Abstract: The invention relates to a process for the preparation of .alpha.- and .gamma.-interferon by isolating the buffy coat fraction of blood, removing the erythrocytes, suspending the leukocytes in a suitable nutrient medium and treating with an .alpha.-interferon inducer and with a .gamma.-interferon inducer, which comprises producing .alpha.-interferon and .gamma.-interferon one after the other in the same leukocyte culture by pre-treating the suspension obtained after the separation of the leukocyte/buffy coat/fraction of blood, removal of the erythrocytes and suspending the leukocytes in a suitable nutrient medium with - or .beta.-interferon, contacting with an .alpha.-interferon inducer, separating the liquid containing the .alpha.-interferon from the cells, if desired recovering the -interferon, washing and suspending the cells in a suitable nutrient medium, treating with a mitogenic agent, separating the liquid comprising .alpha.-interferon from the cells and if desired recovering .alpha.

Abstract: Tri-tetracyclines are complexes of tetracyclines with an amino compound containing per molecule at least a tris (hydroxyalkyl) group and at least a primary or secondary amino group in a molar excess in respect to the tetracycline compound. The complexes have high water solubility and are particularly useful for parenteral administration.