year, and the citation impact remained consistently high, showcasing a growing interest and recognition of the significance of polysaccharides in this field.

The research^[2] conducted by Professor Han Quanbin’s team from Hong Kong Baptist University identified a hyperbranched heteroglycan isolated from huangqi, named RAP. RAP enters Peyer’s patches (the primary intestinal organs in charge of antigen uptake from the intestinal luminal surface and their transport to immune cells) via M-cell transport, and, remaining intact, activates dendritic cells (DCs) to trigger immune responses within one hour after oral administration. RAP may be further transported by DCs to tumour tissues, where it induces polarisation of antitumor macrophages, and to bone marrow, where it protects cells from the cytotoxicity of chemotherapy. Importantly, this route has also been validated in human subjects.

Previous studies have explored M cell-mediated translocation of various antigens and particles, such as the uptake of FimH (+) bacteria and yeast cell walls, leading to the use of bioengineered yeast cell wall microparticles for M cell-targeted lymphatic drug delivery.^[3],^[4] However, there is little evidence for lymphatic absorption of orally administered polysaccharides. This research bridges the gap between in vitro and in vivo studies of polysaccharides, potentially revitalising interest in the research and development of polysaccharide-based medications. The findings highlight the potential of certain polysaccharides, such as RAP, as effective carriers for lymphatic medication systems.

This is particularly relevant for the development of lymphatic medications, e.g. oral vaccines, where there is a need for M cell-targeted delivery materials. RAP demonstrates promise by protecting antigens from the harsh conditions of the gastrointestinal tract, specifically targeting M cells for effective delivery and enhancing immune responses. These properties could also be applied in the treatment of lymphatic disorders, such as cancer metastasis and lymphedema.

By offering a reliable carrier that can enhance the efficacy of vaccines and therapeutics, the research conducted by Prof. Han’s team can lead to improved public health outcomes and greater resilience against epidemics, which may stimulate new business ventures and lead to the research, development, and commercialisation of polysaccharide-rich products. This could foster economic growth within the pharmaceutical and Chinese Medicine industries, encouraging cross-regional collaboration and integration between industry, academia, and research.

Additionally, since polysaccharides are a dominant component in Chinese Medicine decoctions, the findings provide valuable insights into the mechanisms of action of Chinese Medicinal and could further inspire innovations within the Chinese Medicine field. By demonstrating the scientific validity and potential health benefits of Chinese Medicine, this research could enhance its acceptance and integration into mainstream healthcare systems.

[1] Research output mentioned “polysaccharide” in title, abstract or keywords.

[2] Zhang, Quanwei, et al. “M Cells of Mouse and Human Peyer’s Patches Mediate the Lymphatic Absorption of an Astragalus Hyperbranched Heteroglycan.” Carbohydrate Polymers, vol. 296, Elsevier BV, Nov. 2022, pp. 119952–52, https://doi.org/10.1016/j.carbpol.2022.119952.

[3] Sakhon, Olivia S., et al. “M Cell-Derived Vesicles Suggest a Unique Pathway for Trans-Epithelial Antigen Delivery.” Tissue Barriers, vol. 3, no. 1-2, Informa UK Limited, Feb. 2015, p. e1004975, https://doi.org/10.1080/21688370.2015.1004975. Accessed 21 Apr. 2025.

[4] Hase, Koji, et al. “Uptake through Glycoprotein 2 of FimH+ Bacteria by M Cells Initiates Mucosal Immune Response.” Nature, vol. 462, no. 7270, Nov. 2009, pp. 226–30, https://doi.org/10.1038/nature08529.