Great Defenders of Catholic Dogmas (a list)

All the great defenders of Catholic dogmas are both saints and doctors of the Church: 

• St Athanasius manfully defended the deity of Christ
   
• St Basil, St Gregory Nazianzus, St John Chrysostom and St Hilary defended the dogma of the Holy Trinity
   
• St Basil, in particular, defended the deity of the Holy Spirit
   
• St Jerome manfully defended the perpetual virginity of our Lady
   
• St Cyril manfully defended Mary as "Mother of God"
   
• St Leo manfully defended the humanity of Christ and the hypostatic union of the two natures of Christ
   
• St John Damascene manfully defended the images of Christ, Mary, and the Saints   

• John Duns Scotus manfully defended the doctrine of Mary's Immaculate Conception

Note: All are both saints and Doctors of the Church except John Duns Scotus. Taylor Marshall has a great post on this.  John Duns Scouts - Our Next Saint and Doctor of the Church