Abstract

Red Blood Cells (Erythrocytes), the most abundant blood cells in the blood, are very easily to be collected and isolated from the whole blood via direct low-speed centrifuge[1]. Therefore, they are promising carriers because of their biocompatibility, bio-degradablilty, various ways and large volume for encapsulation, longer life-span and protection to the drugs and other non-target tissues[2, 3]. In addition, the most important is that they can enter the tissues, especially the cancer tissue, via micro-vessels, which offer us the opportunity to deliver the drugs to the corresponding tissue specifically. 

An antibody, Ig (immunoglobulin), is used by the immune system of vertebrates to identify, recognize and neutralize the unique molecular structure of foreign objects (also called pathogen or antigens). The antibody could recognize the antigen specifically and so that it process the best targeting capacity to antigen on the surface of the cells, such as tumor cells[4, 5]. 

In addition, we chose photosensitisers as the loading drug model into RBCs because photodynamic therapy (PDT) is a successful treatment modality used in various diseases, including certain cancers. Also, they can utilize the energy to induce photochemical reactions to produce lethal toxic agents (reactive oxygen species (ROS) and radicals)) in cellular environment ultimately result in cell death to destruct the RBCs and release the drug to achieve photodynamic Treatment (PDT)[6]. 

Drugs can either be encapsulated within RBCs or be coupled to their surface according to the previous study. Therefore, we bind the modified antibodies on the surface membrane of the RBCs via lipid insertion to enable the RBCs possess the targeting capability and load the photosensitisers into the internal of RBCs to achieve our targeted therapies on tumors. Anti-HER2 and SKOV3 cells were chosen to perform study in this research project.  

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