The reason to use two doses of the same vaccine is simple redundancy: when you are naturally exposed to a live virus it will keep reinfecting you until you're immunised or dead, but a vaccine only exposes you to a finite amount of the thing you're supposed to be training your immune system to fight. There's no reason why two different vaccine brands using the same modified spike protein as a target wouldn't work together as well as they work apart.
That’s true if you believe that it’s actually just a spike protein. However, I don’t believe any of the vaccine companies have actually released the mRNA sequence they are using to create the spike protein.
The reason to use two doses of the same vaccine is simple redundancy: when you are naturally exposed to a live virus it will keep reinfecting you until you're immunised or dead, but a vaccine only exposes you to a finite amount of the thing you're supposed to be training your immune system to fight. There's no reason why two different vaccine brands using the same modified spike protein as a target wouldn't work together as well as they work apart.
That’s true if you believe that it’s actually just a spike protein. However, I don’t believe any of the vaccine companies have actually released the mRNA sequence they are using to create the spike protein.