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Sixteen proteins were demonstrated by crossed immunoelectrophoresis (CIE) of Triton X-100 solubilized megakaryoblasts against a rabbit antiserum. One of these reacted with a recently developed monoclonal antibody (SA-1) prepared by immunization with cells from a patient with megakaryoblastic leukemia. Leukemic cells from 8/15 patients with AML stained brightly for this antigen by indirect immunofluorescence. The antiserum also stained a minor subpopulation of myelo-monocytic cells in blood and bone-marrow of healthy individuals, but not lymphoblasts from 5 patients with ALL or cells from 5 CLL patients and 4 non-Hodgkin lymphomas. The protein was shown to be amphiphilic (integral) by charge-shift CIE and hydrophobic interaction CIE with phenyl-Sepharose. It was shown not to be glycosylated by Lentil lectin affinity CIE and by Sodiumborohydride labelling. SDS-polyacrylamide gel electrophoresis of 125I (Bolton-Hunter) labelled, immunoprecipitated material demonstrated 2 bands of molecular weight 34.000 and 46.000 under reducing and non-reducing conditions.

The rapid appearance of acute respiratory distress during the course of 25 hyperleukocytic leukemias was associated with the rapid increase of the leukocytosis. The regression of the tachypnea was spectacular when treating hyperleukocytosis by exchange transfusion and chemotherapy. Blood gas studies, although blurred to some extent by in vitro blast consumption of oxygen, showed a hypoxemia with a hypo-or normocapnia. The symptoms seem to be related to the leukostasis by the mechanical obstruction of the pulmonary capillaries. This leukostasis was shown to be responsible for a septal and alveolar oedema. The high frequency of this syndrome during the course of AGL and of acute phase of CGL seems to be linked to the low deformability of the myeloblasts. In CGL at its chronic phase, CLL or even in ALL, the absence of this syndrome could be explained by the greater deformability of the circulating cells. The hyperleukocytic AGL patients which do not have this syndrome are all characterized by a stable or slowly increasing leukocytosis. Thus, this syndrome seems to characterized by hyperleukocytic granulocytic leukemias with a rapid blood leukocyte doubling rate. Treatment in such cases is an emergency.

Cells of the myeloid lineage are probably derived from a population of few hematopoietic stem cells. Normal differentiation includes changes which are identifiable by histochemistry and morphology. However, the study of the early myeloid differentiation has been difficult due to the small number of progenitor cells and their lack of distinctive features.

A murine monoclonal antibody (82H5, IgM class) has been developed that detects an antigenic determinant expressed by greater than 90% of normal granulocytes and 60-80% of light-density normal bone-marrow cells, including human pluripotential progenitors (colony-forming-unit-granulocyte, erythroid, macrophage, megakaryocyte; CFU-GEMM) and committed progenitors: granulocyte-macrophage (CFU-GM), erythroid (BFU-E), and megakaryocytic (CFU-MK). This antibody did not react with erythrocytes, monocytes, platelets, lymphocytes from normal peripheral blood, lymphoblasts from patients with acute lymphoblastic leukaemia, or with lymphoid cells lines. The 82H5-defined antigenic determinant was expressed on greater than 90% of leukaemic cells of promyelocytic, myelomonocytic and monocytic morphology, and cell lines KG.1, ML.1, HL.60, K562 and U.937. Cortical thymocytes were unreactive with 82H5. Treatment of human bone-marrow cells with granulocytic-specific monoclonal antibody 82H5 plus complement significantly inhibited colony formation (48-74%; P less than 0.05) of CFU-GEMM, CFU-GM, BFU-E, CFU-MK, whereas treatment with control monoclonal anti-Ia antibody plus complement caused 79-89% inhibition. This antibody reacted strongly with 3-fuc-NAc lactosamine when tested with a panel of synthetic carbohydrate structures. We conclude that 82H5 may be a useful probe for phenotypic analysis of leukaemic cells and investigation of haematopoiesis.

Following the extensive development of monoclonal antibodies (mAbs) to surface membrane determinants, a variety of surface molecules have been defined on lymphocytes; the expression of some of these molecules helped to define lymphocyte subsets and/or differentiation markers. More recently, some of these surface molecules have acquired a “functional” status: for many of these molecules, their “functional” qualification came as the consequence of the “functional” effects induced in absence of complement, in in vitro assays, by these specific mAbs. Many authors have restricted the qualification of Lymphocyte Functional Antigens (LFA) (1,2) to mAbs able to block CTL lysis in absence of complement. As will be shown, mAbs and therefore the molecules bearing the recognized determinants can induce a variety of agonist and/or antagonist effects on the lymphocytes, which are not restricted to cytolysis. At least, using the following in vitro assays, a number of mAbs were found to interfere with such assays as lectin stimulation, MLR, IL-2 dependent T cell growth, anti-class I or anti-class II cell mediated lympholysis and NK lysis. Other in vitro assays such as lymphokines secretion (IL-2, γ-IFN, etc …), T-B cooperation, can also be studied; we have not used the latter assays routinely. In all cases, however, the major issue raised by these data is the relevance of the observed in vitro phenomenology to in vivo physiology, and the molecular basis of its mechanism.

Recent functional studies indicate that intercellular adhesion molecule-1 (ICAM-1), recognized by monoclonal antibody (MAb) RR1/1, is a ligand for lymphocyte-associated antigen (LFA)-1 in several models of antigen-independent B- and T-cell adhesion and in cytotoxic T-cell recognition. Independent reports have identified other MAbs (LB-2 and 84H10) that inhibit LFA-1-dependent adhesion by B cells or myeloid cells. We analyzed the relationships of these three MAbs. The results show that: 1) all three MAbs inhibit LFA-1-dependent conjugate formation with particular targets and that mixes of these MAbs do not show additive inhibition; 2) LB-2 and 84H10 each inhibit the binding of the other, whereas binding of RR1/1 neither inhibits nor is inhibited by binding of LB-2 or 84H10; 3) all three MAbs bind purified 84H10 protein; and 4) binding of these three MAbs is concordant on 12 different cell types and is similarly enhanced on monocytes with activation. The simplest interpretation of these data is that a single protein, ICAM-1, is recognized by the MAbs RR1/1, LB-2, and 84H10. This finding unifies and extends previous observations; ICAM-1 functions as an adhesion molecule in a variety of leukocyte interactions, apparently as a ligand for LFA-1. Furthermore, MAb binding to either of two distinct ICAM-1 epitopes inhibits ICAM-1-dependent adhesion. Table 1 MAb Inhibition of LFA-1-Dependent Conjugate Mab HeLa U937 U266 TS2/9 MHM23 LB-2 RR1/1 84H10 84H10 + LB-2 84H10 + RR1/1 RR1/1 + LB-2 38 0 ND 2 3 ND 2 ND 24 2 2 2 1 1 4 2 27 2 23 21 23 24 21 24 Conjugate formation was measured between the cytotoxic T-cell clone 8.2 and three antigen-negative targets HeLa, U937, and U266. Enumeration of conjugates was by two-color microfluorometry as described (10,19). The results are expressed as a % of targets that end up in conjugates. All assays were done in the continuous presence of saturating concentrations of the LFA-3 MAb TS2/9(17) to isolate the LFA-1 pathway. MAbs were continuously present during the assay at 100 μg/ml purified IgG except for MHM23, the LFA-1 Mab (20) and TS2/9 which were present at 300 µg/ml of Fab fragment. ND = not determined.

The human hematopoietic stem cells, multipotential and committed, are being extensively studied with immunologic probes. Detailed characterization of antigenic phenotypes of stem cells is of major importance for further investigation of the events that separate self-renewing stem cells from their committed progenitors, as well as for the development of purification techniques that would be based on differential antigenic reactivity of the stem cells, their maturing descendants, and of neoplastic clones. No culture system has been proved to assay the true human pluripotent hematopoietic stem cell, although the mixed-colony assay described by Fauser and Messner and their colleagues (1,2) detects bi-, tri-, and multi-potential progenitor cells that may represent a developmental stage very close to the objective. The techniques most commonly used to investigate the reactivity of monoclonal antibodies with hematopoietic stem cells are: complement-dependent cytotoxicity, fluorescence-activated cell sorting, and immune adherence. All of these techniques have limitations. Moreover, alterations in membrane antigens do not necessarily indicate absolute gain or loss of an antigen: they may represent quantitative changes in the density of an antigen or, as proposed for glycolipid antigens, exposure at the cell surface (3). There is also evidence that the expression of antigens may relate to the proliferative state of the stem cell (4,5) or depend upon environmental inductive influences (6), or may be modulated by certain enzymes (7,8).

The effects of human recombinant granulocyte and granulocyte-macrophage- (G- and GM-CSF), and of purified macrophage-stimulating factors (CSF-1), were tested on populations of leukemia cells isolated from 18 patients with different types of acute myeloid leukemia. Cell proliferation and differentiation were studied by culturing the cells in suspension for 7 days in the presence of CSF or medium alone. Spontaneous cell proliferation, as assessed by tritiated thymidine uptake, was observed in 9 of the 18 cases. GM-CSF induced proliferation in seven of the nine cases without spontaneous growth and increased spontaneous proliferation in nine cases. G-CSF added alone was also found to strongly stimulate leukemic blast cell proliferation, in which a translocation involving the long arm of chromosome 17 was observed. Low levels of CSF-1 stimulation were also observed in some cases. No clear morphological modification supporting evidence of terminal differentiation was observed, whereas modulation of some cell surface antigens was detected by flow cytometry. Thus, most leukemia cells still depend on growth factors for their proliferation, GM-CSF appearing the most effective. On the other hand these factors were not able to induce terminal differentiation.

Among the first activation antigens defined on human T cells, some were thought to be T cell specific like the I1–2 receptor (1, 2) or the T200 family (2) while others were not T specific like the transferrin receptor (3) or class II antigens (4). Operationally such antigens were classified as early or late onset activation antigens (5). Depending upon their kinetics, one could further discriminate those in plateau from those back to background expression at day 7 (5).

A variety of monoclonal antibodies against differentiation antigens which appear to define antigens expressed mainly in one cell lineage have now been established. However, it has already been recognized that some of these antigens are also expressed on cells from other lineages. One of the best examples is the CALLA antigen originally described as specific for early stages of B cell differentiation and subsequently described on granulocytes and other tissues (1). Monoclonal antibodies recognizing the oligosaccharide structure alpha-fucosyl-N-acetyllactosamine (IG10, My 1, 80H5, etc.) (2) have been published originally as specific for the definition of the myeloid lineage. Thereafter it was shown by ourselves (this series, Vol. 1, Ch. 26) and others (2,3) that this structure was expressed also on cells originating in the non-myeloid pathway. On the other hand, it has been shown that leukemic cells, when tested with mAbs, could express differentiation antigens belonging to different lineages (4–6). This “lineage infidelity” can be seen as a specific pattern for leukemic differentiation, or contrarily as the counterpart of a normal stage observed only on progenitor cells (4). For the above reasons it was interesting to test the monoclonal antibodies submitted to the myeloid/stem cell Workshop and to the B cell and leukemia Workshop for their cross-reactivity with cells from other lineages.

Immunoelectron microscopy was applied to human lymphocytes exposed to purified peroxidase-conjugated anti-immunoglobulin. Indeed, detectable surface immunoglobulins are a salient feature of so-called " B " lymphocytes. On living cells, a rapid and massive internatization of the labelled membrane is observed. Prior glutaraldehyde cell fixation avoids such a phenomenon. Thus, exposure of fixed cells to conjugated anti-immunoglobulin allows the visualization of a dense and continuous specific membrane labelling. Immunoglobulin-bearing lymphocytes have a characteristic membrane surrounded with numerous microvilli. On the other hand, non-labelled lymphocytes have a smooth membrane. Intermediate forms are also noted among these extreme morphological features.

A law issued on december 22, 1976 and aimed at increasing the number of kidney transplantations in France authorizes the removal of kidneys from deceased persons of full age provided they had not expressed refusal while still alive; for decreased persons under age, removal is subject to written consent of the legal representative. In a general teaching hospital of whose than 1 000 beds, 21 kidneys donors were operated upon between January 1, 1971 and December 31, 1975 (an average of 4.2 per year). A kidney transplantation team was developed in 1976. Between January 1, 1976 and August 31, 1979, 83 kidneys donors were operated, an average of 22.6 per year. Ninety-five per cent (59/62) of the kidneys removed and transplanted in the hospital began to function (diuresis greater than 2 ml/min) within minutes of releasing the clamp, no matter how long cold ischaemia had lasted. The increase in kidney removal and transplantation may be attributed to the fact that motivation was maintained among the various units concerned (anaesthesia and intensive care, neurosurgery, neuroradiology) by sustained information and teaching.

Gamma-interferon (gamma IFN), like the phorbol ester TPA, is able to induce the differentiation of the HL 60 human promyelocytic cell line in the monocytic pathway. Morphological and serological data show a differential expression of cell surface markers upon treatment with these two inducers. It was reported that TPA treatment alters the expression of some protooncogenes, like c-myc and c-fos, involved in the induction of cell proliferation, and c-fos and c-fms (CSF.1 receptor), linked to monocytic differentiation. We have analyzed the variations in the levels of expression of these oncogenes upon gamma IFN treatment of HL 60 cells. c-myc expression was unchanged during the whole induction period. The early increase reported in c-fos expression was not observed; however, c-fos levels increased upon 24 hr of gamma IFN treatment. These results suggest either that TPA and gamma IFN act at different steps, or, alternatively, that different pathways exist in the monocytic differentiation.

K562 is a human leukemic cell line used as model of hematopoietic differentiation. A variety of differentiation-inducing agents was used in this study, and the expression of surface membrane antigens associated with specific lineages of differentiation and changes in the cytochemistry of the induced cells were monitored. Sodium butyrate, hemin, retinoic acid, dimethyl sulfoxide (DMSO), phorbol myristate acetate (PMA), and interferon induced unique alterations in the binding of monoclonal antibodies specific for erythroid, granulocytic, monocytic, and megakaryocytic lineages. Hemoglobinization, Sudan Black B, glycogen content, nonspecific esterase, alkaline phosphatase, and 5'-nucleotidase staining were also altered. K562 cells were terminally differentiated with PMA to nitroblue tetrazolium-(NBT) positive macrophages. Expression of 3-fucosyl-N-acetyl lactosamine, previously thought to be myeloid specific but found on all early hematopoietic progenitors, was modulated during differentiation to nonmyeloid lineages. Lineage infidelity was noted during functional differentiation along all hematopoietic lineages. The presence of multiple lineage surface markers and cytoplasmic characteristics in leukemic cells is not indicative of lack of potential to differentiate. K562 cells cannot be compared to any normal stage of hematopoietic differentiation, but they do have the capacity to differentiate along erythroid, macrophage, and megakaryocytic lineages.

Peroxidase conjugated antibodies were applied to cell suspensions in order to detect surface associated immunoglobulins. Cell suspensions were fixed prior to incubation with reagents, a procedure avoiding membrane alterations induced by antibodies to surface component. By immunoelectron microscopy an identification of B lymphocytes could be made with simultaneous observation of their surface architecture. Basic findings were that normal circulating human B lymphocytes had a villous surface. This relationship was not confirmed however by examinating samples from various B and T cell proliferations establishing that surface morphology is not sufficient to categorize cells in disease. Specimens from hairy cell leukemia were also examined. Despite salient surface characteristics as revealed by the present method, the categorization of cells remains unclear.

Selective growth advantage of the leukemic clone over normal populations can either result from growth factor independency or, on the opposite, from an increased cell response to haemopoietic growth factors. In order to define the relationship between growth factors and leukemic cell proliferation, we studied the growth patterns of 44 Acute Myeloid Leukemia (AML) cell samples in vitro, with or without exogenous growth factors. As spontaneous proliferation was observed in 64% of the cases, growth factor gene expression and secretion of the factor in the culture medium were studied in some of these specimens. Primary AML cells were found to express several growth factor genes: IL-lα and β, GM-CSF, CSF -1, and sometimes G-CSF and IL-6. Protein excretion in the culture supernatant was documented for GM-CSF, CSF-1 and IL-lα using specific functional assays. AML cells were shown to respond by an induction or an amplification of their proliferation to the addition of human recombinant IL-3, GM-CSF and G-CSF. The existence of an autocrine loop involving GM-CSF gene expression, excretion of the protein and inhibition by specific antibodies was demonstrated in some AML with high indexes of in vitro proliferation. These results suggest that haemopoietic growth factors play a major role in the proliferation of AML cells, since these cells are able to synthesize and to respond to the major CSF or Interleukins involved in normal haemopoiesis.

The X antigen, beta Gal(1----4)[alpha Fuc(1----3)]beta GlcNAc-R, is mostly found in epithelial cells of the digestive tract, proximal convoluted tubules of the kidney, and granulocytes. The alpha-3-L-fucosyltransferase responsible for synthesis of this antigen is normally present in the serum, but we found 2 individuals, a mother and her daughter, who lack more than 90% of the serum fucosyltransferase. They are of African origin and are both Le(a-b-). The young girl suffers from a congenital kidney anomaly: oligomeganephronic hypoplasia. Her kidney tubules are devoid of X antigen. However, her mother and herself normally possess the X antigen on granulocytes and its sialylated form on monocytes. Anephric patients showed reduced serum alpha-3-L-fucosyltransferase activity, suggesting that the kidney contributes to an important fraction of serum enzymic activity. It, therefore, appears that there are distinct genetic controls governing expression of the X antigen in different body compartments. Possibly, different alpha-3-L-fucosyltransferases could be at work in kidney and leucocytes.

The effectiveness of transfusions of frozen red cells has presently been clearly demonstrated. The authors present their technique of preparation of these cells and their experience of this material in 51 cases of ECC. The results observed plead in favour of the notion that frozen-defrosted blood, combines the advantages of washed blood, freed from all plasma and cellular contaminants of fresh blood with preservation of the oxyphoric power. Going beyond the realm of ECC, the authors think that cryopreservation of blood should be applied to the majority of indications for transfusions.

The freezing of blood permits preservation of red cells over long periods of time, several months or years. Leucocyte and platelet contamination of red cell concentrates to be frozen is negligible. The amount of the various red cell metabolites (2.3 D.P.G., A.T.P., etc.) is maintained. Washing of thawed red cells removes the remaining plasma proteins and cell residues. The freezing method employed is that of Row et al. The protector used is 28% glycerol added in equal amounts to red cell concentrate to be frozen. The blood bag is kept in liquid nitrogen at -- 196 degrees C. Thawing takes place in a water bath at 45 degrees C. Wash solution is the IBM Blood regenerator. The solution used for removing glycerol is hypertonic natrium chloride. The following parameters have been investigated: --hemoglobin level; --osmotic fragility; --the amount of 2.3 D.P.G.; --residual glycerol after thawing; and clearance of leucocytes and platelets following each step of the protocol. Preliminary data regarding these features and therapeutic efficiency of processed blood are satisfactory.

Cell-cell adhesion is essential for many immunological functions. The LFA-1 molecule, a member of a superfamily of adhesion molecules, participates in adhesion which is critical to the function of each of the three major subsets of leukocytes: lymphocytes, monocytes and granulocytes. Putative LFA-1 ligands have been identified functionally in different laboratories using three different monoclonal antibodies that inhibit LFA-1-mediated leukocyte adhesion in particular model systems; however, there may be more than one LFA-1 ligand. We have directly compared the three relevant monoclonal antibodies, and show that each binds to the same molecule, intercellular-adhesion molecule-1 (ICAM-1). Most important, B, T and myeloid cells adhere specifically to purified ICAM-1-coated surfaces; such adhesion has distinctive requirements for Mg2+ and Ca2+. This constitutes biochemical evidence that ICAM-1 functions as a ligand for LFA-1-dependent adhesion by a variety of leukocytes.

Translocation t(3;21)(q26;q22) is a rare but nonrandom event occurring in Philadelphia positive chronic myeloid leukemia. We describe five new cases (two males, three females) where t(3;21) is associated with the progression of the disease. Using FACS analysis, we confirm the myeloid type of the blast crisis. High resolution chromosomal analysis allowed us to define more precisely the chromosomal breakpoints to 3q26.2 and 21q22.2, close to the respective localizations of two genes important in cell proliferation and cancer pathogenesis: the transferrin receptor gene and the ets.2 proto-oncogene.

Thioredoxin, a ubiquitous enzyme possessing an oxidoreductase activity, has recently been cloned in human. Using in situ chromosomal hybridization with a human thioredoxin cDNA probe, we have precisely localized the thioredoxin gene on chromosome 3 at bands 3p11-p12.

A patient with non-systemic idiopathic glomerulonephritis was found to have a complete deficiency of C2, the second component of complement. The clinical course, histological findings and serological abnormalities are reported in detail. The renal disease was a mild glomerulonephritis with mesangial and subendothelial immune deposits comprising IgG, IgM and C3, increased mesangial matrix without significant cell proliferation. An immunogenetic analysis of the patient's family was carried out. It was demonstrated that the homozygous C2 deficiency was associated with heterozygotism for HLA-A, B and D. Only one of the C2 deficient genes was associated with the expected HLA-A10, B18 haplotype and the propositus was HLA-D2 negative. This report confirms the fact that non-systemic glomerulonephritis should be included in the variety of immunological disorders associated with a complement deficient state. However, C2 deficiency does not seem to be related specifically to a given histological variety of glomerulonephritis.

From February 1986 to July 1987, 87 patients who underwent an autologous or allogeneic bone marrow transplantation were randomized to receive ticarpen tobramycin or ticarpen moxalactam for their first febrile episode. Forty received ticarpen tobramycin and 47 ticarpen moxalactam. The two groups were similar according to age, sex, conditioning regimen, underlaying pathology and duration of granulocytopenia. We observed 58.6% of fever unknown origin and 37% of bacteremia. A similar number of clinical and bacteriological successes occurred in the two groups. Hepatic and renal toxicities were similar in the two groups. Vancomycin was widely used in these patients without particular justification. We conclude that the use of two beta lactam is a possible antibiotherapy in marrow transplantation where renal function should be preserved from additional toxicity.

Advances in methods of blood or plasma collection, cell separation and preservation, and new techniques for plasma or cell fractionation have made blood component therapy available in all hospitals with a transfusion service. This has emphasized the unjustified wastage of whole blood, which is in short supply, and has highlighted the preservation and quality of all blood components. There is no witchcraft in blood at all, and blood transfusion is no more and no less than substitution therapy [45].

A successfull bone marrow transplant was achieved in a case of post hepatitic aplastic anemia after cyclophosphamide immunosuppression. Caryotype analysis, erythrocytic phenotype and IgG Gm allotype demonstrated evidence of complete chimerism. Anti-thymocyte serum undoubtly was able to suppress a life threatening episode of graft versus host reaction. Severe long lasting skin lesions are now persisting 2 years after the graft.

Monoclonal antibodies (MCA) were obtained by immunizing BALB/c mice with 99% pure granulocytes from normal donors or with a whole leukocyte suspension obtained from a chronic myelogenous leukemia (CML) patient, and then fusing the mouse spleen cells with a 315-43 myeloma cell clone. Four MCA were selected and studied using ELISA, immunofluorescence, cytotoxicity assays, and FACS analysis. Antibodies 80H.1, 80H.3, and 80H.5 (from normals) and 81H.1 (from CML) detected antigens expressed on neutrophils. Antibodies 80H.1 and 80H.3 (IgG) also reacted with monocytes but not with other blood cell subsets. Antibodies 80H.5 and 81H.1 (IgM) were cytotoxic and reacted strongly with most of the cells of the neutrophil maturation sequence, i.e., myeloblasts, promyelocytes, myelocytes, and mature granulocytes. Antibodies 80H.5 and 81H.1 also inhibited CFU-GM growth stimulated by leukocyte feeder layers or placental conditioned media, but did not inhibit BFU-E and CFU-E. Antigens recognized by 80H.3, 80H.5, and 81H.1 were expressed both on a proportion of cells from HL.60, KG.1, ML.1, and K562 myeloid cell lines, and on a proportion of blast cells isolated from patients with acute myelogenous leukemia. They were not found on lymphoid cell lines or lymphoid leukemia cells. These MCA recognize either late differentiation antigens expressed on mature neutrophils and monocytes (80H.1 and 80H.3) or early differentiation antigens (80H.5 and 81H.1) specific to the granulocytic lineage. They may be useful for a better definition of those antigens specific to hematopoietic stem cells and their relationship with normal or neoplastic hematopoiesis.

A and A1 antigens have been detected on cells of the human erythrocyte series by immunoelectron microscopy. These antigens have been revealed by an indirect method involving various anti-A and anti-A1 antibodies (allo, auto, hetero-antibodies) and peroxidase-conjugated anti-immunoglobulin antibodies. Immunologic labelling has been carried out with erythrocyte or bone marrow cell suspensions which were fixed prior to incubation with reagents. Cells from various A phenotypes were examined. A and A1 antigens were visualized on maturing normoblasts, at every developmental stage. In addition cell to cell variations of the surface labelling of erythrocytes was found in normal phenotypes, suggesting the existence of several populations of cells according to antigenic load.

Induction of proliferation and differentiation in response to the addition of recombinant human granulocyte colony-stimulating factor (G-CSF) was studied by both suspension and semisolid cultures in a series of acute myeloid leukemias (AML). Induction of proliferation by G-CSF alone was observed in six of 27 cases of AML. All acute promyelocytic leukemias with the specific chromosomal translocation t(15;17) and one case of myelomonocytic leukemia with balanced chromosomal translocation involving chromosome 17 at band q12q21 were induced to proliferate strongly by the G-CSF. However, contrary to the long-term proliferative effect observed with granulocyte/macrophage colony-stimulating factor (GM-CSF), G-CSF activity can be characterized by its capability to initiate and promote the growth of responding AML cells but not to sustain long-term proliferation. Finally, no terminal differentiation was found, as assessed by morphology, cytochemistry, and cell surface marker analysis. These results indicate that G-CSF may be sufficient to provide a specific signal for induction of a transient proliferation in AML without induction of terminal differentiation. The cells with the highest response are clonal leukemia cells, all bearing a translocation involving the chromosome region 17q12q21 in which the G-CSF gene has been recently located.

The effects on the lymphocytic proliferative allogenic response of a protocol of planned blood transfusions have been studied in 12 patients with chronic renal failure. This study was prospective and the experiments were performed before kidney grafting. The results were then compared with the clinical results of the graft. These results have shown that the peak allogenic proliferation in the group of patients with good renal function was significantly decreased after transfusion. This decreased response was not observed in the groups of patients with either kidney rejection or immunisation and antibody formation. Most of the lymphocyte suspensions whose proliferation was decreased after transfusion were also capable of inhibiting the proliferation of autologous lymphocytes taken before transfusion. It is therefore legitimate to postulate that the decreased response was due to the generation of suppressor lymphocytes. This latter could be responsible for the beneficial effects of blood transfusion on kidney grafting.

Using sodium butyrate and alpha, beta, and gamma interferons as inducing agents it has been possible to demonstrate the triggering of HLA class I antigen synthesis in the K562 cell line. This cell line, widely used to study hemopoietic differentiation, does not naturally express HLA antigens. This effect was confirmed by the detection of HLA class I antigens on the cell membrane with specific monoclonal antibodies, by immuneprecipitation, and by isolation of specific HLA ABC messenger RNA, in the induced cells. No synthesis of HLA class II antigens was observed. Because leukemic cells can be considered as a model representing certain stages of normal hemopoietic differentiation, the expression of HLA antigens on K562 cells induced to differentiate could be interpreted as an event related to the process of differentiation itself. The lack of expression of DR antigens may result from a genetic defect as observed for beta 2-microglobin in Daudi cells.

A1 and A alloantigens were visualized on human erythrocytes and normoblasts by immunoelectron microscopy using peroxidase-coupled antibodies. Specimens were obtained from patients with preleukemia and associated antigen weakening, and from individuals with normal antigen values. Cells were fixed by glutaraldehyde and subsequently reacted with antibodies.

A female with chronic myeloid leukemia (XX Ph 1 +) in blast crisis (localized to pleura and lymph nodes) was treated by polychemotherapy. After reversion to the chronic phase, and allogeneic bone marrow transplantation, (BMT) was performed. Sixteen months after BMT, no sign of the disease was present (XY Ph 1-).