Immunological abnormalities in juvenile myelomonocytic leukaemia.

Immunological studies were performed on 24 children suffering from juvenile myelomonocytic leukaemia. Strikingly high serum immunoglobulin levels with a frequent tendency towards homogeneity and light-chain imbalance were present, together with a high incidence of antinuclear antibodies (52%) and antihuman IgG antibodies (43%). Members of the families of 19 of the children were also studied. A few similar abnormalities were found in eight families, mostly clustered in four of them. The significance of the association of these immunological aberrations with juvenile myelomonocytic leukaemia is at present unknown. In view of the interrelation observed in experimental models between immunological abnormalities and oncogenic viruses the possibility of a common aetiological factor such as a viral infection during fetal life is suggested.