M. R. Halie

The clinical expression of hereditary protein C and protein S deficiency:: a relation to clinical thrombotic risk-factors and to levels of protein C and protein S

We investigated 103 first-degree relatives of 13 unrelated protein C or protein S deficient patients to assess the role of additional thrombotic risk factors and of protein C and protein S levels in the clinical expression of hereditary protein C and protein S deficiency. Fifty-seven relatives were protein C (37) or protein S deficient (20). Thromboembolic events occurred in 30% of protein C deficient and in 35% of protein S deficient persons, compared with 3% and 0% in their normal controls respectively (P < 0.05). In protein C deficient persons, the median thromboembolic event-free survival was 55 years, while in protein S deficiency this interval was 33 years (P = 0.047). In the protein C deficient group 64% of the initial events occurred spontaneously, as did 71% in the protein S deficient group. Recurrent thromboembolic events were more often associated with concomitant risk factors than the initial events: 64% and 50% in persons with protein C or protein S deficiency respectively. These findings suggest a substantial role for these risk factors in triggering thromboembolic events in deficient persons. Protein C antigen and protein S antigen levels were similar in symptomatic and asymptomatic deficient persons. Total, but not free, protein S antigen levels were significantly higher in symptomatic protein C deficient persons, as were protein C antigen and activity levels in symptomatic protein S deficient ones. The clinical implication of this finding is not yet clear.

SMALL CELL LUNG-CANCER AND THE INFLUENCE OF CHEMOTHERAPY ON CFUCS IN BONE-MARROW

To determine the optimal moment for the harvesting of bone marrow for autologous transplantation, the authors did serially colony forming units in culture (CFUc) counts in a group of 42 patients with small cell lung cancer (SCLC) before and after remission induction chemotherapy and subsequent maintenance chemotherapy. Disease stage did not influence the CFUc count except in patients with bone marrow metastases; this resulted in either abnormally low or abnormally high CFUc counts, probably dependent on the degree of invasion. After 2 courses of induction chemotherapy, the number of CFUcs was 3.1‐fold higher than before therapy. After 4 courses, the CFUcs number was comparable to the pretreatment value. An inverse correlation was found between the degree of hematologic toxicity (expressed as leucocytes count) and the increase of CFUcs after induction chemotherapy. The number of CFUcs decreased during prolonged chemotherapy to low levels after 1 year. Harvesting of bone marrow is probably done best shortly after induction chemotherapy.

Efficacy and Safety of a Monoclonal Purified Factor VIII Concentrate: 5-Year Follow-Up in Previously Treated HIV-Negative Haemophiliacs

The efficacy and safety of a monoclonal purified factor VIII concentrate (Hemofil M) were assessed in a historically controlled study in 22 HIV-negative patients with haemophilia A, previously treated with various concentrates. Data from 5 years of follow-up were compared with those from the preceding 6 months. Factor VIII consumption remained unchanged. A temporary increase in the number of reported bleedings was attributed to more frequent follow-up visits in the first year. Allergic reactions, inhibitor formation and HIV infection were not seen. Liver function parameters fluctuated in individual patients, and were not related to the ultrapure concentrate used. No clinical evidence of liver insufficiency was seen. The number of CD4-positive lymphocytes was stable, while platelet numbers showed a remarkable increase. We conclude that in previously treated HIV-negative haemophiliacs, treatment with a monoclonal purified factor VIII concentrate is efficacious and safe with regard to HIV transmission, allergic reactions, induction of inhibitors, and deterioration of immune abnormalities.

Lymphocyte characteristics and function in paroxysmal nocturnal haemoglobinuria.

SummaryIn six patients with paroxysmal nocturnal haemoglobinuria (PNH) lymphocyte studies were performed to investigate whether the observed immunological dysfunction could be ascribed to a defect in lymphocytes as result of the PNH characteristics, or to an imbalance between T-cell subsets.The PNH characteristics were studied by means of the effect of serum and acidified serum on Indium111-oxine labelled lymphocytes. No increase in release of Indium111-oxine was found when lymphocytes were exposed to acidified sera. Thus a complement mediated lymphocyte lysis in PNH could not be demonstrated.T-cells were defined by monoclonal antibodies, directed at total T-cells (OKT3), helper T cells (OKT4) and suppressor/cytotoxic T-cells (OKT8). In two of the six patients a decreased proportion of OKT3 cells was found, while a significantly depressed ratio of OKT4/OKT8 cells was present in the whole group. No obvious correlation was found between a functional assay — the concanavalin-A suppressor cell activity — and the ratio of OKT4/OKT8 positive cells.It is concluded that the PNH characteristics could not be demonstrated in the lymphocytes; and that the immunological dysregulation in PNH may be ascribed to an imbalance of T-cell subsets, while a decreased number of monocytes, defined by the monoclonal antibody OKM1, may contribute to this defect.

Effect of sera from patients with Hodgkin's disease on normal donor lymphocytes containing parallel tubular structures

SummaryNormal donor peripheral blood mononuclear cells incubated for 24 h with sera from patients with Hodgkins disease were investigated by electron microscopy for the presence of parallel tubular structures (PTS) and/or amorphous electrondense granules (large granular lymphocytes = LGL). In comparison with normal human serum, 14 out of 29 sera of the patients induced a marked increase in the percentage of LGL. From a limited number of experiments it was likely that this increase is paralleled by an increase in Fcγ receptor-bearing cells after the incubation. This serum effect did not show a correlation with the number of Fcγ receptor-positive lymphocytes in the peripheral blood of the patients.A difference in the induction effect could be demonstrated between the sera from patients with a favourable and those with an unfavourable clinical course, but this distinction was not absolute. The presence of absence of splenic involvement by Hodgkins disease does not apparently influence the effect of the sera.From experiments using sera positive for immune complexes or anti-Epstein-Barr virus antibodies, it seems unlikely that these factors are responsible for the observed increase in LGL.

IMMUNOELECTRON MICROSCOPIC CHARACTERIZATION OF LYMPHOCYTES CONTAINING PARALLEL TUBULAR STRUCTURES INDUCED BY NATURAL BUT NOT RECOMBINANT INTERFERON-ALPHA

Activation of natural killer (NK) cell activity is one of the immune functions which can be altered by the interferons (IFNs). We previously incubated healthy donor peripheral blood lymphocytes (PBMC) in the presence of natural (n) IFN-alpha and found induction of granular lymphocytes, a proportion of which expressed CD 8 and CD 57. In the present study we further delineated the membrane characteristics of these induced granular lymphocytes and observed the greatest proportion to be CD 16+, with lesser proportions positive for CD 8, CD 57, or coexpressing CD 16 and CD 8. Thus, nIFN-alpha-induced granular lymphocytes have both the morphological and membrane characteristics of functional NK cells. However, in contrast to nIFN-alpha, incubations with recombinant (r) IFN-alpha and n- and rIFN-gamma were found to only enhance NK activity; the concomitant increase in granular lymphocytes as observed after nIFN-alpha incubation was absent. Therefore, even though the different IFNs applied had comparable effects on the function of cytotoxic effector cells, taking into account the observed morphological discrepancy, the unknown mechanisms or pathways by which this is achieved are apparently not identical.

CELL CULTURE AND IMMUNE FUNCTION TESTS

Concerning the role of white blood cells in blood transfusions different aspects have to be considered: 1. Antibody formation against HLA and cell specific antigens by the patients immune system. 2. The influence of transfusion on the composition of different white blood cell populations in the patient. Several studies have demonstrated that supportive hemotherapy may influence the immune system: improvement of graft rejection in renal transplantation [1]; alterations in lymphocyte subpopulations in hemophilia patients [2]. 3. The properties and the function of the white blood cells of the donor, which have been collected for transfusion. For instance granulocytes used in transfusion for granulocytopenic patients. But most important are here perhaps the bone marrow grafts now that bone marrow transplantation has become an established procedure in the treatment of hematological disorders.