How to load a value from an address stored in a register?

I have following code:

[Reader]: $80820000 // Current position in ITL. (Item Table List)

LUI T4, @Reader
LW T5, @Reader(T4)  ; current pos in ITL.

([Reader] is my define. I use a MIPS assembler)

Basically 0x80820000 should contain the current position of the ITL. The ITL starts at 0x80800000 and throughout the code it will be added with 4 or 5 and so 0x80820000 will be updated later with 0x80800004, 0x80800008, etc. (I'm writing a script interpreter in asm)

So, now my problem is following: How would I now load the content of the address which is contained in T5 (for example, how would I load the content of 0x80800004 which is contained in T5)? I can't use registers in load instructions for base.