The reactivity of leukaemic cells to HL-A typing sera

Early diagnosis of relapse in acute myeloblastic leukemia: Serologic detection of leukemia-associated antigens in human marrow

We tested serial bone-marrow samples from 47 adults with acute myeloblastic leukemia in remission for reactivity with heteroantiserums to leukemia-associated antigens, to determine whether imminent relapse could be detected in patients with acute leukemia. Of 26 patients who relapsed by standard morphologic criteria, 21 had increased immunoreactivity of bone marrow for one to six months (mean, 3.7 months) before relapse. High concordance was observed between a positive test and relapse during the period of study (chi-square = 27.53, P less than 0.001). The median time to relapse after a positive test was four months, as compared with the median remission duration of 19 months for the whole group (P less than 0.02, Peto's log-rank analysis). Serologic detection of leukemia-associated antigens in marrow may be a reliable indicator of imminent relapse in acute myeloblastic leukemia.

Modification of HLA antigens in patients with malignancies following hormone therapy

In 23 out of 39 patients with various malignancies, treated with hormones (Prednison, Agostiben, Agovirin, separately, or combined; Prednison plus another hormone) modification of HLA antigens was established. Out of 51 patients with hitherto untreated malignancies HLA modification was demonstrated in 12 cases. This variation is statistically significant (P 0.0006), and suggests hormonal therapy to be one of the causes of HLA modification in malignant tumors. The serological pattern of HLA modification varied: in five patients lymphocyte polyreactivity; in 10, loss of HLA antigens; in six, weakening of HLA antigens and in two, transformation of HLA--A2 IN HLA--A28. The modification was transient in character. It occurred most frequently following administration of Prednison, or Prednison combined with some other hormone, and was unrelated to drug dosage.

Chemotherapy--one of the causes of transient loss of HLA antigens and lymphocyte polyreactivity in patients with blood diseases and malignancies

Modifications of HLA antigens (transient loss or polyreactivity) were found in thirty-two of fifty-five examined patients with blood diseases (leukaemia, reticulosis, reticulo- and lymphosarcoma, lymphogranuloma, erythroblastoma) and malignant tumours. In two cases of acute myelosis transient alteration of HLA-A 2 antigen in HLA-A 28 was demonstrated. The relationship of HLA antigenic modification to chemotherapy was established, both by analysis of individual cases and by statistical evaluation of serological results in patients with or without chemotherapy (0-01 greater than P greater than 0-001). Chemotherapy is thus one of the causes for the development of HLA antigen modifications in blood diseases and malignant tumours.

Normal human sera cytotoxic to cells of human acute leukemia

Eight human sera from healthy individuals with no history of immunization with human transplantation antigens have demonstrated complement dependent cytotoxicity to cells of some patients with active acute leukemia. The antigen(s) detected by these sera are absent from normal and remission lymphocytes and appear most often in ALL patients with a high peripheral lymphoblast count. Some B and T lymphoblastoid cell lines carry the antigen(s) as evidenced by their ability to react with and absorb the antileukemia activity. The data support the existence of at least two overlapping specificities detected by these antileukemia sera. The leukemia antigen(s) show no strong correlation with any known HLA antigen. These observations provide evidence for a human leukemia blast associated antigen or set of antigens which may be immunogenic in man. Their relationship to normal HLA antigens of loci other than A, B or C is unknown.