Cross reaction between proteins from Larrea divaricata Cav. (jarilla) and cellular and extracellular proteins of Pseudomonas aeruginosa.

Larrea divaricata is widely used in folk medicine to treat different pathologies, but little is known about its immunological properties. Pseudomonas aeruginosa is an opportunistic pathogen which causes several intrahospitalary infections. We aimed to assess the immunological relation between proteins from a crude extract of L. divaricata Cav. (JPCE) and cellular and extracellular proteins (EP) of P. aeruginosa, as well as to establish the cross reactivity between proteins of both species using a mouse anti-JPCE serum. Protein profiles of JPCE and P. aeruginosa were analyzed by SDS-PAGE. The percentage of similarity of protein bands between these two species was 43-57%. However, JPCE proteins were immunogenic. The reactivity of mouse anti-JPCE antibodies against different fractions was studied by western blot. The anti-JPCE serum detected several antigenic bands on different bacterial proteins. Several common immunoreactive bands were detected (27-100%) when bacterial proteins were incubated with anti-JPCE serum (heterologous reaction) and anti-bacterial proteins serum (homologous reaction). By enzyme-linked immunosorbant assay (ELISA) assays, high titers of anti-JPCE against different types of cellular bacterial fractions were observed (1/1280-1/2080). Our data clearly demonstrate that antibodies elicited with L. divaricata crude extract are able to cross-react with cellular and EP of P.aeruginosa. These findings could be relevant in the development of alternatives therapies for patients suffering intrahospitalary opportunistic infections with P.aeruginosa.