The idea of engineering a liposome with three monoclonal antibodies attached to one liposome presents a daunting challenge. Additionally, the binding affinity between each monoclonal antibody to its antigen must be considered carefully. It is important that the interaction between each antibody and antigen is relatively weak. If one is too strong, the liposome will bind and inject its contents to healthy cells that merely express the antigen in normal levels, leading to cell death. To prevent metastasis, it will be possible to engineer liposomes with the respective antibodies for the three surface antigens as needed. However, if these tumors mutate and/or metastasize and lose the overexpression of CA125, KASH5, or HSF1, assaying the new tumor cells and designing a new treatment in a timely manner will likely be an insurmountable task.
Comments
Combining Sentences?
You might be able to combine the first two sentences and take away the "additionally" as well as the repetition of liposomes in the first sentence: "The idea of engineering a liposome with three monoclonal antibodies presents a daunting challenge as the binding affinities for each antibody to its respective antigen must be considered carefully." You also might be able to combine later sentences in the paragraph in a similar way.
Background
I feel like you should have given some background information about Liposomes. This will enable people reading the text for the first time to follow accordingly. Overall, though, it is well-written.
Conclusion doesn't wrap everything up
You present a concluding remark which leads into a new idea, and then stop the paragraph there. It would be stronger in my opinion if you ended the paragraph a sentence early, and started a new paragraph from that last sentence.