Anti-SpCas9 IgY Polyclonal Antibodies Production for CRISPR Research Use.

The CRISPR/Cas adaptative immune system has been harnessed as an RNA-guided, programmable genome editing tool, allowing for diverse biotechnological applications. The implementation of the system relies on the ability to detect the Cas9 protein in biological samples. This task is facilitated by employing antibodies, which exhibit several advantageous features and applications in the context of tropical neglected diseases. This study reports a one-month immunization scheme with the Cas9 protein from Streptococcus pyogenes to produce IgY polyclonal antibodies (anti-SpCas9), which can be rapidly isolated by combining yolk de-lipidation with protein salting out using pectin and ammonium sulfate, respectively. Immunodetection assays indicate that the antibodies are highly sensitive, specific, and useful for detecting the SpCas9 protein in promastigotes of Leishmania braziliensis expressing exogenous SpCas9. Thus, the simple method for producing anti-SpCas9 IgY antibodies will accelerate CRISPR/Cas-based studies in Leishmania spp. This approach serves as a valuable research tool in this parasite model and holds the potential for wide application in various other biological samples, promoting the implementation of the system. In fact, a bioinformatics approach based on the identification of antigenic determinants in the SpCas9 protein suggests the possibility of using the anti-SpCas9 IgY antibodies in applications such as Prime and Base editing.