The present invention is directed to a novel B. microti-based promoter and expression system. The present invention is also directed to a novel method of transfecting B. microti by electroporation, the resulting transfected B. microti parasite cell lines, and optionally, B. microti transfected with a particular novel promoter. In some embodiments, transgenic B. microti parasites that express reporter genes and their uses are provided. In certain embodiments, a multi-functional promoter controls multiple genes, e.g. a bifunctional promoter may control a gene of interest and a reporter or selection gene. The promoter may be particularly useful to control expression of apicomplexan genes and form apicomplexan proteins, e.g., without limitation, those of Babesia parasites. In embodiments, expression systems comprising the promoter are provided. In certain embodiments, B. microti-based systems that express reporter genes are provided. Other expression platforms include surrogate and non-surrogate systems, transgenic parasites, bacterial, fungal, algae, and mammalian platforms, among others. These and other embodiments may be advantageously used for protein expression, diagnostic tools, disease diagnosis, identification of novel genes for drug discovery and vaccine development, recombinant antigens and other immunogens for vaccination, improved vaccine production, gene therapy, analysis of parasite proteins including structure-function analysis, candidate drug screening and profiling, and many related applications. Transfected B. microti parasites expressing reporter genes may advantageously be used e.g. in the study of the B. microti life cycle and host-parasite interaction analysis.

Disclosed herein are transfection complexes comprising at least one cell surface ligand; at least one helper lipid component; and a transfection enhancer. Also disclosed are pharmaceutical compositions comprising the disclosed transfection complexes, and a pharmaceutically acceptable carrier. Further, disclosed are methods of transfecting a cell, the method comprising the steps of: obtaining a transfection complex as disclosed; and contacting a cell with the transfection complex.

Disclosed herein are transfection complexes comprising at least one cell surface ligand; at least one helper lipid component; and a transfection enhancer. Also disclosed are pharmaceutical compositions comprising the disclosed transfection complexes, and a pharmaceutically acceptable carrier. Further, disclosed are methods of transfecting a cell, the method comprising the steps of: obtaining a transfection complex as disclosed; and contacting a cell with the transfection complex.

Disclosed herein are transfection complexes comprising at least one cell surface ligand; at least one helper lipid component; and a transfection enhancer. Also disclosed are pharmaceutical compositions comprising the disclosed transfection complexes, and a pharmaceutically acceptable carrier. Further, disclosed are methods of transfecting a cell, the method comprising the steps of: obtaining a transfection complex as disclosed; and contacting a cell with the transfection complex.

Disclosed herein are transfection complexes comprising at least one cell surface ligand; at least one helper lipid component; and a transfection enhancer. Also disclosed are pharmaceutical compositions comprising the disclosed transfection complexes, and a pharmaceutically acceptable carrier. Further, disclosed are methods of transfecting a cell, the method comprising the steps of: obtaining a transfection complex as disclosed; and contacting a cell with the transfection complex.

Disclosed herein are transfection complexes comprising at least one cell surface ligand; at least one helper lipid component; and a transfection enhancer. Also disclosed are pharmaceutical compositions comprising the disclosed transfection complexes, and a pharmaceutically acceptable carrier. Further, disclosed are methods of transfecting a cell, the method comprising the steps of: obtaining a transfection complex as disclosed; and contacting a cell with the transfection complex.

Disclosed herein are transfection complexes comprising at least one cell surface ligand; at least one helper lipid component; and a transfection enhancer. Also disclosed are pharmaceutical compositions comprising the disclosed transfection complexes, and a pharmaceutically acceptable carrier. Further, disclosed are methods of transfecting a cell, the method comprising the steps of: obtaining a transfection complex as disclosed; and contacting a cell with the transfection complex.