Science Bite (3 minute oral presentation with PPT in live session and poster) - Students, ECRs and EMCRs only 16th Lorne Infection and Immunity 2026

Galectin 3 and 9 homologues of gastrointestinal soil transmitted helminths and the search for anti-inflammatory molecules (132541)

Elizabeth A Mullens 1 , Gemma Zerna 2 , Rob Bischof 3 , Farah Ahmady 4 , David Piedrafita 5 , Sarah Preston 1
  1. Federation University , Mt Helen, VICTORIA, Australia
  2. Latrobe University Australia, Bundoora, Victoria, Australia
  3. Federation University, Berwick, Victoria, Australia
  4. Fiona Elsey Cancer Research Institute, Ballarat, Victoria, Australia
  5. Federation University, Churchill, Victoria, Australia

The search for novel treatments for chronic inflammatory conditions has led to an increased interest in gastrointestinal nematodes and the molecules they produce to evade the human immune system. Galectins are carbohydrate-binding proteins that are potent, multifunctional signalling proteins for the immune system, and form a large component of the excretory/secretory molecules nematodes produce during infection.

The aim of this research was to determine if Necator americanus (New World Hookworm) and Trichuris trichiura (Human Whipworm), produced functional galectin homologues of human galectin 3 and 9, and determine if they display immune-modulatory properties.

Protein databases for N. americanus and T. trichiura were analysed for with significant sequence and structural similarity to human galectin 3 and 9.  Four proteins were expressed using E. coli and purified by lactose affinity purification.

Recombinant hookworm-galectin-3 (rHW-gal-3) increased proliferation in the human epithelial HCA-7 colon carcinoma cell line, 20% on average at 5ug/ml, compared to untreated cells (p-value <0.05).

Flow cytometry and immunolocalisation confirmed that rHW-gal-3 bound to the surface of human PBMCs. The cytokine concentrations, of transforming growth factor-β (TGF-β), Interlukin-10 (IL-10), Interferon-γ (INF-γ), IL-4, IL-6, IL-8 and monocyte chemoattractant protien-1 (MCP-1) were significantly increased following rHW-gal-3 treatment (p-value<0.01). PBMCs treated with 0.5µg/ml of human-recombinant-galectin-3, compared to cells treated at 0.5µg/ml of rHW-gal-3, produced comparable concentrations of INF-γ, IL-4, IL-2, IL-17A, MCP-1, tumour necrosis factor-α (p-value >0.4).

In-vitro results suggest that synthetic parasitic galectin molecules may interfere with host cells and have similar functions to host galectins. PBMCs produced a significant cytokine response to rHW-gal-3, with some cytokines produced at comparable levels to human-gal-3 treated cells. This research may further our understanding of how nematodes alter the host immune system to modulate inflammation.