A method of preparing and using gamma delta T cells in the allogeneic or autologous treatment of subjects suffering from virus infection, fungal infection, protozoal infection and cancer.

Provided are a chimeric antigen receptor and an application thereof; said chimeric antigen receptor contains a domain which identifies any one of, or a combination of at least two of, the malarial protein VAR2CSA, a protein tag on malarial protein VAR2CSA, or a compound capable of labeling the malarial protein VAR2CSA. The chimeric antigen receptor can identify the VAR2CSA protein or the recombinant protein (rVAR2) of any one of, or at least two of, the domains of the VAR2CSA protein which can bind to placental-like chondroitin sulfate A (pl-CSA). The VAR2CSA protein or rVAS2 protein is capable of targeting several different types of tumor cells by means of binding to the pl-CSA on the surface of the tumor cell.

The present disclosure provides immunogenic compositions and methods for vaccination with a CelTOS immunogen. The immunogenic composition comprises Babesia, Theileria or Cytauxzoon CelTOS. The immunogenic composition may also comprise CelTOS with structural changes that affect immune recognition.