Plants as expression systems of recombinant proteins have proven to be preferable since they are easily grown without the need of expensive care. Important vaccine antigens, monoclonal antibodies and therapeutic agents have already been produced in plants, however not widely used. Transient expression expresses the gene of interest as extrachromosomal without creating a genetically modified organism. The aim of this work was to clone Protein X into the vector pEAQ-HT and transiently express the three proteins green fluorescent protein, Chlamydial trachomatis derived major outer membrane protein and Protein X into the leaves of Nicotiana benthamiana through agroinfiltration. This study aimed to investigate if Nicotiana benthamiana is a suitable plant host for the expression of the proteins. The cloning work was performed with PCR, restriction digests and ligations. The protein expression was analyzed with sodium dodecyl sulphate-polyacrylamide gel electrophoresis and Western blot. Protein X was successfully cloned into the pEAQ-HT vector since almost all colonies displayed the correct insert when analyzed with colony PCR. Green fluorescent protein was expressed in the leaves of the tobacco plant as green, luminescent light was seen under UV light. Sodium dodecyl sulphate-polyacrylamide gel electrophoresis showed a band of the expected size of the major outer membrane protein. However, more research needs to be done on the protein and further optimization on the purification and production process is needed.