How does IFN-beta influence the progression of MS?

Nobody knows for sure, but several research teams are trying to find out. Studies posted to PubMed over the past few days suggest that it:

a) decreases the levels of proteolytic enzyme MMP-9 and increases the MMP inhibitor TIMP-2 (Abstract);

(b) lowers mean IgG concentrations in patients with progressive MS (Abstract);

(c) makes T-cells more susceptible to apoptosis by decreasing expression of inhibitor of apoptosis (IAP) proteins in these cells (Abstract); and

(d) helps preserve the integrity of the blood-brain barrier by maintaining the location of tight junction-associated molecules zonula occludens-1 and -2 (ZO-1 and ZO-2) at the cell borders in human brain endothelial cells (Abstract).