This is unfortunately a non-question (and one with a motive). Firstly because MMT describes normal operations in a monetarist economy. 'Respected economic institutions' are not economies nor are they governments implementing policy in line with anything. The OECD doesn't implement monetary and fiscal operations for, say, the UK. and even if it did for some sort of strange reason, all the same facts about how the system operates would be the same. Same currency issue power, same facts about taxation, same facts about transfer payments, same facts about how loans work, same facts about banking operations, same facts about employment. What is your actual question?
That said, there is indeed a complete department based upon MMT at the Levy Institute Bard College, and University of Missouri Kansas City, where many of these ideas were shaped. Also Melbourne University. And as it has much in common with previous thought in the post-Keynes tradition, it's actually everywhere in parts.