Preheat oven to 350 degrees F. To a medium sized bowl add in the boxed cake mix, egg whites, jello packet, add the water stir well. Carefully fold in the blueberries.
In a smaller bowl add in the cream cheese, sugar and egg beat until smooth. Spray a loaf pan with non-stick spray, then pour half of the cake mixture in, pour all of the cream cheese mixture over the top, then pour the remaining cake mixture on top. Bake for 55 minutes or until the center has set.
Make the icing now. To a small bowl add in the powdered sugar, vanilla extract and lemon juice, whisk well until smooth (if it is too thick add in 1 tbsp of milk) once out of the oven drizzle the glaze on top.