Serum lysozyme, antinuclear factors and antibody to native DNA

This work was done in order to investigate the previously reported antinuclear property of lysozyme (LZM). Addition of human or hen egg white lysozyme (hLZM or eLZM) to normal serum and to 11 sera with different types of antinuclear factors (ANF) produced no consistent changes in ANF titre or type. Likewise, absorption of LZM from the sera with bentonite failed to influence ANF titre and, finally, hLZM and eLZM were incapable of binding native DNA (nDNA). Elevated serum lysozyme levels in rheumatic diseases are therefore unlikely to produce false-positive results in tests for antinuclear antibodies.