Role of T-cell antigens in the cytolytic activities of large granular lymphocytes (LGLs) in patients with LGL lymphocytosis

By analyzing surface antigens and cytolytic functions of proliferating large granular lymphocytes (LGLs), three types of T cell LGL lymphocytosis were delineated. The first, most commonly encountered type exhibited CD3+4-8+16+, WT31+ phenotype, low or undetectable non- major histocompatibility complex (MHC)-restricted cytotoxicity, and moderate to strong antibody-dependent cellular cytotoxicity (ADCC) and lectin-dependent cellular cytotoxicity (LDCC). Because these LGLs carried T cell antigen receptor (Ti) recognized by WT31 monoclonal antibody (MoAb), and treatment with anti-Ti, anti-CD3 MoAbs and phytohemagglutinin elicited non-MHC-restricted cytotoxicity, they may have developed from populations of in vivo primed cytotoxic T lymphocytes with unknown antigen specificity. The second, rare type of LGL lymphocytosis exhibited CD3+4-8-16+, WT31 phenotype, and strong non- MHC-restricted, ADCC and LDCC cytotoxicities. These cells were probably derived from the lymphocytes of the same phenotype found in small numbers in normal peripheral blood. Because anti-CD3 MoAb inhibited non- MHC-restricted cytotoxicity of the LGLs, a Ti not detected by WT31 MoAb, but putatively present seemed to serve as a specific receptor for target tumor cell recognition. The third type of LGL lymphocytosis showed CD3+4+8-16+, WT31+ phenotype, and lacked cytolytic activities and parallel tubular arrays. These LGLs probably evolved from cells with the same characteristics selectively located in the germinal centers of lymphoid tissues. Taken together, in patients with LGL lymphocytosis, T cell-associated antigens expressed on LGLs were shown to be involved in the regulation of LGL-mediated cytolytic activities. In addition, studies of surface antigens and the effects of MoAbs and lectins on cytolytic activities may be useful in clarifying the normal counterpart of LGLs from which leukemic or reactively proliferating LGLs originate.     

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.     

In vitro expansion and analysis of cloned cytotoxic T cells derived from patients with chronic T gamma lymphoproliferative disorders

Patients with T gamma lymphocytosis are a heterogeneous group, clearly distinguishable from other patients with chronic T lymphoproliferative disorders and usually without proven malignancy. We have attempted in vitro cloning of lymphocytes from three patients with an expansion of phenotypically and functionally different types of T gamma cells. One had T3+ B73.1+ T4 T8+ OKM1+ T gamma cells exerting antibody-dependent cellular cytotoxicity (ADCC) and natural killer (NK) cell cytotoxicity; another had T3+B73.1-T4-T8+OKM1-ADCC+NK- and a third had T3-B73.1+T4-T8- OKM1+ADCC+NK+ cells. On morphological characterization, most of the mononuclear cells of these patients resembled large granular lymphocytes (LGLs). Although lymphocytes of these patients showed almost no proliferative response capacity after stimulation with mitogens, they shared the capacity to proliferate after stimulation with Epstein-Barr virus-transformed lymphoblastoid B (B-LCL) feeder cells. Stable clones were established by this procedure. Clones from patient 3 exerted cytolytic activity against a broad spectrum of tumor cell lines, including fresh biopsy specimens of melanoma tumor target cells. All of these clones (termed activated killer [AK] cells) had the surface phenotype T3-, T4-, T8- or +, HNK1-, OKM1-, Lyt3+, WT1+ and showed ADCC in addition to AK cell cytotoxicity. Most of them were B73.1+ and expressed IgG-Fc receptors. They most likely belong to the T cell lineage, since they express IL2 receptors as recognized by the Tac antibody and did not bind monoclonal antibodies directed against monocytes or granulocytes. Thus lymphocytes with the functional and phenotypical characteristics of T gamma cells can be cloned and expanded in vitro from the peripheral lymphocytes of these patients by using the appropriate stimulus. Our results indicate that, of the heterogeneous population of NK cells, the T3- cells are more rapidly expanded than T3+ subsets. It is discussed whether or not our culture system might selectively induce proliferation in "normal" T cells rather than aberrant ones.     

Aggressive variant of morphologically typical T large granular lymphocyte leukemia/lymphoma lacking NK cell markers

A 46-year-old woman with a previous diagnosis of sarcoidosis presented with morphologically typical large granular lymphocyte (LGL) leukemia/lymphoma with an aggressive clinical course. Epstein-Barr virus DNA was detected in peripheral blood mononuclear cells by PCR. The phenotype was typical of the T cell lineage (CD2+ CD3+ CD5+ CD7+ CD8+ TCRalphabeta+) but with the absence of the CD16, CD56, CD57 NK cell markers. In addition, the LGLs expressed CD122 (p75) in the absence of CD25 which is characteristic of LGLs. These leukemic LGLs did not exhibit NK activity. The clonal nature of this proliferation was demonstrated by the rearrangement of the TCRgamma gene. This phenotypically unusual but morphologically typical LGL leukemia/lymphoma may represent the clonal expansion of a minor normal subset of T-LGLs which do not express any NK cell markers, probably corresponding to in vivo activated T cells.     

Epstein-Barr viral DNA in acute large granular lymphocyte (natural killer) leukemic cells.

Serologic studies in a male Caucasian presenting with an acute hepatitis-like illness, associated with an increase in peripheral blood large granular lymphocytes (LGLs), suggested a chronic or reactived Epstein-Barr virus (EBV) infection. The LGL were shown to have a natural killer (NK) cell, CD3- CD16- CD56+ CD57- phenotype and mediated strong nonspecific major histocompatability complex-unrestricted (NK) cytotoxic activity. A progressive increase in the peripheral blood LGL count was associated with a rapid deterioration, hepatic necrosis, and death. Widespread organ infiltration with LGLs suggested a malignant lymphoproliferative condition, but no lymphoid (T-cell receptor or IgH) gene rearrangement or cytogenetic marker was detected. However, molecular analysis identified EBV genomic DNA present in a single episomal form within the LGL, establishing the clonal nature of the LGL proliferation. Confirmation that the EBV had infected the leukemic LGL was obtained by in situ hybridization studies that showed EBV RNA within the LGLs. Immunoblotting of LGL protein extracts established that, of the EBV gene products, EBV nuclear antigen-1 (EBNA-1) was expressed but EBNA-2 and the latent membrane protein (LMP-1) were not detectable in the leukemic cells. These results suggest that EBV may be involved directly in LGL cell transformation, in a manner similar to EBV-associated B-cell lymphomas, although other molecular changes probably contribute to the evolution of a fully malignant leukemic clone.     

Current concepts: large granular lymphocyte leukemia

Clonal diseases of large granular lymphocyte (LGL) disorders can arise from a CD3+ T-cell lineage or from a CD3- NK-cell lineage. CD3+ LGL leukemia is the most frequent form of LGL leukemia. T-LGL leukemia usually affects elderly people. Approximately 60% of patients are symptomatic; recurrent infections secondary to chonic neutropenia, anemia, and rheumatoid arthrititis are the main clinical manifestations. The most common phenotype is CD3+, alphabeta+, CD8+, CD57+. Clonality is detected by clonal rearrangement of the T-cell receptor gene. NK-cell LGL proliferative disorders include NK LGL leukemia which is a very aggressive disease and NK chronic lymphocytosis. Serologic findings show frequent reactivity to the BA21 epitope of HTLV-I env p21e, suggesting that a cellular or retroviral protein with homology to BA21 may be important in pathogenesis of these diseases. Clonal expansion may be facilitated by IL12 and IL15 cytokines expressed by leukemic LGL, and also by a defective Fas (CD95) apoptotic pathway. Leukemic LGL constitutively express Fas and Fas-Ligand but they are resistant to Fas-induced apotosis. Neutropenia could be due to soluble Fas-Ligand which is highly secreted in the patient's sera. Clinical and molecular remission can be obtained with oral low-dose methotrexate. Leukemic LGL express a multi-drug resistance phenotype (PgP+/LRP+) that could partly explain the chemoresistance observed in aggressive cases. It is suggested that LGL leukemia can serve as a useful model of dysregulated apoptosis as an underlying mechanism for both malignancy and autoimmune disease.     

Immunological studies on Crohn's disease. V. Enumeration of circulating lymphocytes subsets using monoclonal antibodies

We found normal levels of suppressor cell activity and reduced natural killer (NK) and antibody dependent cell-mediated cytotoxicity (ADCC) activities in patients with Crohn's disease (CD). To further characterize these activities, studies were carried out using monoclonal antibodies. There were no changes in the proportion of OKT4+ (helper/inducer T cells), OKT8+ or Leu 2+ (suppressor/cytotoxic T cells) and Leu 7+ (large granular lymphocytes: LGL, NK + K cells), thereby suggesting that suppressor cell activity in CD is likely to be normal both in function and in number, and that depressed NK and ADCC activities are not due to a reduction in the number of NK or K cells but rather to functional defects. Using a double staining method, we noted a low percentage of both Leu 2 and Leu 7 positive cells in CD.     

A case of chronic lymphocytic leukemia with properties characteristic of natural killer cells

A case of chronic lymphocytic leukemia that consisted of a homogeneous population of cells that had properties similar to those described for natural killer (NK) cells is presented. These leukemic cells had a morphology of large granular lymphocytes (LGL) and receptors for sheep erythrocytes (ER) and for the Fc portion of IgG (Fc gamma-R). They expressed pan-T antigens OKT3 and Leu-4, but neither helper/inducer T- cell differentiation antigens OKT4 and Leu-3a nor cytotoxic/suppressor T-antigens OKT8 and Leu-2a. HNK 1 antigen, which can be expressed on human NK cells, could be detected on almost all leukemic cells (LGL), whereas a myeloid differentiation antigen, OKM1, which can be expressed on macrophages, granulocytes, and NK cells, was not detected. Thus, it was concluded that the leukemia cells had a characteristic profile of the surface markers: ER+, Fc gamma-R+, HNK-1+, OKT3+, Leu-4+, OKT4-, OKT8-, Leu-3a, Leu-2a, and OKM1-. Although freshly isolated leukemic cells showed no cytotoxicity on NK targets, after incubation at 37 degrees C, the cells did show a potent cytotoxicity on targets of erythroleukemic cell, T cell, and monocyte (but not B cell) origins. When the cells were incubated at 37 degrees C, interferon (IFN gamma) was spontaneously produced in the culture fluids. Treatment with anti- HNK-1 and complement completely abrogated expression of NK activity and interferon production of the patient's lymphocytes in culture. These characteristic features of surface markers and functions strongly suggest the possibility that the leukemia cells of this case are of NK cell origin. The relationship between this case and chronic lymphocytic leukemia of T-cell origin is discussed.     

T gamma-lymphoproliferative disease and related disorders in humans and experimental animals: a review of the clinical, cellular, and functional characteristics

T gamma lymphocytes are those lymphocytes that express receptors for both the Fc portion of IgG and sheep erythrocytes. A very high proportion of normal T gamma lymphocytes are large granular lymphocytes (LGL), the cell responsible for most, if not all, natural killer (NK) and antibody-dependent cell-mediated cytotoxicity (ADCC) in humans, rats, and mice. In general, these cells are large lymphocytes with prominent azurophilic granules in the cytoplasm. Recently, a group of lymphoproliferative disorders made up predominantly of T gamma lymphocytes has been described. The most common and best studied of these disorders we refer to as "chronic T gamma-lymphoproliferative disease" (T gamma-LPD). In most cases, this disease represents the abnormal expansion of LGL, which is reflected by an increase in functionally active NK or ADCC effector cells. The chronic T gamma-LPD lymphocytes are generally characterized as E- and EA-rosette positive, acid-phosphatase, and beta-glucuronidase positive and express the pan-T antigens OKT3/Leu-4, OKT11/Leu-5, the suppressor-associated antigens OKT5,8/Leu-2, and the NK-associated antigens Leu-7/HNK-1. Typically, the patients are older, predominantly males and characteristically have a lymphocytosis of predominantly T gamma lymphocytes with lymphocyte infiltration of the bone marrow and often the spleen. While chronic T gamma-LPD is not usually an aggressive disease, the patients are often neutropenic and have recurrent bacterial infections requiring antibiotic therapy. Some patients have benefited from cytotoxic chemotherapy., but most patients have not required chemotherapy. An experimental LGL leukemia in F344 rats appears morphologically, functionally, and clinically similar to the human chronic T gamma-LPD and serves as an experimental model for further examining the ontogeny and function of LGL and may be applicable for exploring new and more effective means for the treatment of patients with chronic T gamma-LPD.     

Natural killer cell-derived large granular lymphocyte lymphoma of lung developed in a patient with hypersensitivity to mosquito bites and reactivated Epstein-Barr virus infection

A 17-year-old female developed natural killer (NK) cell-derived large granular lymphocyte (LGL) lymphoma of the lung. She had a past history of hypersensitivity to mosquito bites (HMB). After an eight-year chronic, active Epstein-Barr virus (EBV) infection, she developed multiple lung lesions and pleural effusion. In the effusion, 60% of the cells were LGL. They were CD2+, 3−, 16+, 56+, 57+, 45RO+/RA + weak, and possessed strong NK activity. No rearrangement of T-cell–receptor genes was detected. From all these results, a diagnosis of NK-LGL lymphoma of the lung was made. EB virus DNA was detected in cells infiltrating the pleural effusion. The clonality of the LGLs was determined by Southern blot hybridization with the terminal repeat sequence of EB virus as a probe, and by chromosomal abnormalities. The patient died from respiratory failure. Necropsy of the lung revealed diffuse lymphoma composed of polymorphic cells with typical angiocentric lesions. Reportedly, lymphomas of NK lineage show predominantly extranodal involvement, and primary lung lesions are rare. In the pleural effusion of the present case, abnormally high levels of soluble Fas ligand, interleukin-10 and interferon γ were detected. This hypercytokinemia, reflecting the microenvironment of lymphoma cells, may play a role in the progression of the lymphoma and organ injury in the lung. Am. J. Hematol. 59:309–315, 1998. © 1998 Wiley-Liss, Inc.     

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.     

Characterization of natural killer cells cultured from human bone marrow cells

Human bone marrow (BM) cells, depleted of nylon wool-adherent cells, T cells, and natural killer (NK) cells, were cultured in medium containing recombinant interleukin 2 (rIL2). After 21 or 24 days in culture, numerous lymphoid cells with multiple azurophilic granules and a morphology similar to large granular lymphocytes (LGL) were found. Two-color analysis of surface phenotype showed many of these cells to be NKH1-positive and a limited number of cells had other NK markers such as CD16, CD2, or CD8. The CD3 antigen was not coexpressed with NKH1. The cultured BM cells were cytotoxic for K562, Daudi, and Raji cell lines. The NKH1+, CD2-, CD3-, CD16- cells were sorted and, in addition to having the LGL morphology, were found to be cytotoxic for K562 cells (NK [K562]). The generation of NK(K562) activity was significantly suppressed by 5-bromodeoxyuridine plus ultraviolet light treatment, indicating that DNA synthesis is required. These experiments suggest that the described culture conditions allow differentiation of progenitor cells, into immature, but functionally active, NK cells.     

Immunoarchitecture of the bone marrow in neutropenia: increased HNK-1 + cells define a subset of neutropenic patients

An immunoperoxidase technique was used to examine the distribution of lymphocyte subsets in bone marrow biopsies of 15 patients with neutropenia and seven non-neutropenic controls. The bone marrow of most patients and controls had similar distributions of immune effector cells characterized by a diffuse array of predominantly cytotoxic/suppressor T-cells and occasional nodular aggregates of helper T-cells. Cells displaying the natural killer cell marker HNK-1 were sparse in controls and most neutropenic patients. However, marked increases in marrow HNK-1 + cells were identified in four of the 15 patients. Three of these patients had diffuse HNK-1 + infiltrates associated with increased Leu 4+ (OKT-3+) T-cells while one had a nodular HNK-1+ infiltrate associated with small B-cell follicles. Each of these patients had clinical features similar to those described in the large granular lymphocyte (LGL) lymphocytosis (leukemia) syndrome, but only one of four demonstrated persistently increased numbers of LGLs in the peripheral blood. Thus, this study extends the association of neutropenia and increased numbers of cells with a T/NK phenotype to include patients whose bone marrow is the only demonstrable site of involvement. Since morphologic examination of the bone marrow could not identify the bone marrows with increased HNK-1+ cells, immunologic techniques are required to detect these cases.     

Acute lymphocytic leukemia having surface phenotype of CD 2 and NKH-1 with rapid clinical course]

Abnormal expansion of large granular lymphocytes (LGLs) was observed in peripheral blood and bone marrow in a 28-year-old man. He had general lymphadenopathy and splenomegaly. Surface phenotypical analysis of LGLs showed that these LGLs express CD 2, Ia and NKH-1 but not express CD 3, CD 4, CD 8 and Leu 7. Cytochemical analysis of these LGLs revealed positive acid phosphatase and beta-glucuronidase reaction but negative alpha-naphthyl acetate esterase reaction. These LGLs showed very weak NK activity against only MOLT-4 but showed no cytotoxic activity against K 562. An beta-receptor gene rearrangement of human T-cell receptor was not found by Southern blot analysis. Rapid and fetal clinical course with the results of theses analytical studies showed that this case is highly suggestive of acute leukemia of LGLs which is committed to NK cell lineage.     

Natural killing and antibody-dependent cellular cytotoxicity are independent immune functions in the Minnesota miniature swine.

Peripheral blood lymphocytes from Minnesota miniature pigs were tested for natural killing (NK) and antibody-dependent cellular cytotoxicity (ADCC) in a 2- to 4-hr 51Cr release assay against human myeloid and lymphoid tumor target cells. Adult specific pathogen-free and germfree animals exhibited normal levels of activity in both assays. In addition, the NK and ADCC activities of peripheral blood lymphocytes from colostrum-deprived newborn piglets were examined. These animals were obtained by hysterectomy and previously shown to be immunologically "virgin." We found that these newborn piglets exhibited normal ADCC but lacked NK activity. The differences in the ontogeny of the two activities suggest that they are distinct. Preliminary effector cell characterization studies suggest that: (i) NK and ADCC in the pig are physically not separable; (ii) the majority of the cytotoxic activity on a cell-per-cell basis is mediated by the non-T lymphocyte fraction; and (iii) the rosetted T cells, which account for about 60% of the total pig peripheral blood lymphocytes, have low but demonstrable cytotoxic activity as well.     

Hairy cell leukemia associated with large granular lymphocyte leukemia: immunologic and genomic study, effect of interferon treatment

The authors describe a patient who presented an association of hairy cell leukemia (HCL) and large granular lymphocyte (LGL) leukemia. An eventual relationship between these two rare entities is analyzed. Hairy cells (HCs) were present in the blood, bone marrow, and spleen. An excess of LGLs was found only in the blood and bone marrow. After splenectomy the patient received an alpha 2-interferon (alpha 2-IFN) treatment. The HCs surface phenotype was mu+delta+kappa+, CD20+, and CD25+. The LGLs consisted in CD3+, CD8+, HNK1+, WT31+ T lymphocytes. These were absent in the spleen. alpha 2-IFN treatment resulted in the disappearance of the HCs in the blood and bone marrow, whereas the LGLs remained unchanged. Before alpha 2-IFN treatment, peripheral blood cells, predominantly LGLs, exerted low cytotoxicity that increased up to a normal level after treatment. Using Southern blotting the authors studied the rearrangements of the T-cell receptor beta--chain (C beta) and gamma-chain (J gamma) genes and immunoglobulin heavy (JH)- and light (C kappa, C lambda)- chain genes. An unique JH and C kappa gene rearrangement was found in the blood and spleen, whereas C beta and J gamma gene rearrangements were present in the blood, not in the spleen. Under alpha 2-IFN treatment, the JH gene rearrangement fainted dramatically, in contrast to that of the C beta gene. The study of messenger RNA (mRNA) of the T cell receptor alpha and beta chains evidenced the 1.3-kilobase (kb) and 1.6-kb bands in the blood and their absence in the spleen. The patient was human T-cell leukemia virus (HTLV)-II negative by Southern analysis of blood and spleen cells. It is concluded that the LGL expansion was clonal and not reactive to the HCL. Although the authors cannot definitely exclude that both HC and LGL proliferations stem in a common leukemic precursor, their findings support an association of the two entities.     

Large granular lymphocytes in human peripheral blood: ultrastructural and cytochemical characterization of the granules

Large granular lymphocytes (LGL) are defined as nonadherent mononuclear cells with cytoplasmic azurophilic granules, avid receptors for the Fc portion of IgG, and cytotoxic functions (NK or ADCC activities). In the present study, the granules of LGL isolated from human peripheral blood have been analyzed by enzyme cytochemistry and electron microscopy. It had been found that: (1) in the single cells, granules at different stages of maturation could be detected: in addition, packaging of the granules took place in the proximity of the Golgi apparatus, which is similar to that seen in secretory cell types. (2) Acid phosphatase (AP) was observed within the granules and the vesicles located in the Golgi area: the Golgi apparatus identified through its thiamine pyrophosphatase-positivity was consistently negative for AP. (3) Alpha naphthyl-acetate esterase (ANAE) activity was localized in the granules as well as on the membrane of LGL and monocytes. (4) The ANAE activity of LGL was of the monocytic and not of the lymphocytic type, as shown by NaF inhibition. (5) The LGL granules, although identifiable as primary lysosomes, were not involved in the process of phagocytosis, since LGL failed consistently to ingest latex particles or opsonized red cells.     

CD3+, CD4-, CD8-, TCR alpha beta-, TCR gamma delta+ granular lymphocyte proliferative disorder without lymphocytosis and clinical symptoms

Granular lymphocyte-proliferative disorder is characterized by a proliferation of large granular lymphocytes (LGLs). It is often associated with neutropenia, rheumatoid arthritis (RA), and pure red cell aplasia (PRCA). Phenotypic analysis has demonstrated that in most cases, the LGLs show a clonal rearrangement of the TCR alpha beta rearrangement. We are reporting a patient with TCR gamma delta LGL proliferation without clinical findings and lymphocytosis. The patient showed an expansion of the CD3+, CD16+, CD56+, and CD57+ LGL populations which involved coexpression of TCR gamma delta with TCR J gamma and J delta 1 gene rearrangement. Autoimmune manifestations, including RA and PRCA, have not appeared and the results of laboratory examinations have not changed for 1 year after the diagnosis.     

Malignant clonal expansion of large granular lymphocytes with a Leu- 11+, Leu-7- surface phenotype: in vitro responsiveness of malignant cells to recombinant human interleukin 2

A 14-year-old Japanese female with neutropenia showed malignant proliferation of the large granular lymphocytes (LGLs). These LGLs were E rosette+ and Fc(IgG) receptor+ and therefore are referred to as T gamma lymphocytes. They were also Leu-11+ and OKT11+; however, they were clearly negative for Leu-7, OKT3, OKT8, OKM1, and HNK-1 antigens as well as for terminal deoxynucleotidyl transferase activity. Karyotype analysis revealed 47, XXX. The LGLs showed no rearrangement of T cell receptor C beta genes. The natural killer (NK) cell activity against K562 target cells was low, but was significantly augmented after stimulation by recombinant human interleukin 2 (IL 2) in contrast to minimal NK boosting by recombinant human gamma-interferon (gamma- IFN). Such a unique responsive ability to lymphokines was quite similar to that noted in fetal and cord blood cells. These LGLs also demonstrated a considerable increase in antibody-dependent cell- mediated cytotoxicity (ADCC) and lymphokine-activated killer (LAK) activity after a short incubation with IL 2. Although in a resting stage they showed no IL 2 receptor expression as examined by anti-Tac antibody, Tac antigen appeared after IL 2 treatment followed by a marked increase in 3H-thymidine incorporation and a remarkable production of gamma-IFN. To investigate the mechanism of neutropenia, in vitro IL 2-stimulated coculture studies of these cells with normal bone marrow cells were performed. Colony formation of myeloid progenitors (CFU-C) was significantly suppressed. In addition, the conditioned medium from IL 2-stimulated LGLs indicated a remarkable suppression of CFU-C. These results suggest that these LGLs with a Leu- 11+, Leu-7- surface phenotype might belong to a unique subset of pre-NK cells that are functionally and phenotypically similar to those represented at any early stage of human ontogeny and that they strongly express Tac antigen under the influence of IL 2 administration, followed by remarkable cell proliferation and gamma-IFN production.     

CD8+, CD57+ T cells from healthy elderly subjects suppress neutrophil development in vitro: implications for the neutropenia of Felty's and large granular lymphocyte syndromes

OBJECTIVE: To investigate the ability of CD8+,CD57+ large granular lymphocytes (LGL) from normal individuals and from Felty's syndrome (FS) or LGL syndrome patients to suppress allogeneic neutrophil precursor development. METHODS: Six FS patients, 5 LGL syndrome patients, and 13 elderly controls were studied. CD8+,CD57+ T cells were cocultured with cord blood-derived stem cells, and percentage inhibition was calculated. Recombinant chemokines and Fas-stimulating molecules were used in separate cultures to address possible mechanisms of suppression. Proliferation after stimulation with interleukin-2 (IL-2) and anti-CD3 was assessed. RESULTS: Significant (79%) suppression of colony-forming unit-granulocyte-macrophage (CFU-GM) by the CD8+,CD57+ subset was shown by 1 FS patient. None of the CD8+,CD57+ cells from LGL syndrome patients had any effect. Six of 13 controls studied showed >40% inhibition of CFU-GM, and all but 2 showed at least some suppression. The suppressive effect was not mediated by Fas/Fas ligand interactions or by the chemokines macrophage inhibitory protein 1alpha or IL-8. LGL from both patients and controls were largely CD28- and had reduced proliferative capacity. CONCLUSION: In a subset of FS patients, expansion of CD8+,CD57+ T cells in the bone marrow may be responsible for neutropenia by suppressing neutrophil precursors. This effect is also seen with normal LGL, which are likely to have an important function in neutrophil homeostasis.