Heterogeneity of large granular lymphocyte proliferations: morphological, immunological and molecular analysis in seven patients

The clinical, morphological, immunological and molecular features of seven patients with a stable picture of chronic granular lymphocytosis, observed over a period of up to 4 years, were studied. Mild splenomegaly was detected in one patient, while lymphoadenopathy and hepatomegaly were absent. Surface marker analysis showed in five patients the common membrane phenotype of granular T-cell lymphocytosis (T3+, T4-, T8+, Leu-7+); of the remaining two, one presented an unusual phenotype (T3+, T4+, T8+) and the other showed a marked positivity with the Leu-11 and M1 monoclonal antibodies, but lacked the T3, T4, T8 antigens. Three cases had a low (less than 30%) expression of the T1 antigen. Functional studies showed that the proliferative response to PHA and the NK function were reduced in four of the seven cases. Molecular analysis, performed in six cases, revealed a monoclonal rearrangement of the T-cell receptor beta-chain gene in three, a polyclonal T-cell configuration in two and a germ-line arrangement in the last. All three monoclonal cases showed a depressed NK activity and two a reduced PHA response. The results of this study document the heterogeneity of granular lymphocyte expansions and suggest that the clonal or reactive nature of these often indolent proliferations, suspected on the basis of immunologic functional studies, may be recognized at the DNA level.     

Heterogeneity of large granular lymphocyte leukemia. 2 cases

Large cell granulocytic leukemia (LCGL) or proliferative lymphocyte T gamma disease, characterized cytologically by the presence of lymphocytes with intracytoplasmic azurophil granules, raises the problem of whether or not it is monoclonal in character. However, although it may resemble a chronic lymphoid T leukemia or Felty's syndrome, it differs by the constant finding of infiltration of the splenic red pulp by large granular lymphocytes. Studies of their immunologic phenotype and functional activity produce heterogeneous results. The disease course varies considerably: the serious nature of the infections, knowledge of the physiopathologic mechanism of the neutropenia and the importance of the tumoral syndrome could represent therapeutic indications the modalities of which have still to be defined.     

Large granular lymphocyte proliferations. Clinical and pathogenic aspects

INTRODUCTION: The clinical course, biological features, and recent data on the pathogenesis of large granular lymphocyte (LGL) leukemia are reviewed. CURRENT KNOWLEDGE AND KEY POINTS: Clonal diseases of LGL disorders can arise from a CD3+, CD57+ T-cell lineage, which are the most frequent, or from a CD3-, CD56+ NK-cell lineage. The diagnosis of LGL leukemia is suspected on the basis of a persistent excess of LGL, usually with neutropenia and splenomegaly. It is assessed by immunophenotypic and molecular studies of T-cell receptor clonality (southern blot, PCR). Association with autoimmune diseases (rheumatoid arthritis, erythroblastopenia, etc.) is a main feature of chronic LGL proliferation. Questions about a viral agent (HTLV1?), facilitation of clonal expansion by cytokines (IL-12, IL-15), and the defective Fas apoptotic pathway are discussed. Treatment of symptomatic LGL proliferations is based on immunosuppressive agents (principally methotrexate and cyclophosphamide). FUTURE PROSPECT AND PROJECTS: The epidemiology, prognosis factors, therapeutics and the pathogenesis of LGL leukemia are unknown. We proposed the creation of a French register of LGL expansions to explore these different aspects.     

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.     

Clinical features of large granular lymphocyte leukemia

The spectrum of large granular lymphocyte (LGL) proliferations consists of four distinct entities: reactive/transient LGL expansion, chronic LGL lymphocytosis, classical indolent LGL leukemia, and aggressive LGL leukemia. LGL leukemias are classified as lymphoid malignancies. They are divided into CD3(+)/T-cell LGL (85% of cases) and CD3(-)/natural killer (NK) cell LGL leukemia (15% of cases). Recent progress in the comprehension of the leukemogenesis has shown a dysregulation of survival signals in leukemic cells. Identification of LGL expansion has been improved using T-cell receptor (TCR)beta/gamma polymerase chain reaction (PCR) analysis and a combination of Vbeta and killer cell immunoglobulin-like receptor (KIR)-specific monoclonal antibodies. LGL leukemias are characterized by a clonal LGL infiltration of the bone marrow, spleen, and liver. Monoclonality is recognized by phenotypic, molecular, and karyotypic analysis. T-LGL leukemias affect the elderly and display a relatively indolent behavior. Approximately 60% to 70% of patients are symptomatic: recurrent infections secondary to chronic neutropenia, anemia, and autoimmune disease such as rheumatoid arthritis are the main clinical manifestations. Long-lasting remission can be obtained with low-dose methotrexate, cyclosporine A, or cyclophosphamide. Conversely, NK LGL leukemias behave aggressively, and most patients do not respond to chemotherapy.     

T-cell large granular lymphocyte leukemia: an Asian perspective

To characterize T-cell large granular leukemia in Asia, 22 Chinese patients from a single institute were reported, together with an analysis of 88 Asian and 272 Western patients identified from the literature. In our cohort, anemia due to pure red cell aplasia (PRCA) occurred in 15/22 (68%) of cases, being the most common indication for treatment. Neutropenia was only found in 8/22 (36%) cases, and recurrent infections, the most important clinical problem in Western patients, were not observed. None of our cases presented with rheumatoid arthritis. These clinical features were consistently observed when compared with the 88 other Asian patients. Combined data from our cohort and other Asian cases showed that Asian patients, compared with Western patients, had more frequent anemia (66/110, 60% versus 113/240, 47%; p = 0.044), attributable to a much higher incidence of PRCA (52/110, 47% versus 6/143, 4%; p < 0.001). However, Western patients presented more frequently than Asian patients with neutropenia (146/235, 62% versus 33/110, 30%; p < 0.001) and splenomegaly (99/246, 40% versus 16/110, 15%; p < 0.001). Notably, Western patients were about eight to ten times more likely than Asian patients to have rheumatoid arthritis (73/272, 27% versus 4/106, 4%; p < 0.001) and recurrent infections (81/272, 30% versus 3/107, 3%; p < 0.001). These clinicopathologic differences have important implications on disease pathogenesis and treatment.     

Evaluation of splenectomy in large granular lymphocyte leukaemia

We performed splenectomy in four patients with severe neutropenia (less than 0.5 X 10(9)/l), recurrent infections, and splenomegaly associated with large granular lymphocyte leukaemia. Prior to splenectomy, elevated levels of neutrophil-reactive IgG were detected in sera of all three patients tested. In all patients, enlargement of the spleen was due to a characteristic lymphoid infiltration of red pulp cords. Splenectomy resulted in an increased neutrophil count greater than 0.5 X 10(9)/l in all patients; this response was sustained in two patients who benefited clinically by a dramatic reduction in frequency of infections. Poor clinical response was associated with elevated levels of antineutrophil antibody post-splenectomy. All four patients had an increase in number of circulating large granular lymphocytes post-splenectomy; one patient who had attained a sustained neutrophil response died of an accelerated lymphoproliferative disorder 19 months post-splenectomy. We conclude that splenectomy may be of value in correcting severe neutropenia and reducing infections in some patients with large granular lymphocyte leukaemia. However, splenectomy appeared to be of no value in treatment of the underlying lymphoproliferative disorder.     

Chromosomal abnormalities in T-cell large granular lymphocyte leukaemia: report of two cases and review of the literature

Cytogenetic information on T-cell large granular lymphocyte leukaemia (T-LGL; large granular lymphocytosis) is limited. We report two cases of T-LGL with unusual karyotypic aberrations. The first case showed a novel inv(7)(p15q22) as the sole chromosomal abnormality, while the second case showed an inv(14)(q11q32) with evidence of clonal evolution. The breakpoints 7p14-p15 and 14q11 coincide with the T-cell receptor (TCR)-gamma and TCR-alpha/TCR-delta gene loci respectively. This is the first report describing the possible involvement of T-cell receptor genes in karyotypic aberrations in T-LGL.     

The pathogenesis and treatment of large granular lymphocyte leukemia

Large granular lymphocyte (LGL) leukemia is a spectrum of rare lymphoproliferative diseases of T lymphocytes and natural killer cells. These diseases frequently present with splenomegaly, neutropenia, and autoimmune diseases like rheumatoid arthritis. LGL leukemia is more commonly of a chronic, indolent nature; however, rarely, they have an aggressive course. LGL leukemia is thought to arise from chronic antigen stimulation, which drives long-term cell survival through the activation of survival signaling pathways and suppression of pro-apoptotic signals. These include Jak-Stat, Mapk, Pi3k-Akt, sphingolipid, and IL-15/Pdgf signaling. Treatment traditionally includes immunosuppression with low dose methotrexate, cyclophosphamide, and other immunosuppressive agents; however, prospective and retrospective studies reveal very limited success. New studies surrounding Jak-Stat signaling suggest this may reveal new avenues for LGL leukemia therapeutics.     

Pregnancy improves neutropenia in T-cell large granular lymphocyte leukaemia

The effect of pregnancy on T-cell large granular lymphocyte (LGL) leukaemia has not been previously described. We retrospectively reviewed the clinical features of three patients with T-cell LGL leukaemia; each of them had one or more pregnancies during disease evolution. Pregnancy was associated with sustained improvement in neutrophil count and concurrent reduction in lymphocytosis. Neutropenia returned in the non-pregnant state in all cases. A similar effect, induced by exogenous progesterone in one patient, suggests a role for progesterone in overcoming mechanisms of neutropenia in this disease. Pregnancy thus appears to have a beneficial effect on neutrophil count in T-cell LGL leukaemia.     

Treatment of large granular lymphocyte leukemia with oral low-dose methotrexate

Morbidity and mortality in patients with T large granular lymphocyte (T- LGL) leukemia result from infections acquired during severe neutropenia. Optimum treatment for severe neutropenia remains undefined. We conducted an uncontrolled but prospective study of low- dose oral methotrexate, up to 10 mg/m2 weekly, in 10 patients with this disease. Therapeutic response was assessed by serial clinical evaluations and laboratory determinations including complete blood counts, lymphocyte phenotyping, and T-cell receptor gene rearrangement studies. A partial response was defined as a sustained increase in neutrophil count greater than 500/microL. A complete clinical remission was defined as achievement of a normal complete blood count and CD3+ LGL count. Previous prednisone treatment in eight of these patients had produced one clinical remission and four partial responses; tapering of prednisone in each of these patients resulted in recurrence of severe neutropenia. Five patients in this study received both methotrexate and tapering doses of prednisone. Complete clinical remissions on methotrexate were observed in five patients; an additional patient had a partial response. Molecular analyses of T-cell receptor gene rearrangement could not detect the abnormal clone in three of five patients achieving a complete clinical remission. Two weeks to 4 months of therapy were needed before attaining a neutrophil count greater than 500/microL. Complete and partial responses have been maintained on therapy, with a follow-up period ranging from 1.3 to 9.6 years. Low- dose oral methotrexate therapy is an effective treatment for some patients with LGL leukemia.     

Network model of survival signaling in large granular lymphocyte leukemia

T cell large granular lymphocyte (T-LGL) leukemia features a clonal expansion of antigen-primed, competent, cytotoxic T lymphocytes (CTL). To systematically understand signaling components that determine the survival of CTL in T-LGL leukemia, we constructed a T-LGL survival signaling network by integrating the signaling pathways involved in normal CTL activation and the known deregulations of survival signaling in leukemic T-LGL. This network was subsequently translated into a predictive, discrete, dynamic model. Our model suggests that the persistence of IL-15 and PDGF is sufficient to reproduce all known deregulations in leukemic T-LGL. This finding leads to the following predictions: (i) Inhibiting PDGF signaling induces apoptosis in leukemic T-LGL. (ii) Sphingosine kinase 1 and NFkappaB are essential for the long-term survival of CTL in T-LGL leukemia. (iii) NFkappaB functions downstream of PI3K and prevents apoptosis through maintaining the expression of myeloid cell leukemia sequence 1. (iv) T box expressed in T cells (T-bet) should be constitutively activated concurrently with NFkappaB activation to reproduce the leukemic T-LGL phenotype. We validated these predictions experimentally. Our study provides a model describing the signaling network involved in maintaining the long-term survival of competent CTL in humans. The model will be useful in identifying potential therapeutic targets for T-LGL leukemia and generating long-term competent CTL necessary for tumor and cancer vaccine development.     

Transformation of T-cell large granular lymphocyte leukaemia into a high-grade large T-cell lymphoma

We describe a case of T-cell large granular lymphocyte (LGL) leukaemia that transformed into a large-cell T-cell lymphoma 11 years from diagnosis. A 29-year-old asymptomatic female presented in 1989 with lymphocytosis, neutropenia and mild bone marrow infiltration. The circulating cells were LGL with a CD2+, CD3+, CD8+, CD4-, CD16+, CD56+, CD57- phenotype. In August 2000, she developed fever, a large submandibular mass and hepatosplenomegaly. Biochemistry showed abnormal liver function tests and raised lactate dehydrogenase (LDH) levels. A serological screen for Epstein-Barr virus, cytomegalovirus, human T-lymphotropic virus-I, human herpes virus (HHV)-6 and HHV-7 was negative. Histology of the mass was consistent with the diagnosis of peripheral T-cell lymphoma composed of large cells, and immunohistochemistry showed that the lymphoma cells had a phenotype identical to the mature LGL. Molecular analysis with the polymerase chain reaction (PCR) demonstrated rearrangement of the T-cell receptor (TCR) gamma-chain gene with a band of identical size in both bone marrow mature LGL and lymph node cells. The patient was treated with CHOP (cyclophosphamide, vincristine, doxorubicin and prednisolone), resulting in the disappearance of the mass and improvement of the hepatosplenomegaly, LDH and liver abnormalities. She underwent splenectomy, and spleen histology showed involvement by T-cell LGL leukaemia with no evidence of transformation. This case illustrates that transformation or Richter syndrome may occur in a minority of patients with T-cell LGL leukaemia, a disease that has a benign clinical course in most cases. This is the first case documented by molecular methods of the transformation of the pre-existing clone.     

Monoclonal large granular lymphocyte proliferation in SLE with HTLV-I seroreactivity

A 60-year-old part Aboriginal woman was observed to develop severe neutropenia and a large granular lymphocyte (LGL) proliferation five years after the diagnosis of systemic lupus erythematosus (SLE). Monoclonality of the CD3 +, CD4 -, CD8 + LGL population was confirmed using the novel approach of X-linked restriction fragment length polymorphism (RFLP) analysis. Indeterminate HTLV-I serology was present. The patient responded to steroid therapy. LGL proliferation in the setting of SLE and the use of X-linked RFLP analysis to define LGL clonality have not previously been reported. (Aust NZ J Med 1992; 22: 54–55.)     

TCR1+ large granular lymphocyte proliferation in rheumatoid arthritis

The T-lymphoproliferative syndrome is characterized by a proliferation of large granular lymphocytes (LGL). It is often associated with neutropenia, and in 30% of cases with rheumatoid arthritis (RA). Phenotypic analysis has demonstrated that in most cases of RA with T-proliferative disease, the LGL represent T cells with a clonal rearrangement of the / T cell receptor (TCR2). Here, three patients with / TCR1⁺ LGL proliferation suffering from long-standing arthritis and neutropenia are described. The first patient with RA showed an expansion of a heterogeneous CD2⁺ CD16⁺ CD56^- LGL population, of which 30% coexpressed TCR1 with V1 rearrangement. The second patient with ankylosing spondylitis and RA was suffering from proliferation of TCR1⁺ (V9^-, V1^-), CD2⁺ CD16^- CD56^- LGL with low coexpression of CD8. The third patient with RA was suffering from a proliferation of TCR1⁺ (V1⁺, V9^-) CD4^- CE8^- CD16^- CD56^- lymphocytes. On the basis of these unusual findings, the pathogenetic role of TCR1⁺ T cells in RA is discussed.     

T cell large granular lymphocyte leukemia and chronic NK lymphocytosis

Large Granular Lymphocyte Leukemia (LGLL) is a rare chronic lymphoproliferative disorder characterized by the clonal expansion of Large Granular Lymphocytes (LGLs). Among LGLL, the 2016 WHO classification recognizes two different entities, i.e. T-LGLL and the provisional entity Chronic Lymphoproliferative disorder of NK cells (CLPD-NK). In both subtypes neutropenia represents the hallmark of the disease and is frequently regarded as the leading reason to start treatment. Leukemic LGLs are characterized by the up-regulation of several pro-survival signaling pathways, the most relevant being the JAK-STAT axis, whose constitutive activation is partly explained by somatic mutations in STAT3 and STAT5b. In addiction, in the last few years, a relationship between STAT3 mutations/activation and the development of neutropenia was found. Given that backbone treatment relying on immunosuppressive agents is generally unsatisfactory, novel agents targeting the JAK/STAT pathway can represent a turning point in LGLL treatment.     

Exercise-induced CD8 lymphocytosis: a phenomenon associated with large granular lymphocyte leukaemia

This report describes a patient with a large granular lymphocyte leukaemia (CD8 + lymphoproliferative disease) and severe neutropenia (less than 0.5 x 10(9)/l) in whom exercise resulted in a marked lymphocytosis, a phenomenon which has not previously been recorded. The lymphocyte count at rest was within normal limits (2.2 x 10(9)/l), then fell to the resting level within 15 min of cessation of exercise. The peripheral blood mononuclear cells showed the morphology of large granular lymphocytes (LGL) by light and electron microscopy both at rest (30%) and to a much greater extent during exercise (70%). Immunophenotyping of these lymphocytes during exercise demonstrated that the predominant cell was CD3+, CD8+, CD57+ (Leu7)/CD4-, CD16-, CD25-. In the resting state, despite a total lymphocyte count within the normal range, surface marker studies indicated an excess of cells with the CD8+/CD57 + T cell phenotype (26%; cf. normal range less than or equal to 10%). Functional assays revealed a minimal increase in natural killer (NK) activity during exercise. T cell receptor beta chain gene rearrangement was demonstrable in the peripheral blood at rest and during exercise. Although severe neutropenia was present, the growth of normal colony forming units, granulocyte-macrophage (CFU-GM) was not inhibited by patient lymphocytes and no anti-neutrophil antibodies were demonstrated. Finally, hyposplenism has developed and the relationship of this to the LGL leukaemia is discussed. In summary, the findings demonstrated large granular lymphocyte leukaemia as the primary disorder for which the primary manifestation, apart from the neutropenia, was a marked exercise-induced lymphocytosis.     

Cytotoxic activity of enriched large granular lymphocyte populations in rheumatoid arthritis

Enriched large granular lymphocyte (LGL) populations and mononuclear cell populations from peripheral blood of rheumatoid arthritis (RA) patients and control individuals were compared for natural killer (NK) cell activity. The NK activity of the two study groups was very similar when mean values for both cell populations were analyzed. When comparing the difference between the NK activity of the mononuclear cell and LGL populations, 44% of the RA patients demonstrated less of an increase than all of the control individuals although the percentages of LGL, Leu 11+, and Leu 7+ cells were equivalent.