Design at the service of science

5/9/2018

Human cytomegalovirus (HCMV) is endemic to populations throughout the world, and 50-80% of the adults in developed nations are sero-positive for this virus. Commercial ELISAs for detecting IgG are very sensitive and specific. Nevertheless, there are several problems regarding IgM detection. One of the difficulties that the diagnostic laboratory has faced over the past 10 years is the lack of agreement between commercial tests for the detection of CMV-specific IgM. This lack of agreement has its roots in the different viral preparations used to detect IgM antibodies to CMV. Rekom Biotech has performed the design of a new CMV recombinant polyepitope chimeric antigen (RAG0109), composed by different sensitive and specific antigenic determinants from some CMV proteins. This recombinant polyepitope chimeric antigen was tested in parallel with other CMV bio-markers such as the Rekom Biotech CMV recombinant proteins pp150 (RAG0091) and pp52 (RAG0090) and pp65 (RAG0016). The in house indirect IgM ELISA assay was carried out by using a battery of pre-validated sera with the commercial ELISA capture IgM test from Vidas:

Figure 1: Indirect IgM ELISA assay. Proteins were coating the plates at a final concentration of 1 µg/ml. All these experiments used anti-IgG as sorbent and anti-IgM-HRP. Sera were used in a 1:100 dilution. P means pre-validated sera by the Vidas test as positive; N means pre-validated sera by the Vidas test as negative.

These preliminary experiments suggest that the recombinant polyepitope chimeric antigen designed and produced by Rekom Biotech, RAG0109, recovers some pre-validated IgM positive sera which are not initially detected by two of the best antigens described in bibliography for CMV diagnosis: pp52 and pp150, showing the presence in merely one antigen of some important epitopes for this specific diagnostic.

To find more interesting information on regards recombinant antigen RAG0109, please click here.

Written by Ana Camacho.