The present invention provides a human thioredoxin (TRDX) and polynucleotides which identify and encode TRDX. The invention also provides genetically engineered expression vectors and host cells comprising the nucleic acid sequences encoding TRDX and a method for producing TRDX. The invention also provides for agonists, antibodies, or antagonists specifically binding TRDX, and their use, in the prevention and treatment of diseases associated with expression of TRDX. Additionally, the invention provides for the use of antisense molecules to polynucleotides encoding TRDX for the treatment of diseases associated with the expression of TRDX. The invention also provides genetically engineered expression vectors and host cells comprising the nucleic acid sequences encoding TRDX in the production of recombinant proteins. The invention also provides for the use of purified TRDX in the production of recombinant proteins. The invention also provides diagnostic assays which utilize the polynucleotide, or fragments or the complement thereof, and antibodies specifically binding TRDX.