Introduction
Immunoglobulin A (IgA) plays a key role in defending mucosal surfaces against attack by infectious microorganisms.
Indeed, IgA is not just the most prevalent antibody class at mucosal sites, but is also present at signifificant
concentrations in serum. The unique structural features of the IgA heavy chain allow IgA to polymerise, resulting in
mainly dimeric forms, along with some higher polymers, in secretions In humans, there are two subclasses of IgA,
named IgA1 and IgA2. Like all Ig, each subclass comprises a basic molecular unit of two identical heavy chains (HCs)
and two identical light chains (LCs). Each chain begins at its N-terminus with a variable region, which is followed
by a constant region. The LCs are the same in each subclass, but the HCs diffffer within their constant regions,
which are encoded by distinct Cα genes. Two allotypic variants of human IgA2, known as IgA2m(1) and IgA2m(2), have
been characterised. A third IgA2 variant, termed IgA2(n), has been described, but while presumed to be an allelic
form, its penetrance in the population remains to be investigated.
Fig.
1. Schematic diagram of IgA structures-monomeric, dimeric, and secretory IgA. (Nejadmoghaddam M R, et al.,
2019)
Our Services
Creative Proteomics has developed an advanced immunoglobulin profiling sequencing method that uses
HCD + ETD to generate simple, easy-to-read sequence ladders for IgA light and heavy chains. Developed by our
scientists with extensive antibody sequencing experience Compared with the traditional sequencing method, the
antibody de novo sequencing method of the present invention adopts the ionization method of ETD combined with HCD,
which increases the formation of fragment ions, which is suitable for deformed and natural intact antibodies.
At Creative Proteomics, we use HCD + ETD fragmentation to increase coverage. In addition, our
scientists can use the "Database Assisted Shotgun Sequencing" (DASS) technology to combine the advantages
of existing technologies to perform excellent, fast and precise sequencing services for immunoglobulin antibodies.
When similar proteins and known genome sequences exist, we are able to integrate de novo peptide, intensity and
positional confidence scores from databases and homology to find protein sequences with high accuracy.
We have sequenced dozens of immunoglobulin A (IgA) antibodies. Customers only need to provide 50-100 µg of IgA sample
to obtain the amino acid sequence information of the antibody and ensure 100% sequence accuracy.
Creative Proteomics provides professional IgA antibody sequencing services for global customers. Our
team has successfully sequenced thousands of antibodies to help researchers decode their antibodies in a fraction of
the time. Therefore, please contact us if you are interested in our
antibody sequencing services.
References
- de Sousa-Pereira P, Woof J M. (2019) IgA: Structure, Function, and Developability. Antibodies (Basel).
8(4):57
- Greisch J F, den Boer M A, Beurskens F, et al. (2021). Generating Informative Sequence Tags from
Antigen-Binding Regions of Heavily Glycosylated IgA1 Antibodies by Native Top-Down Electron Capture
Dissociation. J Am Soc Mass Spectrom. 32(6):1326-1335.
