Loiasis, a debilitating parasitic disease caused by the filarial worm Loa loa, has long been overshadowed by other high-profile neglected tropical diseases. As a research service provider, Protheragen is at the forefront of Loiasis vaccine and therapeutics development, leveraging cutting-edge scientific research and technological advancements.
Overview of Loiasis
Loiasis (Loa loa filariasis), a neglected tropical disease, is caused by the filarial nematode Loa loa. This disease is transmitted through the bite of infected deer flies (Chrysops spp.) or mango flies, which are the vectors for Loa loa. The adult Loa loa filarial worm can reach lengths of three to seven centimeters and migrates throughout the subcutaneous tissues of humans, occasionally crossing into subconjunctival tissues of the eye where it can be easily observed. Though Loiasis does not normally affect vision, it can be painful when the worm moves across the eyeball or the bridge of the nose. The disease can also cause red, itchy swellings below the skin known as "Calabar swellings."
Fig.1 The spectrum of atypical manifestations of loiasis. (Dieki R., et al., 2022)
Vaccine Development for Loiasis
Antigen Discovery and Immunoprophylaxis
Vaccine development for Loiasis is focused on identifying key antigens that can elicit a protective immune response. The sequencing of the Loa loa genome has been a significant step forward, revealing a range of potential vaccine candidates. One such antigen is the 15-kDa gene product, which has shown to be immunogenic and allergenic in host responses. The potential vaccine targets include not only the larval stage but also the adult worm antigens to prevent maturation and establishment of the parasite within the host.
Immune Response Modulation
Another approach to vaccine development is modulating the host's immune response to prevent the establishment and progression of the infection. Understanding the immune evasion mechanisms employed by Loa loa, such as the acquisition of host regulatory proteins by microfilariae to evade complement attack, is crucial. Vaccines could be designed to enhance the host's immune system's ability to recognize and eliminate the parasite.
Therapeutics Development for Loiasis
Antifilarial Chemotherapy
The current drug therapy for Loiasis primarily involves antifilarial agents. Diethylcarbamazine (DEC) is widely used but poses risks for individuals with high microfilarial loads due to the potential for severe adverse reactions. To mitigate this, drugs like albendazole, which is known to be safer in such cases, are being investigated for its potential in clearing Loa loa microfilaremia.
Novel Therapeutic Strategies
Research is also focused on developing novel therapeutic strategies that target specific life cycle stages of the parasite. For example, the use of macrocyclic lactones, which have shown efficacy against the adult worms, is being explored. Additionally, the investigation of drug combinations that can effectively reduce microfilarial density and prevent adverse reactions post-treatment is a promising area of study.
Our Services
Our vaccine development services include antigen discovery, immune response assessment, and preclinical vaccine testing. We utilize state-of-the-art genomic and proteomic tools to identify potential vaccine candidates and evaluate their immunogenicity.
In addition, Protheragen offers a range of therapeutics development services, focusing on the design and optimization of antifilarial drugs. We are committed to enhancing the safety and efficacy of existing therapeutics and exploring new drug candidates that can effectively target Loa loa infections.
Disease Models
- BALB/c Mouse Model for Loa loa Microfilariae (mf): Intravenous administration of L. loa mf isolated from human blood.
- Mongolian Gerbil Model for Loa loa Microfilariae (mf): Intraperitoneal injection of L. loa mf.
Preclinical research is a critical phase in the development of any new vaccine or therapy. Protheragen provides comprehensive preclinical research services tailored to the unique challenges of Loiasis. If you are interested in our services, please feel free to contact us.
References
- Buell Kevin G., et al. "Atypical clinical manifestations of loiasis and their relevance for endemic populations." Open Forum Infectious Diseases. Vol. 6. No. 11. US: Oxford University Press, 2019.
- Dieki Roland, Edouard Nsi-Emvo, and Jean Paul Akue. "The human filaria Loa loa: Update on diagnostics and immune response." Research and Reports in Tropical Medicine 13 (2022): 41.
All of our services and products are intended for preclinical research use
only and cannot be used to diagnose, treat or manage patients.
