The present invention relates to a method for the preparation of a mycobacterial lysate comprising the steps of: a) contacting a sample comprising at least one Mycobacterium species with a composition having the activity of degrading the cell wall of a Mycobacterium species, b) incubating the sample for a distinct period, and c) isolating the mycobacterial lysate resulting from step b) thereby obtaining the mycobacterial lysate. Moreover, the present invention relates to the mycobacterial lysate obtained by the method of the present invention and further to a vaccine composition comprising the mycobacterial lysate, an antibody or antibody fragment generated with the mycobacterial lysate or the vaccine, and a pharmaceutical composition comprising the antibody or antibody fragment.
