How do I update the Apollo data store/cache from a mutation query, the update option doesn't seem to trigger

I have a higher order component in my react native application that retrieves a Profile. When I call an "add follower" mutation, I want it to update the Profile to reflect the new follower in it's followers collection. How do I trigger the update to the store manually. I could refetch the entire profile object but would prefer to just do the insertion client-side without a network refetch. Currently, when I trigger the mutation, the Profile doesn't reflect the change in the screen.

It looks like I should be using the update option but it doesn't seem to work for me with my named mutations. http://dev.apollodata.com/react/api-mutations.html#graphql-mutation-options-update

const getUserQuery = gql`
 query getUserQuery($userId:ID!) {
    User(id:$userId) {
      id
      username
      headline
      photo
      followers {
        id
        username
        thumbnail
      }
    }
 }
`;
...

const followUserMutation = gql`
  mutation followUser($followingUserId: ID!, $followersUserId: ID!) {
    addToUserFollowing(followingUserId: $followingUserId, followersUserId: $followersUserId) {
      followersUser {
        id
        username
        thumbnail
      }
    }
  }`;
...

@graphql(getUserQuery)
@graphql(followUserMutation, { name: 'follow' })
@graphql(unfollowUserMutation, { name: 'unfollow' })
export default class MyProfileScreen extends Component Profile

...

  this.props.follow({
    variables,
    update: (store, { data: { followersUser } }) => {
      //this update never seems to get called
      console.log('this never triggers here');
      const newData = store.readQuery({ getUserQuery });
      newData.followers.push(followersUser);
      store.writeQuery({ getUserQuery, newData });
    },
  });