[Incidence, characteristics and clinical importance of autolymphocytotoxins in aplastic anemias]. / Incidence, caractéristiques et importance clinique des autolymphocytotoxines dans les anémies aplastiques.

Sixteen (24%) of 68 patients with aplastic anemia had antibodies cytotoxic to their own lymphocytes before specific disease treatment. These antibodies displayed the characteristics of cold reactive lymphocytotoxins (LTs). No correlation existed between the detection of auto-LTs and a viral or toxic cause of the disease or the patients' HLA genotype. A lower frequency of anti-HLA antibodies was recorded in the pretreatment sera of patients with auto-LTs. However, the response rate to antilymphocyte serum treatment and the outcome of the bone marrow grafts were comparable among the patient's groups with or without pretreatment auto-LTs.

Circulating immune complexes and the prognosis of acute myeloid leukemia.

We studied the relation between the clinical course and the presence of circulating immune complexes at diagnosis and/or during complete remission in 186 patients with acute myeloid leukemia. Patients with immune complexes at diagnosis had significantly fewer complete remissions (32 vs. 94 per cent), remissions of shorter duration (median, 4.3 vs. 15.0 months), and shorter survival times (median, 1.8 vs. 22.3 months) than patients without such complexes (all comparisons, P less than 0.01). All patients with immune complexes during the first two months of remission remained in remission for less than six months, whereas only 11 per cent of patients without complexes within this period had such early relapse. Of 23 patients who relapsed after long remissions, 18 (78 per cent) had immune complexes that preceded hematologic evidence of relapse by three weeks to six months (median, 3.7 months). These findings suggest that circulating immune complexes may reflect an important aspect of the pathophysiology of acute myeloid leukemia, and that measurement of these complexes can provide useful prognostic information at diagnosis and during remission.

[Incidence and specificity of circulating immune complexes in infectious mononucleosis (proceedings)]. / Incidence et spécificité des complexes immuns circulants dans la mononucléose infectieuse.

Occurrence of immune complexes in infectious mononucleosis has been investigated by the 125I Clq binding assay. Increased serum Clq-binding activity was found in 87% of the 23 patients studied during the acute stage of the disease. The serum Clq-binding material detected has properties identical to those of immune complexes. IgG antibodies dissociated from the complexes at acid pH and F (ab)'2 fragments obtained after treatment by pepsin appeared to be directed against the viral capsid antigen of Epstein-Barr virus.

Quantitation of serum complement components and plasma C3d in patients with malignant lymphoma: relation to the stage of the tumor and circulating immune complexes.

Total hemolytic complement activity (CH 50) and complement component levels were measured in 27 patients with Hodgkin's disease and 31 patients with non-Hodgkin malignant lymphoma. CH 50 values were higher than normal in almost all the patients. Increased levels of serum C4, C3 and factor B were observed in 62%, 31% and 19% of these patients, respectively. However, plasma concentration of C3d, a breakdown product of C3, was elevated in 29% of the cases. The hypercatabolism of C3 was not closely associated with the presence of circulating immune complexes, as assessed by the C1q binding assay, nor with the presence of general symptoms in the patients. On the contrary, it appeared to be in relation with the extent of the malignant disease.

Clinical relevance of circulating immune complexes in human leukemia. Association in acute leukemia of the presence of immune complexes with unfavorable prognosis.

The occurrence of circulating immune complexes was investigated in 467 serum samples from 230 leukemia patients using the [(125)I]Clq-binding test. There was an increased serum [(125)I]Clq-binding activity in 40% of patients with acute myeloid leukemia, 23% with acute lymphatic leukemia, 46% in blastic crisis of chronic myeloid leukemia, 12% with chronic lymphatic leukemia, and 13% with chronic myeloid leukemia. In 48 patients, serum was also tested for soluble immune complexes by the Raji cell radioassay; the correlation between results of the two tests was significant. The Clq-binding material had properties identical with those of immune complexes. It sedimented as 14-28s material on sucrose density gradient. It contained IgG which could be dissociated at acid pH. Its Clq-binding properties could be removed after passage through anti-IgG immuno-absorbant or after a mild reduction-alkylation treatment, but were not sensitive to deoxyribonuclease treatment. Circulating immune complexes were found most commonly during the blastic stage of leukemia.Remission took place in 75.4% of patients with no detectable circulating immune complexes at the onset of acute leukemia, but in only 32.7% of those with detected complexes during this period. Median survival times of the former group of patients were more than 18 mo in acute myeloid leukemia and acute lymphatic leukemia and more than 8(1/2) mo in blastic crisis of chronic myeloid leukemia. The corresponding median survival times in the latter patient group were 64, 135, and 90 days. These findings were unrelated to prognostic features already known.

[Circulating immune complexes in human leukemias]. / Complexes immuns circulants dans les leucémies humaines

Occurrence of immune complexes in leukemia has been investigated by the 125I-Clq-binding test. A highly significant serum Clq-binding activity (Clq-BA) was demonstrated in 37% of patients with acute myelocytic leukemia, in 23% of patients with acute lymphocyte leukemia,and in 32% of those in blastic crisis of chronic myelocytic leukemia. Such a high Clq-BA is found only in 13% of cases with chronic leukemia. Incidence of increased serum Clq-BA is significantly higher during the blastic stage of leukemia than in complete remission. There is no correlation between the elevated Clq-BA and infections complicating acute leukemia, or with the chemotherapy given to the patients. The Clq-binding material exhibits properties similar to those of immune complexes.

Anti--DNA antibodies in patients with leukemia and lymphoma.

217 sera from 33 patients with acute myeloid leukemia (AML), 42 with chronic myeloid leukemia (CML), 12 with acute lymphatic leukemia (ALL), 22 with lymphoma, and 20 with other malignant diseases were examined by a radioimmunological technique for the presence of antibodies against DNA. The levels of single-stranded DNA binding activity was significantly higher in all 3 types of leukemia and lymphoma compared to those of healthy controls. In contrast, none of these sera exhibited a positive reaction with double-stranded DNA. In some cases of leukemia, the level of serum anti-DNA antibodies increased after the decrease of the leukocytes count.