Reading Data from a Mainframe Mailbox

I have a task to load data directly from a mainframe into SQL Server table.

Here are the details

Mainframe: ftp.wen.trm.com
File in mainframe mailbox: test.dat
Full file path in Mainframe: ca.s2.ts.rb.a20.test.dat

Because of the nature of the data and for efficiency, I don't want to use ftp to download the file first.

If possible, I just want to use VB.NET (or C#) to read the data directly and then store it in a SQL Server Table.

Please, can someone here explain (possibly with the READ script) how I can read this data?

Thanks.