The fact of the highly polymorphic nature of human immunoglobulin (Ig) V genes suggests that many novel alleles remain to be discovered. Creative Biolabs has established the high-throughput Magic™ platform for large-scale sequencing services. As a long-term expert in the field of immunology, we have developed an automated tool to analyze mutation patterns in repertoire sequence (Rep-seq) data to identify novel V segment alleles. We are proud to introduce this high-quality service to our customers all over the world.
Current Methods to Identify Novel Alleles
Ig proteins, which are expressed on the cell surface as B cell receptors (BCR) and secreted by B cells, are the key components of the adaptive immune system in humans. These Ig proteins are assembled in B cells from two pairs of polypeptide chains, termed heavy and light. The antigen-binding portions are created through the somatic recombination of gene segments, named variable (V), diversity (D), and joining (J). Repertoire properties can now be studied at large-scale through next-generation sequencing (NGS) of rearranged Ig genes. Analysis of repertoire sequence (Rep-seq) data depends critically on the determination of the germline V, D, and J alleles, and several methods work by aligning sequences to a database of known germline V(D)J segment alleles. However, existing databases are incomplete, so it is hard to differentiate novel polymorphisms from the frequent occurrence of somatic hypermutations in Ig sequences. Although some filtering-based methods have successfully identified novel alleles, their sensitivity and specificity have not been evaluated. It is unclear whether this approach can distinguish polymorphic positions from SHM hot-spots. Some recent studies have discovered numerous V segments and alleles not reported in any published databases. The completeness of the germline V(D)J database may greatly influence downstream analysis results, including clinically relevant decision processes. To this end, there are still many alleles needed to be identified.
Fig.1 Repositioning of immunoglobulin alleles in developing B cells (Fisher 2002).
Novel Alleles Identification Service in Creative Biolabs
Since there are no automated methods existing for detection of novel V(D)J alleles, Creative Biolabs has developed an automated tool to analyze mutation patterns in Rep-seq data to identify novel V segment alleles. It includes a sensitive algorithm as well as an Ig genotype determination step, and we use it to correct germline allele assignments from existing V(D)J assignment tools. Applying this tool to Rep-seq data, we are able to identify many new alleles.
Key Advantages of Novel Alleles Identification Service
Creative Biolabs has rich experience in the field of immune repertoire analysis. Our scientists are proficient in providing the service of identification of novel alleles by BCR repertoire sequencing. We are pleased to offer the best service with the most accurate results for our global customers.
Please contact us for more information and a detailed quote.