Stabilised cell preparations with heavy metal compounds and lysing agent for leucocytes comprising urea

摘要

A stabilised cell preparation in which the stabilising agent comprises an effective amount of a heavy metal compound. The cells are preferably whole blood or leucocytes, and heavy metal may be a transition metal, especially chromium, particularly as the chloride. The stabilising agent may comprise an aldehyde, particularly paraformaldehyde. Whole blood preparations comprising leucocytes are stabilised by the addition of a stabilising agent. A stabilising agent for cellular materials which comprises an aqueous solution of a heavy metal compound and an aldehyde. The heavy metal compound, preferably a transition metal compound, and the aldehyde, especially paraformaldehyde, may be present in an amount of 0.1 to 0.5% w/v at at ratio of 5:1 to 1:50, respectively. A lysing agent for the differentiation of leucocytes which comprises a solution of an ammonium salt or a quaternary ammonium salt and a urea, the concentration of urea in the solution and the pH of the solution being sufficient to inhibit the monocytes from down-regulating the CD14 antigen sufficiently to allow their detection by immunological means. The concentration of the ammonium salt and urea is preferably 0.05 to 0.5M at a pH of 6.8 to 7.8.