Association of large granular lymphocyte/natural killer cell proliferative disease and second hematologic malignancy

We describe the first three patients with a large granular lymphocytosis/lymphocytic leukemia and another blood malignancy. In two, a myeloproliferative disorder developed soon after the diagnosis of abnormal proliferation of large granular lymphocytes-natural killer (LGL-NK) cells, a myelodysplastic syndrome evolving to acute leukemia and a Philadelphia-positive chronic myelogenous leukemia. In these cases, LGLs expressed the phenotype of CD3+ NK and CD3- NK cells, respectively, and were clonal in the first patient as demonstrated by T-cell receptor gene rearrangement study. In the third case, a similarly clonal excess of LGLs, phenotypically CD3+ NK cells, was detected following a diagnosis of B-cell hairy-cell leukemia. Clinically, the concurrence of LGL proliferation and other leukemia did not seem to confer a worse prognosis on the patients. Although an association by chance remains a possible explanation, a common origin from an altered precursor cell for both myeloid and LGL proliferations in the first two cases is discussed, whereas in the third it might be related to the severe immune derangement frequently observed in hairy-cell leukemia.

Induction of monocyte migration by recombinant macrophage colony-stimulating factor

Human recombinant macrophage-CSF (M-CSF) induced migration across polycarbonate or nitrocellulose filters of human peripheral blood monocytes. Checkerboard analysis of M-CSF-induced migration, performed by seeding different cytokine concentrations above and below the filter, revealed that the locomotory response involved chemotaxis, though some gradient-independent augmentation of migration occurred. Polymixin B did not affect M-CSF chemotaxis and M-CSF was active on monocytes from the LPS-unresponsive mouse strain C3H/HeJ. These findings rule out a contribution of minute endotoxin contamination, below the sensitivity of the Limulus assay, in M-CSF chemotaxis. Rabbit anti-M-CSF antibodies inhibited the chemotactic activity of recombinant M-CSF, thus further indicating that the M-CSF molecule was indeed responsible for chemotaxis. M-CSF preparations encoded by 224 or 522 amino acid cDNA clones were equally effective in inducing monocyte migration. Recombinant M-CSF did not elicit a migratory response in large granular lymphocytes and in endothelial cells under conditions in which appropriate reference attractants were active. A modest stimulation of migration of polymorphonuclear leukocytes, inhibitable by antibodies, was observed at high cytokine concentrations (10 to 100 times higher than those required for monocyte locomotion). The maximal polymorphonuclear leukocytes response evoked by M-CSF was small compared to that evoked by reference chemoattractants or to that evoked by the same cytokine in monocytes. Hence, M-CSF is a potent chemoattractant for mononuclear phagocytes and exerts its action preferentially on cells of the monocyte-macrophage lineage. M-CSF, produced locally by activated macrophages, may play a role in the selective recruitment from the blood compartment of mononuclear phagocytes to amplify resistance against certain noxious agents.

Induction of monocyte migration by recombinant macrophage colony-stimulating factor

Human recombinant macrophage-CSF (M-CSF) induced migration across polycarbonate or nitrocellulose filters of human peripheral blood monocytes. Checkerboard analysis of M-CSF-induced migration, performed by seeding different cytokine concentrations above and below the filter, revealed that the locomotory response involved chemotaxis, though some gradient-independent augmentation of migration occurred. Polymixin B did not affect M-CSF chemotaxis and M-CSF was active on monocytes from the LPS-unresponsive mouse strain C3H/HeJ. These findings rule out a contribution of minute endotoxin contamination, below the sensitivity of the Limulus assay, in M-CSF chemotaxis. Rabbit anti-M-CSF antibodies inhibited the chemotactic activity of recombinant M-CSF, thus further indicating that the M-CSF molecule was indeed responsible for chemotaxis. M-CSF preparations encoded by 224 or 522 amino acid cDNA clones were equally effective in inducing monocyte migration. Recombinant M-CSF did not elicit a migratory response in large granular lymphocytes and in endothelial cells under conditions in which appropriate reference attractants were active. A modest stimulation of migration of polymorphonuclear leukocytes, inhibitable by antibodies, was observed at high cytokine concentrations (10 to 100 times higher than those required for monocyte locomotion). The maximal polymorphonuclear leukocytes response evoked by M-CSF was small compared to that evoked by reference chemoattractants or to that evoked by the same cytokine in monocytes. Hence, M-CSF is a potent chemoattractant for mononuclear phagocytes and exerts its action preferentially on cells of the monocyte-macrophage lineage. M-CSF, produced locally by activated macrophages, may play a role in the selective recruitment from the blood compartment of mononuclear phagocytes to amplify resistance against certain noxious agents.

Investigation of chronic lymphocytosis in adults

Thirteen cases of idiopathic chronic lymphocytosis are the subject of this report. Patients showed a lymphocyte count between 4 and 15 X 10(9)/L for at least six months, marrow lymphocytosis not exceeding 25%, absence of lymphomegaly and hepatosplenomegaly, and no associated infections, immune, or neoplastic disease. Morphologic examination of smears revealed a lymphocytosis of large granular lymphocytes in five. A selected battery of polyclonal and monoclonal antisera to antigens commonly found on B-, T-, and natural killer cells allowed the identification of six cases of early B-cell chronic lymphocytic leukemia, two cases of T-cell lymphocytosis with a suppressor or helper T-cell phenotype, and five cases of large granular lymphocyte/natural killer cell proliferative disease. The results demonstrate the usefulness of combining morphologic and phenotype studies for the investigation of chronic lymphocytosis, which often appears as an early leukemia or a benign clonal proliferative disorder of lymphocyte subsets.

Independent regulation of M-CSF and G-CSF gene expression in human monocytes

The macrophage and granulocyte colony-stimulating factors, M-CSF and G-CSF, act in vitro to induce proliferation and differentiation of monocyte and granulocyte progenitor cells, respectively. We show here that both of these CSFs can be produced by stimulated human blood monocytes, but the M-CSF and G-CSF genes are independently regulated. Recombinant human interleukin-3 (IL-3) and GM-CSF primarily induce expression of the M-CSF gene and secretion of M-CSF, whereas bacterial lipopolysaccharide primarily induces expression of the G-CSF gene and secretion of G-CSF. These results suggest that under different conditions of in vitro stimulation the monocyte secretes factors that could lead selectively to either granulocyte or monocyte production.

Expression of the macrophage colony-stimulating factor and c-fms genes in human acute myeloblastic leukemia cells

Macrophage colony-stimulating factor (CSF-1; M-CSF) is a growth factor required for growth and differentiation of mononuclear phagocytes. The effects of CSF-1 are mediated through binding to specific, high-affinity surface receptors encoded by the c-fms gene. CSF-1 and c-fms gene expression was investigated in fresh human acute myeloblastic leukemic cells by Northern blot hybridization using cDNA probes. 4.0-kb CSF-1 transcripts were detected in 10 of 17 cases of acute myeloblastic leukemia (AML), while c-fms transcripts were detected in 7 of 15. Coexpression of CSF-1 and c-fms was observed in five cases, and in five other cases neither gene was expressed. In situ hybridization demonstrated that transcripts for CSF-1 were present in 70-90% of cells in each of three cases studied while c-fms mRNA was detected in 40-70% of cells. The constitutive expression of CSF-1 transcripts was associated with production of CSF-1 protein, although detectable amounts of CSF-1 were not secreted unless the cells were exposed to phorbol ester. These results demonstrate that leukemic myeloblasts from a subset of patients with AML express transcripts for both the CSF-1 and CSF-1 receptor genes, often in the same leukemic cells in vitro.

Human granulocyte-monocyte colony-stimulating factor and interleukin 3 stimulate monocyte cytotoxicity through a tumor necrosis factor-dependent mechanism

Human colony-stimulating factors (CSF) exert multiple effects on the proliferation, differentiation, and function of myeloid lineage cells. In this study, the effects of three recombinant human CSFs (granulocyte-monocyte CSF [GM-CSF], interleukin 3 [IL-3], and granulocyte CSF [G-CSF]) on antibody-independent monocyte tumoricidal activity were investigated by using WEHI 164 fibrosarcoma cells as monocyte-sensitive targets. None of the CSFs directly induced monocyte cytotoxicity, although both GM-CSF and IL-3 were found to significantly enhance monocyte killing in response to a second stimulatory event (endotoxin). No effect was seen with G-CSF. Antitumor necrosis factor antibody completely abolished CSF-enhanced monocyte cytotoxicity, which suggests that this effect was mediated through increased release of tumor necrosis factor (TNF). As previously shown for GM-CSF, IL-3 was found to induce cytoplasmic accumulation of TNF messenger RNA (mRNA) after 18 hours of exposure. These results suggest that GM-CSF and IL-3 may stimulate monocyte killing indirectly by enhancing expression of TNF mRNA, thereby leading to augmented TNF protein secretion in response to a second activation signal.

c-sis but not c-fos gene expression is lineage specific in human myeloid cells

Expression of both the c-fos and c-sis protooncogenes during myeloid differentiation has been detected in cells of the monocytic lineage. Since an increase in c-fos transcripts was not detected during dimethylsulfoxide induced HL-60 granulocytic differentiation, it was suggested that within the myeloid series c-fos gene expression might be lineage specific. In the present study, we have determined whether expression of the c-fos and c-sis genes is indeed specific for the monocytic pathway or rather common to both the granulocyte and monocyte pathways. C-fos and c-sis gene expression was analyzed in freshly isolated human granulocytes and monocytes, in human HL-60 promyelocytic leukemia cells induced to differentiate along the granulocytic or monocytic pathway, in myeloblasts from five patients with the M1 or M2 subtype of acute myeloblastic leukemia (AML) and in blasts from six patients with M4 myelomonocytic leukemia. The level of c-fos mRNA was fifteen times higher in granulocytes as compared with monocytes. An increase in c-fos expression was also found in HL-60 cells differentiated along the granulocytic pathway after exposure to hypoxanthine, hexamethylene bisacetamide, and the combination of retinoic acid and dibutyryl adenosine 3'5' cyclic monophosphate. Three of 5 M1 and M2 leukemic myeloblast preparations depleted of lymphoid and monocytic cells and all six M4 leukemic cells expressed c-fos transcripts. In contrast, c-sis gene transcripts were detectable in monocytes and during drug induced monocytic differentiation of the HL-60 cells but not in granulocytes during granulocytic differentiation of the HL-60 cells or in AML samples. Thus, in the myeloid series, c-sis gene expression is lineage specific while expression of the c-fos gene is found in both lineages and may be related to metabolic pathways common to both granulocytes and monocytes.

T cell receptor (alpha, beta, gamma) gene rearrangements and expression in normal and leukemic large granular lymphocytes/natural killer cells

The large granular lymphocyte (LGL) population, which effects a natural killer (NK) function, consists of cells whose lineage derivation has not been clearly established on the basis of phenotypic and functional properties. To clarify the relationship of LGL/NK cells to T cells we studied patterns of rearrangement and expression of the T cell receptor (Ti) genes alpha, beta, and gamma in normal human LGLs; in CD8+, CD8-, Mol+, and Mol- LGL subsets; and in 17 cases of leukemic LGL proliferations (T gamma LPD). T alpha, T beta, and T gamma genes were not expressed, nor were T beta and T gamma genes rearranged in normal LGLs or LGL subsets. The T gamma LPD were divided into two groups. One group (15/17 cases) was characterized as CD3+ and displayed Ti gene rearrangements. Seven of these cases were reactive with monoclonal antibody WT31, which suggested expression of an alpha/beta heterodimer on the cell surface. The other group (2/17 cases) was CD3- with unrearranged Ti genes. These results indicate that the normal LGL/NK population is homogeneous and distinct from the normal T cell population because it does not express, and as a result, cannot effect its immune function through the T cell receptor molecules. Conversely, T gamma LPDs represent a heterogeneous group of lymphoproliferative diseases within which the CD3-, Ti- cases most likely represent the neoplastic counterpart of normal LGL cells. The more frequent CD3+ cases may be related to recently described NK-like T cells. The observations that normal LGLs maintain germline T gamma genes and that many CD3+ T gamma LPD display an alpha/beta heterodimer suggest that a T gamma-containing receptor may not be necessary for NK or NK-like cytotoxicity.

T-cell receptor gene rearrangements and expression in normal human large granular lymphocytes (LGL) and their pathological expansions

The lineage to which normal large granular lymphocytes/natural killer (LGL/NK) cells belong is controversial; in fact they share some surface markers and functional activities with monocytes, but also with T lymphocytes. The relationship of LGL to the T cell lineage by analysis with the T cell receptor (T-rec) gene has been investigated. Pure preparations of human LGL and their CD11(+) CD8(-) and CD11(-) CD8(+) subsets had the Tβ gene in its unrearranged germline configuration. Expression of Tα and Tβ genes was not detectable. The organization of Tγ gene, which is of particular importance because it occurs early in T cell ontogeny, was also found in its germline configuration.A rare type of lymphoproliferative disorder, termed Tγ-LPD, is characterized by expansion of cells very similar to LGL for morphology, phenotype, and functional activity. Of 17 patients with Tγ-LPD studied for T-rec rearrangement, 15 displayed rearrangement of Tβ and Tγ loci and were CD3+ (14/15 had monoclonal rearrangement), while 2 cases were in germline configuration and were CD3-. Similarly to very small subsets of CD3+ LGL recently described, most Tγ-LPD cases are CD3+ and have T-rec genes rearranged. These data suggest that either a subset of LGL or a particular step of differentiation may be related to the T cell lineage; they also demonstrate that, in contrast to previous views, most TγLPD are monoclonal, presumably neoplastic, lymphoproliferative disorders.

Secretion of interleukin-1 by acute myeloblastic leukemia cells in vitro induces endothelial cells to secrete colony stimulating factors

The interaction of acute myeloblastic leukemia (AML) cells with stromal cells was investigated by adding AML-conditioned media to cultures of human endothelial cells. This conditioned media contained factors that induced expression of both the granulocyte macrophage colony-stimulating factor (GM-CSF) and granulocyte CSF (G-CSF) genes and release of colony stimulating activity from endothelial cells. The conditioned media contained interleukin-1 (IL-1) bioactivity and the endothelial cell stimulatory activity was partially neutralized by anti-IL-1 antiserum. Constitutive expression of the IL-1-beta gene was detected in ten of 17 AML cases analyzed. These results suggest that the unregulated secretion of IL-1 by AML cells can induce stromal cells in vitro to overproduce CSFs. This could contribute to the unrestricted growth of AML cells.

Human granulocyte-macrophage colony-stimulating factor induces expression of the tumor necrosis factor gene by the U937 cell line and by normal human monocytes

Human granulocyte-macrophage colony-stimulating factor (GM-CSF) exerts profound effects on the proliferation, differentiation, and effector function of myeloid lineage cells. In contrast to its growth-promoting effects on normal myeloid progenitor cells, we found that GM-CSF unexpectedly inhibited the colony growth of U937 cells in agar culture. Furthermore, medium conditioned by recombinant GM-CSF(rGM-CSF)-treated U937 cells was found to exert an inhibitory effect on subsequent U937 colony growth that was partially due to the presence of tumor necrosis factor (TNF). By Northern blot analysis, rGM-CSF was shown to induce expression of the TNF gene in U937 cells and in T-lymphocyte-depleted, monocyte-enriched peripheral blood mononuclear cells. Furthermore, rGM-CSF was observed to significantly enhance TNF secretion by monocytes stimulated with endotoxin and phorbol myristate acetate (PMA). These data suggest that some of the biological effects of GM-CSF may be amplified through the release of monokines such as TNF.

Expression of the M-CSF (CSF-1) gene by human monocytes

Monocyte colony-stimulating factor (M-CSF, CSF-1) is a macrophage lineage-specific growth factor. Northern blot analysis using a human M-CSF cDNA probe and a specific bioassay for human M-CSF were used to investigate the cellular sources of M-CSF. Expression of the M-CSF gene was induced in blood mononuclear cells stimulated by phorbol myristate acetate (PMA) or gamma-interferon. When mononuclear cells were fractionated into highly purified populations of T cells and monocytes, M-CSF transcripts were detected predominantly in monocytes. Further, monocytes stimulated with PMA released an M-CSF-like activity. These results demonstrate that M-CSF can be produced by activated cells of the macrophage lineage.

Interferon-gamma induces expression of the interleukin 2 receptor gene in human monocytes

Interferon-gamma induces surface expression of interleukin 2 (IL2) receptors on human monocytes and the monocytic cell line U937. Freshly prepared peripheral blood monocytes and U937 cells were found to lack detectable IL 2 mRNA, but exposure of these cells to interferon-gamma induced IL 2 receptor message at 6 h of culture. At least two IL 2 receptor transcripts were detected (3.5 and 1.5 kb) in both monocytes and U937 cells, similar in size to IL 2 receptor transcripts in activated T cells. These results show that interferon-gamma induces expression of the monocyte IL 2 receptor gene.

Large granular lymphocyte/natural killer cell proliferative disease: clinical and laboratory heterogeneity

6 patients with a chronic, clinically heterogeneous proliferative disorder of the large granular lymphocytes (LGL) were investigated. In each case the majority of peripheral blood lymphocytes reacted with HNK-1, OKT3 and T11 monoclonal antibodies, whereas morphology and other immunological features varied from case to case. 2 cases were of particular interest. 1 patient had an expansion of HNK-1 stained, large agranular rather than granular lymphocytes; another patient's LGL simultaneously expressed HNK-1, OKT4 and T8 antigens. The heterogeneous features of these abnormally expanded cell populations are similar to those of the normal cell subsets from which they are likely to have originated.

Induction of monocyte-macrophage procoagulant activity by transformed cell lines

Human peripheral blood monocytes and mature macrophages were found to produce significant procoagulant activity (PCA), identified as tissue factor, on exposure to a variety of human (K562, HL60, Raji) and murine (TU5, NS-1) transformed cell lines. The monocyte procoagulant response was vigorous, generating PCA to a level nearly comparable to the response to endotoxin, a known stimulant for monocyte PCA. The response was rapid and could be fully elicited, in a dose-dependent fashion, within 4 hr with HL60 and Raji cell lines and within 14 hr with K562, TU5, and NS-1 cells. The monocyte PCA-inducing activity was found to reside in the membrane fraction of transformed cells. Other transformed human (Laz 509, Laz 221, Laz 156, U937, CEM) and murine (L1210, P815, TLX9, WEHI 164) cell lines had little, if any, activity. The induction of monocyte PCA by transformed cells most probably was not due to an allogeneic signal, as 1) the K562 and HL60 cell lines were potent PCA inducers despite the lack of class II histocompatibility antigen expression, whereas Laz 156, which did express HLA antigens, was ineffective; 2) mouse peritoneal macrophages responded with the production of strong PCA to the syngeneic transformed cell lines TU5 and NS-1. The monocyte-macrophage procoagulant response to transformed cell lines appeared to be independent of T lymphocytes. Indeed, monocytes purified on the basis of reactivity with monoclonal antibody Mo2 and sorting or depleted of contaminating T cells by anti-T3 antibody and complement responded similarly to conventional monocyte preparations. The production of tissue factor by monocyte-macrophages in response to exposure to some tumor cells may represent a mechanism whereby blood coagulation is activated in malignancy.

Induction of monocyte-macrophage procoagulant activity by transformed cell lines

Human peripheral blood monocytes and mature macrophages were found to produce significant procoagulant activity (PCA), identified as tissue factor, on exposure to a variety of human (K562, HL60, Raji) and murine (TU5, NS-1) transformed cell lines. The monocyte procoagulant response was vigorous, generating PCA to a level nearly comparable to the response to endotoxin, a known stimulant for monocyte PCA. The response was rapid and could be fully elicited, in a dose-dependent fashion, within 4 hr with HL60 and Raji cell lines and within 14 hr with K562, TU5, and NS-1 cells. The monocyte PCA-inducing activity was found to reside in the membrane fraction of transformed cells. Other transformed human (Laz 509, Laz 221, Laz 156, U937, CEM) and murine (L1210, P815, TLX9, WEHI 164) cell lines had little, if any, activity. The induction of monocyte PCA by transformed cells most probably was not due to an allogeneic signal, as 1) the K562 and HL60 cell lines were potent PCA inducers despite the lack of class II histocompatibility antigen expression, whereas Laz 156, which did express HLA antigens, was ineffective; 2) mouse peritoneal macrophages responded with the production of strong PCA to the syngeneic transformed cell lines TU5 and NS-1. The monocyte-macrophage procoagulant response to transformed cell lines appeared to be independent of T lymphocytes. Indeed, monocytes purified on the basis of reactivity with monoclonal antibody Mo2 and sorting or depleted of contaminating T cells by anti-T3 antibody and complement responded similarly to conventional monocyte preparations. The production of tissue factor by monocyte-macrophages in response to exposure to some tumor cells may represent a mechanism whereby blood coagulation is activated in malignancy.

Lymphokine production in T gamma lymphoproliferative disorders

We have studied five patients with chronic lymphocytosis consisting of large granular lymphocytes (LGL). The increased numbers of LGL in these patients had little or no natural killer activity, mediated antibody-dependent cellular cytotoxicity, and were induced to kill tumour lines after culture for 3 days with interleukin 2 (IL-2). Patients' LGL showed considerable reactivity with HNK-1 and AB8.28 monoclonal antibodies (MoAb), whereas positivity for OKM1 and N901 was found in only two subjects, and only one patient reacted with B73.1. No appreciable reactivity has been found with anti-Tac MoAb in the four patients tested. In the absence of stimulation, the patients' LGL produced no IL-2 and only minimal amounts of IL-1 and interferon (IFN). On stimulation with lipopolysaccharides (for IL-1) or phytohaemagglutinin A (PHA) (for IL-2 and IFN), they produced IL-1 and IFN in amounts similar to those produced by normal lymphocytes, but only modest levels of IL-2. These results indicated that proliferating LGL, like normal LGL, have a secretory capacity. The lack of constitutive lymphokine production, the lack of Tac receptor expression, and the defect in IL-2 production after PHA stimulation do not support the hypothesis of an autocrine proliferation sustained by a known growth factor.

Induction of cytotoxicity by interleukin-2 in T gamma-lymphoproliferative disorders

We have studied 7 patients with T gamma-lymphoproliferative disorders, in whom 78-88% of circulating nonadherent lymphocytes had the morphology of large granular lymphocytes (LGL) as assessed by light and transmission electron microscopy. The main common features of the membrane phenotype of these LGL expansions included expression of T3, HNK-1 and AB8.28. Other monoclonal antibody-defined surface markers of LGL (OKM1, B73.1, N901) were variably expressed or absent in these patients. Patients' LGL had little or no natural killer (NK) activity but mediated antibody-dependent cellular cytotoxicity (ADCC). Exposure to interferons (type B or gamma) for 20-72 hr resulted in no appreciable induction of cytolytic activity. In contrast, culture in the presence of interleukin-2 (IL-2) for 3 days resulted in the expression of strong cytolytic activity in all the patients tested against an NK-susceptible (K562) and an NK-resistant (Daudi) target. The expression of T3 antigen, the low levels or lack of native NK activity and the induction of consistent cytotoxicity by prolonged exposure to IL-2 led us to suggest that the cells expanding in these subjects are related to the effectors involved in lymphokine-activated killer (LAK) activity.

Immunological and genotypic analysis of human T gamma-lymphoproliferative disorders

T gamma-lymphoproliferative disorders (T gamma-LPD) are rare diseases characterized by expansion of circulating elements with resemblance to large granular lymphocytes (LGL). We have studied 12 patients with T gamma-LPD. Morphological evaluation revealed 79-88% of LGL in non-adherent peripheral blood lymphocytes as assessed by light and electron microscopy. The most common features of the membrane phenotype included expression of T3, HNK-1 and AB8.28 (anti-Fc gamma); other surface markers of LGL (OKM1, B73.1, N901) were variably expressed or absent. Patients' LGL usually had little or no NK activity, with the exception of two patients who had values comparable to those of normal donors; in addition, cell preparations from all patients mediated antibody-dependent cellular cytotoxicity. The recent availability of the T cell receptor beta chain probes allowed us to investigate the lineage and the clonality of T gamma-LPD. Of the 12 patients analyzed, 10 displayed clonal rearrangements of T beta locus and expression of the T3 antigen, whereas the two remaining cases displayed a germ-line configuration of the T beta gene and no expression of the T3 antigen. We suggest that individual T gamma-LPD cases represent the clonal expansion of cells frozen at different stages of differentiation/activation within an individual hematopoietic LGL/NK lineage. These data suggest that either a subset of LGL or a particular step of differentiation may be related to the T cell lineage.

T cell receptor beta chain gene rearrangements in lymphoproliferative disorders of large granular lymphocytes/natural killer cells

Twelve cases of T gamma LPD (lymphoproliferative disorders of Fc gamma receptor-bearing T cells) involving an expansion of large granular lymphocyte/natural killer (LGL/NK) cells were investigated for the expression of LGL/NK-associated markers and for T beta gene rearrangement. All the cases selected were classified as T gamma LPD on the basis of morphology, function, and phenotype of the circulating cells. 10 to 12 cases displayed clonal rearrangements of the T beta locus and expression of the T3 antigen, whereas the 2 remaining cases displayed the germline configuration of the T beta gene and no expression of the T3 antigen. T8, Mol, B73.1, and N901 antigens were variably expressed among both T beta+T3+ and T beta-T3- T gamma LPD cases. We suggest that individual T gamma LPD cases represent the clonal expansion of cells frozen at different stages of differentiation/activation within an individual hematopoietic LGL/NK lineage.

Production of interleukin 1 but not of procoagulant activity by large granular lymphocytes

Large granular lymphocytes (LGL) share phenotypic and functional properties with monocytes. We have investigated the production of procoagulant activity (PCA), so far attributed to cells of the monocyte-macrophage lineage, by LGL. Endotoxin triggered interleukin (IL-1) release and PCA activity by highly purified monocyte preparations. In contrast, LGL exposed to endotoxin produced IL-1 but had no PCA activity. Similarly ineffective in inducing PCA in LGL were other stimuli that either triggered monocyte PCA or stimulated the natural killer cytotoxicity of LGL. Thus, although LGL share properties with monocytes such as the capacity to produce IL-1, PCA is confined, among circulating leukocytes, to cells of the monocyte lineage.

Intraperitoneal administration of interferon beta in ovarian cancer patients

Eight patients with advanced ovarian carcinomas resistant to conventional chemotherapy were injected with interferon (IFN) beta (3 X 10(6) U) intraperitoneally twice a week. Seven subjects had ascites. Side effects included abdominal pain, fever, and constipation, but no hematologic toxicity was observed. Growth of solid tumor lesions was unaffected by IFN beta, with the possible exception of one patient who had stable disease. IFN beta intraperitoneally inhibited completely the formation of ascites in four of seven patients with effusions. Natural killer (NK) cell activity was measured in peripheral blood and tumor-associated lymphocytes (PBL and TAL). Using stringent criteria that included repeated assessment of baseline activity, a clear cut increase in NK cytotoxicity of TAL was detected in two of six subjects from whom TAL could be purified. Augmentation of NK activity was restricted to the peritoneal compartment with no effect on PBL. Studies on biologic response modifiers encompassing an analysis of events taking place at sites directly involved by neoplasia may provide an opportunity for generating information on the in situ regulation of tumor-associated host defense mechanisms in humans.

Human mononuclear phagocytes from different anatomical sites differ in their capacity to metabolize arachidonic acid

Human mononuclear phagocytes have the capacity to metabolize arachidonic acid (AA) into prostaglandins (PG) endowed with potent activities in immune responses and inflammatory processes. We have evaluated AA metabolism in human mononuclear phagocytes harvested from different anatomical sites (blood monocytes, macrophages from milk, peritoneal cavity and alveolar spaces). At thin layer radiochromatography, the AA metabolites mainly present were PGE2, TxB2 and, only in bronchoalveolar macrophages, a peak comigrating with PGD2. No appreciable levels of 6-keto-PGF1 alpha were observed. These data were confirmed using specific radioimmunoassays for TxB2, PGE2 and 6-keto-PGF1 alpha. Blood monocytes and bronchoalveolar macrophages were the poorest producers of PG, with the possible exception of PGD2 in bronchoalveolar macrophages. The high amounts of TxB2 and PGE2 produced by milk macrophages could contribute to the levels of PG in human milk. Thus, human mononuclear phagocytes obtained from diverse anatomical sites are considerably heterogeneous in terms of AA metabolism.

Effect of a streptococcal preparation (OK432) on natural killer activity of tumour-associated lymphoid cells in human ovarian carcinoma and on lysis of fresh ovarian tumour cells

The streptococcal preparation OK432 was studied for its effects on natural killer (NK) activity of peripheral blood lymphocytes (PBL) from normal donors and from ovarian cancer patients, and of tumour-associated lymphocytes (TAL) from peritoneal effusions. OK432 augmented NK activity against the susceptible K562 line and induced killing of the relatively resistant Raji line. Freshly isolated ovarian carcinoma cells were relatively resistant to killing by unstimulated PBL and TAL. OK432 induced significant, though low, levels of cytotoxicity against 51Cr-labelled ovarian carcinoma cells. Augmentation of killing of fresh tumour cells by OK432 was best observed in a 20 h assay and both autologous and allogeneic targets were lysed. PBL were separated on discontinuous Percoll gradients. Unstimulated and OK432-boosted activity were enriched in the lower density fractions where large granular lymphocytes (LGL) and activity against K562 were found. Thus, OK432 augments NK activity of PBL and TAL in human ovarian carcinomas and induces low, but significant, levels of killing of fresh tumour cells. Effector cells involved in killing of fresh ovarian tumours copurify with LGL on discontinuous gradients of Percoll.