In our experiments we added HOCl-modified serum albumin directly into cell culture media. Viral infection assays in cell culture have the advantage that cell culture ingredients such as (i) antioxidants present in fetal calf serum or (ii) free amino acids like methionine or cysteine present in cell culture medium at 0.2 M are present during the test period. In addition, the mHSA samples produced with low amounts of HOCl showed no inhibitory effect indicating that potential traces of taurine or HOCl are not contributing to the inhibitory effect. We also tested our inhibitor in three different neutralization assays using three different cell types (HeLa, GHOST and TZM-bl) which are well established as host cells, widely used in the HIV literature. Since virus is neutralized under all these different cell culture conditions, all the cell culture ingredients will not suppress the antiviral activity of mHSA. Preincubation of cells with mHSA also had no suppressive effect, showing that mHSA is not non-specifically adsorbed by the cells or their different membrane components. Moreover, the normal growth of other viruses like yellow fever and dengue-2 virus in cell cultures, over a period of up to 9 days, containing mHSA [16] indicates that mHSA has no unspecific overall neutralizing activity or toxic activity that inhibits cellular growth and more especially viral production. We have also tested mHSA in other sensitive cell culture systems (Plasmodium falciparum growth in erythrocytes, Lassa-, Marburg-, SARS virus growth) over a time period of 14 days (data not shown). In all these cell culture experiments we observed no inhibitory effect on pathogen growth indicating that mHSA in not a cellular toxin per se.