Abstract: A cell line, identified by the reference LDV/7, was established from peripheral blood leucocytes of a 75 year old male volunteer, and may be propagated by culturing the cells in a suitable nutrient culture medium. The cell line may be used in the production of immunological material.

Abstract: Gamma-globulins and immune nucleic acids, both specific to a given antigen, are produced by culturing in vitro an inducible cell line in the presence of specific immune nucleic acids or specific immune dialysates obtained either from human or animal donor lymphoid cells sensitized to said specific antigen or from cells of a previously induced cell line sensitized to said specific antigen, or in the presence of the liquid phase of a culture of a previously induced cell line sensitized to said specific antigen; and extracting gamma-globulins from the liquid phase of the thus induced cell culture and/or extracting the immune nucleic acids from the cells so cultured. Specific immune dialysates may also be produced by a similar process.