Circulating immune complexes and the prognosis of acute myeloid leukemia

An Introduction to Survival Analysis: Factors Influencing the Duration of Breast Feeding

Life table survival analysis is a technique for examining the effect of one or more independent variables on the time lapse between an initial event such as diagnosis of a disease and a terminal event such as complete remission or death. The method is based on a prospective study design with thorough follow-up of cases but it also takes account of cases lost to follow-up. There is considerable potential for applica tion of this technique in sociology, demography and psychology. In this paper, life table survival analysis is described and an example is given of analysis of factors influencing the duration of breast feeding.

What would Karl Landsteiner do? The ABO blood group and stem cell transplantation

ABO blood group antigens, of great importance in transplantation and transfusion, are present on virtually all cells, as well as in soluble form in plasma and body fluids. Naturally occurring plasma IgM and IgG antibodies against these antigens are ubiquitous. Nonetheless, the ABO blood group system is widely ignored by many transfusion services, except for purposes of red cell transfusion. We implemented a policy of transfusing only ABO identical platelets and red cells in patients undergoing stem cell transplantation or treatment for hematologic malignancies. Major bleeding episodes have occurred in about 5% of patients undergoing induction therapy for acute leukemia as compared with 15-20% in the literature. Overall survival times appear to be superior to that in historical cohorts. In 2002-2004, treatment-related mortality at 100 days in our Blood and Marrow Transplant Unit was 0.7% for autologous transplants (n=148), 13% for sibling allogeneic transplants (n=110), and 24% (n=62) for matched unrelated allogeneic transplants, suggesting that our approach is safe. We speculate that more rigorous efforts on the part of transfusion services to provide ABO identical blood components, and to remove incompatible supernatant plasma, when necessary, might yield reduced morbidity and mortality in patients undergoing stem cell transplantation.

Circulating immune complexes in leukaemias and lymphomas

Circulating immune complexes (ClC) were estimated in 78 patients of leukaemias and lymphomas by Clq deviation ELISA and PEG assay. In all leukaemias a significant elevation in ClC was seen at the time of first presentation. While in ALL a decrease occurred on therapy as partial or complete remission was achieved, no such fall was seen in AML or CML-BC when treated. ClC levels were much higher in non-Hodgkins lymphoma than in Hodgkins disease and showed a direct correlation with B symptoms and activity of the disease. The ClC levels were highest in null-ALL followed by those in common ALL and T-ALL. The mean duration of remission in patients of ALL without elevation in ClC was much longer than in those with ClC.

Circulating immune complexes and chemotherapy response in patients with head and neck cancer

An assay which could prospectively predict a response to chemotherapy prior to instituting therapy would be beneficial, especially for nonresponders. We evaluated at random a total of 50 patients with previously untreated stage III and IV head and neck squamous cell carcinoma for T-cell subsets and levels of circulating immune complexes (CIC). Of this group 23 patients had induction chemotherapy as their first modality of treatment. These patients received standard protocols of therapy consisting of cisplatin, 5-fluorouracil, methotrexate, and bleomycin. Of the laboratory measures assessed, only CIC correlated with clinical response to chemotherapy [no response (NR), partial response (PR), complete response (CR)] at the completion of the induction period (two to four cycles). Levels of CIC were determined by a polyethylene glycol (PEG) precipitation assay, and measured by spectrophotometry at 280 nm. In our population of all head and neck cancer patients, CIC were elevated (mean +/- SD values: 0.475 +/- 3.8 compared with controls: 0.184 +/- 0.07). In the NR group, the mean +/- SD was 0.707 +/- 0.43 (P = 0.001). Complete responders had a mean value of 0.332 +/- 0.21; partial responders had a mean value of 0.255 +/- 0.13. On the basis of the values determined, patients with markedly elevated levels of CIC would be predicted to respond poorly, or not all, to current induction chemotherapy protocols.

Atypical bullous pyoderma gangrenosum associated with myeloid malignancies

Atypical bullous pyoderma gangrenosum was diagnosed during the course of a myeloid malignancy in three patients. One patient had chronic myeloid leukaemia, one acute myeloid leukaemia, and the third, refractory anaemia with excess of blasts. This atypical form of pyoderma gangrenosum has been specifically associated with myeloid malignancies. The atypical appearance of the skin lesions and the clinical context in which they arose caused the true diagnosis to be delayed in all cases. Treatment with steroids was associated with rapid healing of the skin lesion. The histopathological changes in the skin biopsy specimens from these cases were non-specific, and although the histology was considered to be atypical of pyoderma gangrenosum in one case, the unusual features could be attributed to the patient's neutropenia. (Skin biopsy was performed to exclude other specific pathology). Atypical bullous pyoderma gangrenosum is an uncommon association of the myeloid malignancies. It may remain unrecognised and should be considered more often.

Prognostic role of antibody reactivity to melanoma

Antibody reactivity against cultured allogeneic melanoma Y-Mel 81:180 was studied in 43 patients who participated in an adjuvant trial for stage I and II melanoma. Serum samples were obtained at trial entry within 2 mo of definitive surgery. At the time of serum acquisition, all patients were free of disease by physical examination and routine radiologic and laboratory parameters. Serum antibody reactivity was tested for by protein A hemadsorption before and after acid dissociation and ultrafiltration of serum. We have previously shown that this technique for immune complex dissociation augments autologous antibody reactivity. Results of serum antibody reactivity were scored by an investigator blinded to the patient's clinical status. Of the 43 patients studied, 15 relapsed and 28 remained disease-free. At study entry, there were 25 stage I patients and 18 stage II patients. Breslow depth was 3.25 +/- 2.5 mm in relapse patients and 1.67 +/- 1.1 mm in disease-free patients. The presence and titer of antibody directed against melanoma in either native serum or serum dissociated from immune complexes was found to be associated with eventual relapse (P = 0.0001). When results were subgrouped by stage of disease, Breslow depth, and hypopigmentation, antibody reactivity was still correlated with eventual relapse. The incidence and titer of antibody reactivity against melanoma appears to be a new prognostic factor in predicting eventual disease recurrence.

Effects of ex-vivo plasma adsorption over protein A sepharose in acute leukemia

Plasma adsorption over immobilized Staphylococcus aureus Cowan I has resulted in tumor regression in several animal and human trials. Protein A, because of its ability to bind IgGs has been considered as the effective component of Staphylococcus aureus. In 4 patients with acute leukemia, a plasma volume of 1500 cm3 was passed in an ex-vivo system over immobilized SpA-Sepharose and then reinfused. Almost all of the IgGs contained in the plasma volume could thus be removed. Toxic side-effects were mild. No significant clinical improvement could be obtained. Plasma incubation with SpA did not modify blast cell viability or leukemic progenitor cell growth. Along with others, this study shows that Protein A is probably not the mediator of the tumoricidal responses observed in studies using adsorption over Staphylococcus aureus Cowan I. The ex-vivo system prepared for this study could also be used for plasma IgG removal for the treatment of autoimmune or immune-complex related disorders.

Detection of a retrovirus-related glycoprotein in immune complexes from patients with hematopoietic disorders

Human sera from normal and leukemic individuals were found to contain various amounts of an antigen with determinants related to p15E and reverse transcriptase of retroviruses. Using a specific monoclonal antibody and the immuno-affinity purified antigen, we surveyed a series of sera and plasmas from normal individuals and hematological patients by competition radioimmunoassays and binding assays directed against this specific protein. It was detected in all the samples at various levels. The level of this 74-kd glycoprotein appeared to be related to a stimulation of the hematopoietic system. No free antibodies were found that could recognized the labelled purified antigen. Only immune complexes prepared from the blood of some hematological patients contained the specific antigen, but complexes prepared from the blood of normal individuals did not.

Clinical utility of assays for circulating immune complexes

There are now many assays for the quantification of circulating immune complexes, each with distinct specificity and sensitivity. In a wide variety of rheumatic, infectious, neoplastic, and metabolic conditions, levels of circulating immune complexes may be elevated. In select situations, determination of circulating immune complex levels may help clinicians in the management of their patients. In lupus erythematosus, circulating immune complex levels, in conjunction with other immune parameters, may provide more insight into the disease course and activity than assessment of end organ parameters alone. In the differential diagnosis of infective endocarditis, serial levels of circulating immune complexes may provide evidence of effectiveness or failure of treatment. There is evidence that assays for circulating immune complexes may be of potential benefit in the management of Lyme disease and acute myelogenous leukemia.

The next 10 years in the treatment of pelvic infections

The future developments in the treatment of pelvic infections in women are based on recent changes. There is an expanded knowledge of the complex multibacterial nature of pelvic infections, the clinical view of salpingitis has radically changed, and there have been great modifications in antibiotic treatment strategies with particular emphasis on anaerobes and Chlamydia. In the next 10 years, the following new developments may be expected. In the diagnosis of pelvic infection, there will be new efforts to have better clinical tests and the use of nonspecific and specific laboratory tests. The rapid identification of Neisseria gonorrhea, group B beta-hemolytic Streptococcus, Chlamydia, and Bacteroides fragilis would be an important laboratory aid. The treatment of pelvic infection will not be significantly altered by the introduction of new antibiotics. There will be an emphasis on new combinations of currently available antibiotics and studies that focus on the long-term follow-up of treated patients. In the understanding of the pathophysiology of pelvic infections, the importance of the spermatozoa as a carrier of bacteria and the potent immunosuppression due to seminal fluid will be investigated in detail, along with a greater emphasis on treatment of the male.

Antigens and circulating immune complexes related to the primate retroviral glycoprotein SiSV gp70: prevalence and distribution in human sera

We have shown previously that antigens and also circulating immune complexes related to the primate retroviral envelope glycoprotein SiSV gp70 correlate with early mortality and survival of 56 patients with acute leukemias and chronic myelogenous leukemia in blast crisis. The prevalence and general distribution of these antigens and immune complexes in human sera was therefore of obvious interest. We now report an analysis of a total of 200 sera from 166 patients. Of these 113 sera were obtained from 84 patients with acute or chronic leukemias and 87 from 82 non-leukemic subjects, including laboratory workers and patients with non-leukemic neoplasias. Antigens and immune complexes were determined by enzyme-linked immunosorbent assays (ELISA). The anti-SiSV gp70 antiserum used predominantly recognized the protein moieties of the glycoproteins. The distribution of SiSV gp70-related antigens and immune complexes was similar among leukemic and non-leukemic sera. The prevalence of SiSV gp70-related antigens was 53% and of SiSV gp70-related immune complexes 49% in all sera. SiSV gp70-related antigens were detected in a somewhat higher proportion of non-leukemic (69%) than leukemic sera (40%), whereas SiSV gp70-related immune complexes and cross-reactive antibodies were more evenly distributed in leukemic and non-leukemic sera (in 46 and 51% of leukemic and 54 and 51% of non-leukemic sera). Presence of antigens correlated with presence of SiSV gp70-related immune complexes in 71% of all sera, but in 13% of all sera antigens were detectable only by determining SiSV gp70-related immune complexes. Total circulating immune complexes did not correlate with SiSV gp70-related immune complexes. The origin and pathophysiological role of the antigens are discussed.

Serum immunosuppressive acidic protein in adult T-cell leukaemia (ATL)

The availability of serum immunosuppressive acidic protein (IAP) as a marker of subtypes of adult T-cell leukaemia (ATL) was examined. Serum IAP levels were measured in 34 patients with ATL (18 typical, 9 atypical and 7 smoldering), 7 healthy carriers of ATLA antibody and 53 healthy controls. The mean value of serum IAP was significantly higher in patients with typical ATL (897.8 +/- 502.4 micrograms/ml) than in those with atypical ATL (426.7 +/- 106.6 micrograms/l), smoldering ATL (310.0 +/- 51.3 micrograms/ml), healthy carriers of ATLA antibody (302.9 +/- 39.5 micrograms/ml) and normal controls (350.5 +/- 73.2 micrograms/ml). Serial determinations of IAP revealed that the level was correlated with the clinical course in patients with ATL; there was a difference in the prognosis of patients with high and normal levels of IAP (P less than 0.05). Thus, routine measurement of serum IAP seems useful in differentiating typical, atypical and smoldering ATL and also in evaluating the prognosis of patients.

Fibronectin assays and their clinical application: a review

Cold insoluble globulin (fibronectin) was discovered 30 years ago but recently there has been a remarkable growth of knowledge concerning its interaction with the cell cytoskeleton and its role in cell-cell and cell-matrix adhesion. The protein is also a major plasma opsonin with a role in regulating fixed macrophage activity and it is this area in which clinical applications are now beginning to develop. Methods are discussed for measuring the concentration of the protein and its opsonic function in vitro, and for the evaluation of fixed macrophage function in vivo. Also discussed are the metabolism of the protein, the implications of opsonin depletion in patients with serious injury or infection and the attempts to reverse this with plasma protein replacement therapy.

Acute myeloblastic leukemia and sarcoidosis. Implications for pathogenesis

A disorder characterized by anemia and neutropenia due to impaired bone marrow function and a multisystem noncaseating granulomatous (NCG) disorder typical of sarcoidosis, culminated in acute myeloblastic leukemia (AML) in a patient after 6 years of observation. Linkage between the leukemia and sarcoidosis is suggested by a precedent case report, by the statistical remoteness of a fortuitous concurrence, by numerous reported instances of regional or systemic NCG accompanying a variety of malignancies, and by evidence of AML immunogenicity. It appears possible that the sarcoidosis in this patient represented a tissue reaction to the AML.

Antigens and circulating immune complexes related to the primate retroviral glycoprotein SiSVgp70. Indicators of early mortality in human acute leukemias and chronic myelogenous leukemias in blast crisis

Human sera contain antigens and also circulating immune complexes that are related to the primate retroviral envelope glycoprotein gp70 of simian sarcoma/simian sarcoma associated virus (SiSV) and of gibbon ape leukemia virus (GaLV). SiSVgp70 related antigens (AG) and immune complexes (IC) are detected both in leukemic and in nonleukemic sera. In a further analysis of these data, the prognostic significance of SiSVgp70 related AG and IC in leukemic patients was examined. The data show that the presence of SiSVgp70 related AG and IC indicates an unfavorable clinical course and a shorter survival time in acute leukemias (AL) and in chronic myelogenous leukemia in blast crisis (CML-BC). Survival data of 56 of 64 patients tested were analyzed (38 patients with AL and 18 patients with CML-BC). Patients with AL whose sera were positive for SiSVgp70 related AG and IC had a median survival time of 9.5 months after diagnosis versus 16 months for patients negative for such AG and IC. This difference in survival time was more pronounced for patients with acute nonlymphocytic leukemia (ANLL) (6.5 versus 19 months). The difference in survival between SiSVgp70 related AG- and IC-negative and positive groups as tested by life table analysis (log-rank test) is significant (P less than 0.05). Patients with AL of the AG- and/or IC-positive group had fewer complete remissions. Patients who had no remissions belong to the AG- and/or IC-positive group (P = 0.06). Patients with CML-BC whose sera were positive for SiSVgp70 related AG and/or IC had a median survival time of 2 months after diagnosis versus 7 months for patients with sera negative for such AG and IC. As tested by log-rank test, survival curves between the two groups are significantly different (P less than 0.05). These findings suggest that SiSVgp70 related AG and IC may play an important role in the course of acute leukemia and can provide useful prognostic information.

Heat production rate in polymorphonuclear granulocytes from patients with acute myelogenous leukaemia and healthy individuals

Heat production rate in polymorphonuclear granulocytes (PMN) from 18 AML patients and 21 healthy individuals was measured using microcalorimetry. An increased PMN heat production rate was found in most AML patients at diagnosis and during the first 6 months of remission. In 7/7 patients showing values above the normal mean level the heat production rate decreased during sequential analysis. The increased PMN heat production rate is serum dependent and leukaemic sera induced increased calorimetric values also in PMN from healthy donors. This effect was not due to heat labile complement factors.

Positive Coombs test in acute leukaemia

We present the results of the immunohaematological tests performed in an unselected group of patients with acute leukaemia at the time of diagnosis, and when possible the follow-up in remission and/or in relapse. Thirteen out of the 112 patients tested had a positive Coombs test at the time of diagnosis and, in six patients, the Coombs test became positive during remission. All the 19 positive Coombs test were of the complement type with, in 11 cases, an anti-I antibody eluted from the patient's RBC. There was no relationship between the FAB morphologic subtype, the presence of other immune abnormalities, the course of the leukaemia and the immunohaematological abnormalities. Several hypotheses on the possible relationships between the acute leukaemias and the immunohaematological abnormalities are discussed.

Adult acute nonlymphocytic leukemia

Chemotherapy of adults with acute nonlymphocytic leukemia has improved in recent years, yielding complete remissions in 65 per cent and cure in 10 to 15 per cent of all treated patients. Allogeneic bone marrow transplantation cures approximately one half of eligible young patients who gain an initial remission with chemotherapy. Autologous bone marrow transplantation may ultimately prove to be of value for the large numbers of patients who are over 40 years of age or who lack histocompatible siblings. Current investigative approaches in all these areas, based on insights into the pathophysiology of disease discussed in this article, should enhance the outcome for affected patients in the next decade.

Effects of tumor growth on interleukins and circulating immune complexes. Mechanisms of immune unresponsiveness

This study delineates the temporal relationship between immune complex formation and tumor growth, and provides one possible explanation for host immunosuppression during tumor growth. The authors have studied serial circulating immune complex (CIC) levels and interleukin (IL) elaboration by peripheral blood cells (IL-1 production by adherent mononuclear cells [AMC]; and IL-2 generation by peripheral blood mononuclear cells [PBMC]) during the growth of syngeneic tumor isografts in an inbred rat model. Male Wistar/Furth (W/Fu) rats were injected, subcutaneously (SC) with 2 X 10(6) W163 ( a dimethylhydrazine [DMH]-induced colon adenocarcinoma) cells into their hind limbs. Serial CIC levels, (measured by the antigen nonspecific polyethylene glycol turbidity assay) and IL-1 and IL-2 production were measured before isografting and weekly thereafter. Progressive local tumor growth occurred for 3 weeks followed by regional lymph node metastases during the fourth week. During local tumor growth, there was a progressive rise in CIC levels (123% rise compared with baseline value; P less than 0.05) which correlated with a fall in both IL-1 and IL-2 generation (r = -0.768). At the time of regional metastasis, the mean CIC levels declined, and there was a further significant decrease in IL production (IL-1 = 0.9% and IL-2 = 10% of controls in tumor bearers). These results show that progressive tumor growth results in decreased IL production by host PBC, and suggest that CIC may be involved in regulating IL generation.

Decreased responsiveness to immune complexes of granulocytes from patients with acute leukemia in remission demonstrated by microcalorimetry

Functional activity of granulocytes from healthy individuals and from patients with acute leukemia in remission was studied. The increase of heat production rate (metabolic activity) after stimulation of the blood cells with in vitro formed immune complexes was measured by microcalorimeters of heat conduction type. It was demonstrated that increased heat production rate after exposure to immune complexes was significantly lower (p less than 0.0005) in 9 patients with acute leukemia with a remission duration of less than 6 months than in 25 healthy volunteers.

Extracellular cytolysis by leukaemic blast cells

Leukaemic blast cells from 20 patients with acute leukaemia were examined for their capacity to mediate cytotoxicity against ox red blood cells in the presence of phorbol myristate acetate (PMA), a system widely employed as an in vitro model of tissue damage by metabolically activated mature phagocytes. Blasts from certain patients with myelomonocytic and monocytic leukaemia behaved like efficient killer cells. Conversely, leukaemic myeloblasts and promyelocytes as well as leukaemic lymphoblasts were ineffective. Blast cells capable of inducing the target cell lysis were also capable of mounting an oxidative respiratory burst upon challenge with PMA, as detected by the superoxide anion release. N-ethyl-maleimide, superoxide dismutase and catalase completely inhibited the cytotoxicity by monocytoid blast cells, suggesting the involvement of oxygen reactive products in the lethal hit itself. The cytolytic potential of blasts committed to monocytic differentiation might be an additional factor contributing to the tissue damage in a subpopulation of leukaemic patients.

Nature of antigens and antibodies in immune complexes isolated by staphylococcal protein A from plasma of melanoma patients

Immune complexes (IC) were isolated from plasma of melanoma patients by absorption to staphylococcal protein A and subsequent elution with MgCl2. The isolated ICs were purified by precipitation with polyethylene glycol and sucrose density gradient ultracentrifugation after radioiodination with 125I. The purified ICs were dissociated and radiolabeled antigen/antibody components were separated by ultracentrifugation at low pH (2.6). Under these conditions, about 72% radioactivity of the purified IC remained in the light-density region as a wide band. After neutralization, 26%-60% radioactivity in the region of 5S sedimentation bound to immobilized autologous immunoglobulins, as opposed to a maximum of 23% to immobilized immunoglobulins from human normal serum. Significant levels (73%-77%) of radioactivity in 7S region bound to rabbit anti-human IgG immunobeads. Immunoprecipitation of the antigen fraction by allogeneic anti-melanoma and rabbit anti-melanoma antibodies followed by SDS-polyacrylamide gel electrophoresis revealed the presence of a fetal antigen (FA) and a melanoma tumor-associated antigen (TAA). In addition, the presence of auto-antigen(s) was indicated by using autologous antibody in immunoprecipitation. Immunoglobulins (IgG) isolated from purified IC bound to cultured melanoma, sarcoma, and normal fibroblasts, although the binding to sarcoma and normal fibroblasts could be inhibited by preincubation of isolated IgG with soluble FA but not with soluble melanoma TAA. Thus, results of this investigation provide evidence that circulating IC in melanoma patients are composed of at least IgG and different antigens, and some of these antigens are produced by their tumor.