[Immunofluorescence study of lactoferrin-synthesizing thymus cells].

Lactoferrin-synthesizing cells were detected in the human thymus by immunofluorescence. LF cells in the thymus were shown to be more numerous, to possess greater secretory activity, and to appear earlier in the process of embryonal development as compared to the organ producing this protein (salivary gland). The data obtained suggest that in the thymus, lactoferrin apart from its known functions, bacteriostatic and ferrous iron-binding ones, acts as a heteroorgan antigen, i.e. provides lymphocytes of the thymus with information on this protein structure during natural immunologic tolerance induction.