Below is the list of tables from the database along with their columns and datatype. Need to generate an accurate SQL query for the question.
Only use the columns present in the respective table. Only use the columns which are required to generate the SQL query. Only use table joins if required and not otherwise.

### Tables ###
TABLE: CREATE TABLE table_28211213_2 (institution VARCHAR, team_nickname VARCHAR)

### Question ###
When gray wolves is the team nickname how many institutions are there?

### Accurate SQL ###

SELECT COUNT(institution) FROM table_28211213_2 WHERE team_nickname = "Gray Wolves"