Junia

A person of this feminine Greek name was mentioned as being of note among the apostles; another translation said she was an apostle in Rome. Rom:16:7: Salute Andronicus and Junia, my kinsmen, and my fellow prisoners, who are of note among the apostles, who also were in Christ before me.  In all of the scriptures, it is never mentioned that Jesus' Apostles congregated in Rome; therefore she could have been a member of a Gentile Leadership group - Apostles or missionaries.




Priscilla

Of course Aquila and Priscilla, a husband and wife team who served the Lord along side Paul.  When a very learned man in the scriptures, Apollos preached boldly, Priscilla and her husband were astute enough in the scriptures to expound the way of God to him more fully.  She was included in Paul's missionary journey to Syria.




The Elect Lady

John wrote to correct a leader of the church.  Many Scholars hold that the Elect lady was indeed the leader of a church in Syria. 
This person, must have been very elevated in her ministry. Definitions as follows, elect, selected, or chosen and the word lady here means the feminine counterpart for adoni
, kuria- meaning supreme authority, lord or master.  There was also an elect sister.