Strongyloides stercoralis is a parasitic nematode that infects humans, causing strongyloidiasis, a disease that can range from asymptomatic infection to a potentially fatal hyperinfection syndrome. One of the key components of the immune response to S. stercoralis is the immunoreactive antigen L3NieAg.01.

L3NieAg.01 is a highly immunoreactive antigen that is expressed by the third-stage larvae (L3) of S. stercoralis.
The antigen is recognized by both IgG and IgE antibodies in the serum of infected individuals.
Antibodies against L3NieAg.01 have been shown to play a significant role in protective immunity against S. stercoralis infection.

Studies have also suggested that L3NieAg.01 may be a useful diagnostic marker for strongyloidiasis, as it appears to be highly specific to S. stercoralis and does not cross-react with other parasitic infections.

The use of cDNA and recombinant antigens of S. stercoralis has several potential applications, including:
Diagnosis: S. stercoralis cDNA can be used as a template for PCR-based diagnostic tests, which are highly sensitive and specific for detecting the parasite’s DNA in clinical samples such as feces, blood, or serum. Recombinant antigens, such as the S. stercoralis antigen 5 (SsAg5), can be used in serological tests to detect specific antibodies produced in response to S. stercoralis infection.

Vaccine development: Recombinant antigens of S. stercoralis can be used as potential vaccine candidates to induce protective immune responses against the parasite. For instance, the recombinant form of the S. stercoralis antigen 11 (SsAg11) has been shown to induce significant protection in animal models, suggesting its potential as a vaccine candidate.

The use of recombinant proteins/cDNA in academic research and therapeutic applications has skyrocketed. However, in heterologous expression systems, successful recombinant protein expression is dependent on a variety of factors, including codon preference, RNA secondary structure, and GC content. When compared to pre-optimization, more and more experimental results demonstrated that the expression level was dramatically increased, ranging from two to hundred times depending on the gene. Bioclone has created a proprietary technology platform that has resulted in the creation of over 6,000 artificially synthesized codon-optimized cDNA clones (cloned in E. coli expression Vector), which are ready for production of the recombinant proteins.