Skip to content


Immuno Stimulation

computer generated representation of LickM cells

Our patented lichenase booster molecule, LickM, is a modified thermostable variant of the lichenase protein from the thermophilic bacterium Clostridium thermocellum. LicKM may be effective in addressing issues with subunit vaccines which, while having a track record in protecting humans against deadly diseases, may be insufficiently stable and require the use of a strong adjuvant to boost their immunogenicity.

Additionally, our patented LicKM protein fusions have been shown to be more soluble and expressed at higher levels than antigens alone.1 The protein itself may confer its thermostability onto fusion proteins, allowing for easy and cost-effective recovery of target proteins following heat treatment.With three available insertion sites (N-terminus, C-terminus, and internal loop), LicKM allows the integration of three antigens (or multiple copies of the same antigen) within a single stable fusion protein as well as identification of the optimal insertion location.3

Advantages of IBio’s LicKM-Antigen Fusions

  • Increased Solubility
  • Increased Expression
  • Ease of Purification
  • Demonstrated effectiveness
  • Demonstrated safety (IBIO-201 IND enabling safety study)
  • Multiple antigen cloning sites
  • Robust immune response
  • Long-lasting immunity

Development Status

Previously published peer-reviewed laboratory data demonstrated an iBio lichenase-based vaccine provided full-protection against aerosolized pneumonic plague in non-human primates.3

Published data have demonstrated the value of the lichenase technology in vaccine candidates targeting both anthrax and yellow fever virus.3,5

IBIO-201, our vaccine candidate combining antigens derived from the spike (S) protein fused with LicKM™, recently completed IND-enabling toxicology studies. The studies identified no adverse effects at low or high doses.

a person working in biotechnology using a microscope in a laboratory environment
  1. Massa S., et al. (2007) Anti-cancer activity of plant-produced HPV16 E7 vaccine. Vaccine25, 3018-3021
  2. Piruzian E.S., et al. (1998) The use of a thermostable β-glucanase gene from Clostridium thermocellum as a reporter gene in plants.  Genet., 257: 561-567
  3. Tottey S., et al. (2018) Plant-Produced Subunit Vaccine Candidates against Yellow Fever Induce Virus Neutralizing Antibodies and Confer Protection against Viral Challenge in Animal Models.  Trop. Med. Hyg. 98, p. 420–431
  4. Chichester, J., et al. (2009) A single component two-valent LcrV-F1 vaccine protects non-human primates against pneumonic plague. Vaccine27, 3471-3474
  5. Chichester, J. et al (2007) Immunogenicity of a subunit vaccine against Bacillus anthracis. Vaccine25, 3111-3114