May have a role in maintaining the integrity of the blood vessels. Has growth promoting activity on endothelial cells, angiogenic activity in vivo and chemotactic activity on endothelial cells in vitro. Catalyzes the reversible phosphorolysis of thymidine. The produced molecules are then utilized as carbon and energy sources or in the rescue of pyrimidine bases for nucleotide synthesis. phosphate + thymidine = 2-deoxy-alpha-D-ribose 1-phosphate + thymine Pyrimidine metabolism; dTMP biosynthesis via salvage pathway; dTMP from thymine: step 1/2. Homodimer. The disease is caused by variants affecting the gene represented in this entry. Belongs to the thymidine/pyrimidine-nucleoside phosphorylase family.