Thought the other two were a similar type of vaccine but the Oxford-AstraZeneca on is different from them. Maybe best wait until information is released.
It has a different designation (viral vector as opposed to mRNA) but it works in an almost identical manner.
All three vaccines consist of a lipid membrane, within which is inserted a piece of genetic code with instructions to prompt the ribosomes inside a human cell to produce copies of the SARS-CoV-2 spike protein.
The main difference is in the carrier used to transport the genetic instructions into the human cells.
The Pfizer-BioNTech and Moderna vaccines use a purely artificial lipid membrane designed in a lab whereas the Oxford-AstraZeneca vaccine uses the lipid membrane from a non-replicating adenovirus as the means of carrying the instructions into the body.
Once these different lipid membranes latch onto the human cells and deliver their genetic instructions, the process that then takes place, with the ribosomes reading the instructions and creating the spike proteins, is virtually identical no matter which one of the three vaccines you're talking about.
The human body's reaction to the presence of the coronavirus spike proteins created in this manner should be essentially identical as far as I can tell, whether the instructions to create the spike proteins were carried into the cell by an mRNA or viral vector vaccine.
If I can make an analogy, it's like getting the same model new phone delivered to your house either by a van driver or by a motorbike rider. It doesn't matter how the phone was delivered, it will still work the same once you start using it.