Complete regression of primary gastric plasmacytoma following Helicobacter pylori eradication.

We describe the first case of a primary gastric plasmacytoma stage I completely regressed following Helicobacter pylori (H.pylori) eradication. The patient, a 61-year-old man, had a long history of chronic gastritis and gastric ulcers with recurrent gastrointestinal hemorrhage. Diagnosis of H.pylori infection was based on the positive urease breath test, the elevated titers of serum anti- H.pylori antibodies, and the detection of the bacterium in gastric mucosa biopsy specimens. Diagnosis of gastric plasmacytoma was based on the findings of histopathology, immunocytochemistry and in situ hybridization. Eradication of H.pylori with antibiotics was followed by disappearance of endoscopic and histopathologic features of the gastric tumor 3 months after the completion of the treatment. No relapse has been documented 20 months after the initial diagnosis of plasmacytoma. A possible causal relationship between the tumor and the underlying H.pylori infection is discussed.

Non-Hodgkin's lymphoma in patients with systemic lupus erythematosus.

Two cases of non-Hodgkin's lymphoma (NHL) associated with systemic lupus erythematosus (SLE) are described. Patient-1 was a 65-year-old woman in whom SLE and diffuse large B-cell lymphoma were concurrently diagnosed. The patient presented with low-grade fever, butterfly rash, arthritis and generalized lymphadenopathy without splenomegaly or bone marrow involvement. Complete remission of NHL and SLE was achieved with cyclophosphamide, adriamycin, vincristine and prednisone. Patient-2 was a 56-year-old woman in whom SLE had been diagnosed 14 years earlier. The patient presented with low-grade fever, bulky splenomegaly without lymphadenopathy, IgMA paraproteinemia, and expansion of a monoclonal CD19+/CD22+ lambda-type B-cell population in both bone marrow and peripheral blood. Diagnosis of a lympho-plasmacytoid lymphoma was established histologically after splenectomy. A partial remission of the neoplasm was achieved with cyclophosphamide, vincristine and prednisone. We suggest that the development of NHLs in patients with SLE may not be coincidental and we recommend the search for NHL in cases of SLE with prominent lymphadenopathy, massive splenomegaly or expansion of a monoclonal CD19+/CD22+ B-cell population.

Splenic involvement in lymphomas. Evaluation on serial CT examinations.

PURPOSE: To prospectively evaluate changes in splenic volume (SV) on serial CT of patients with lymphoma and correlate them with other indicators of the disease process. MATERIAL AND METHODS: SV was calculated in 290 abdominal CT examinations of 58 consecutive adults with lymphoma (42 non-Hodgkin's lymphoma, 16 Hodgkin's disease). Each patient had one CT investigation before, 2 during chemotherapy and 2 post-chemotherapy. The changes in SV were correlated with clinical, laboratory and other imaging indicators of the disease process. RESULTS: Three groups of patients were identified. Group A (n=20) presented no changes in SV, showed no splenic parenchymal abnormalities and had normal SV and serum lactic dehydrogenase (S-LDH). Group B (n=25) presented a decrease in SV during treatment suggesting response to therapy. Splenic parenchymal abnormalities (n=5) and other subdiaphragmatic sites of involvement (n=20) underwent remission during treatment. Eighteen patients with high S-LDH at presentation showed normal values during therapy. Group C (n=12) showed an increase in SV post-therapy associated with manifestations of disease recurrence. The S-LDH levels were elevated in 10 patients at the same time. CONCLUSION: Quantitatively assessed splenic size on CT may serve as an indicator of splenic involvement in the course of lymphomas.

Defective natural killer cell activity of peripheral blood lymphocytes correlates with the degree of neutropenia in patients with chronic idiopathic neutropenia of adults.

Natural killer cell activity (Nka) of peripheral blood mononuclear cells (PBMCs) against K562 cell targets was assessed in 66 patients with chronic idiopathic neutropenia of adults (CINA) using the 16-h 51Cr-release assay. It was found that CINA patients exhibited significantly lower Nkr than normal subjects, which strongly correlated with the degree of neutropenia and the numbers of circulating neutrophils. Patients' NKa was increased by recombinant human interleukin-2 (rhIL-2) or recombinant human interferon-alpha (rhIFN-alpha), but the values obtained did not reach the respective NKa values found in normals. However, percentages of cytokine-induced rises of NKa did not differ statistically between patients and normal subjects. No serum inhibitors of NKa were demonstrated in our patients. CINA patients had low numbers of circulating NK cells as defined by the expression of NK-cell-related surface markers CD16, CD56, and CD57. CD16+ and CD56+, but not CD57+, cells correlated with the values of baseline NKa. The numbers of all these cell subsets correlated with the degree of neutropenia and the numbers of circulating neutrophils. Using CD56+-enriched PBL suspensions, it was shown that patients' NK cells displayed normal tumor cell binding capacity and produced in vitro normal amounts of natural killer cytotoxic factor(s) against K562 cell targets upon activation with rhIFN-alpha. Finally, percentages of perforin-expressing and granzyme B-expressing CD16+ cells did not differ statistically between patients and normal controls. Based on all these observations, we concluded that CINA patients display low NKa probably because they have low numbers of circulating NK cells. No functional abnormalities of NK cells were demonstrated. The cause and the underlying mechanisms leading to NK-cell depletion in these patients remain to be clarified.

Autocrine IL-2-dependent growth of a newly established CD3+, CD16-, CD56+, CD57+, J(H)-, TCRbeta-, TCRgamma- leukemia cell line (NOI-90).

Leukemic cells from a 45-year-old male patient with a CD3+, CD56+, CD57+, CD7+ acute lymphoblastic leukemia were cultured in vitro in the absence of any added growth factor for up to 6 years and a continuous lymphoblastoid cell line (NOI-90) was established. NOI-90 cells have the same phenotype and karyotype as initial leukemic cells. Southern blot of DNA from NOI-90 cells showed that TCRbeta, TCRgamma, and J(H) were in germ line. Two and 25% of NOI-90 cells were positive when stained with the IOT14 and 7G7/B6 moAbs, which recognize the CD25 molecule (IL-2R alpha chain); moreover, 4% and 13% of the cells were positive when stained with the TU-27 and mik beta3 moAbs which recognize the CD122 molecule (IL-2Rbeta chain). Equilibrium binding experiments with radiolabelled IL-2 revealed the presence of a small number of high affinity IL-2R on both fresh and continuously growing cells. Media conditioned by NOI-90 cells could induce proliferation of an IL-2-dependent cell line and this IL-2 activity could be detected by a sensitive immunoenzymatic assay using antibodies recognizing distinct epitopes of IL-2. Moreover, IL-2 activity could be adsorbed by immunoaffinity on anti-IL-2 polyclonal purified IgG and the retained molecule displayed a m.w. of 14.5 kDa in SDS-PAGE. In addition, IL-2 immunoreactive molecules could be revealed in the cytoplasm of the cells. Finally, IL-2 fixed on the cell membrane could be detected by indirect immunofluorescence. Although added IL-2 could not induce cell proliferation, monoclonal antibodies against CD25, CD122 and IL-2 could specifically inhibit spontaneous cell proliferation in a dose-dependent manner. NOI-90 cells failed to demonstrate any cytotoxic activity against the K-562, Raji or Daudi cells. These findings indicate that NOI-90 cells are of non-T, non-B, origin lacking NK activity but proliferate under an autocrine pathway which involves, at least partly, the IL-2/IL-2R system.

Inhibition of mitogen-induced cellular cytotoxicity by serum from patients with multiple myeloma.

Mitogen-induced cellular cytotoxicity (MICC) of peripheral blood mononuclear cells (PBMCs) against K562 cell targets was assessed in 24 patients with multiple myeloma (MM) using the 24 hours 51Cr-release assay. We found that PBMCs from MM patients exhibited normal MICC values when cells were isolated, washed and cultured in vitro in the absence of patients' serum. Patients' serum inhibited MICC of normal PBMCs stimulated by PHA. A strong positive correlation was found between percentages of inhibition and the amount of serum paraprotein in the patients studied, suggesting that paraprotein should be the main inhibitory component in this model of cytotoxicity. The possible inhibitory effect of serum paraprotein of MM patients on other types of cellular immunity remains to be elucidated.

Defective natural killer cell activity in B-cell chronic lymphocytic leukaemia is associated with impaired release of natural killer cytotoxic factor(s) but not of tumour necrosis factor-alpha.

The mechanisms accounting for the impaired natural killer cell activity (NKa) in B-cell chronic lymphocytic leukaemia (B-CLL) were investigated in 34 B-CLL patients. We found that patients with B-CLL have indeed very low NKa which may be increased in the presence of recombinant human interferon-alpha or recombinant human interleukin-2. Patients had also very low mitogen-induced cellular cytotoxicity. Their absolute numbers of peripheral blood CD16+, CD57+, CD3+, and CD8+ cells were significantly increased. Patients' NK cells had a normal tumour cell binding capacity but failed to release sufficient amounts of soluble cytolytic molecules upon stimulation with K562 cells or activation with phytohaemagglutinin (PHA). However, B-CLL NK cells released tumour necrosis factor-alpha (TNF-alpha) following stimulation with PHA. We concluded that defective NKa in B-CLL patients is probably the result of an impairment in the production and/or release of soluble cytolytic mediators, but not of TNF-alpha by NK cells. Further studies on the production and release of other cytolytic molecules, such as perforin and granzymes, as well as studies on the possible inability of NK cells to activate the apoptotic mechanisms in the target cells are in progress in our laboratory.

Evidence for involvement of activated CD8+/HLA-DR+ cells in the pathogenesis of neutropenia in patients with B-cell chronic lymphocytic leukaemia.

B-cell chronic lymphocytic leukaemia (B-CLL) is often associated with peripheral blood cytopenias resulting, in most cases, from bone marrow infiltration, hypersplenism, or circulating autoantibodies. The present study was undertaken to investigate the possible involvement of a cell-mediated suppression of granulopoiesis in these patients. We studied two groups of patients, 8 neutropenic and 26 non-neutropenic, defined by the arbitrarily taken cutoff count of 2000 neutrophils/microliters. We found that neutropenic patients had higher numbers of peripheral blood CD3+, CD8+ and CD57+ cells, and higher numbers of activated CD8+/HLA-DR+ cells than the non-neutropenic ones. A negative correlation between CD8+ cells and circulating neutrophils, and a suggested negative correlation between CD8+/HLA-DR+ cells and circulating neutrophils were noted in the patients studied. Furthermore, we investigated the capacity of immunomagnetically isolated CD8+ cells to inhibit in vitro colony formation by normal granulocyte/macrophage colony-forming units (CFU-GM) and we found that inhibition was more pronounced when CD8+ cells, added in the culture, were derived from neutropenic than from non-neutropenic patients. The degree of colony inhibition correlated with the number of circulating neutrophils and the numbers of CD8+ and CD8+/HLA-DR+ cells in the patients studied. Since tumour necrosis factor-alpha (TNF-alpha) has been reported to be involved in myelosuppression, we also investigated the capacity of isolated CD8+ cells to release this cytokine into the culture supernatant fluids, and we found that comparable amounts of TNF-alpha were produced after stimulation in both neutropenic and non-neutropenic patients. Elevated serum TNF-alpha concentrations were noted only in a number of neutropenic and non-neutropenic patients. All these data taken together provide strong evidence that a T-cell subpopulation of activated CD8+/HLA-DR+ cells may be involved in the pathogenesis of neutropenia, at least in a subset of B-CLL patients, suppressing myelopoiesis by a TNF-alpha-unrelated mechanism. Efforts to isolate this cell subpopulation by flow cytometry for further analysis and a better understanding of its effect on myelopoiesis in patients with B-CLL are in progress in our laboratory.

Solitary extramedullary plasmacytoma of the oropharynx: a rare location.

We describe a case of solitary extramedullary plasmacytoma of the oropharynx growing on the left posterior tonsillar pillar. The clinical picture was difficulty in swallowing caused from the partial obstruction of the area and bleeding from the ulcerated tumor. Lambda light chains were identified on immunohistochemical staining but they were not detected in either serum or urine (non-secreting tumor). Excisional biopsy followed by radiation therapy were used for treatment. Long-term follow up for several years is necessary in order to rule out evolution to multiple myeloma.

Impaired release of natural killer cytotoxic factor(s) by peripheral blood lymphocytes in patients with chronic LGL-proliferative disease.

BACKGROUND: Chronic LGL-proliferative disease (LGL-PD) is a clonal expansion of cells with large granular lymphocyte (LGL) morphology. In most cases, proliferating cells express both suppressor/cytolytic T-cell and natural killer (NK) cell surface markers, but other cell phenotypes may be observed. LGL-PD lymphocytes have been found to lack or show very low natural killer cell activity (NKa). The aim of the present paper is to investigate the underlying mechanisms responsible for impaired NKa in a homogeneous group of five selected LGL-PD patients with a CD3+, CD8+, CD57+ cell phenotype. RESULTS: In all patients, the expanded cell population expressed very low NKa against K562 cell targets, but this increased significantly with recombinant human interleukin-2 (rhIL-2) and phytohemagglutinin (PHA) activation. Recombinant human alpha-interferon (rhIFN-alpha) had no significant effect on NKa. Cells displayed normal tumor cell binding capacity but failed to release sufficient amounts of functionally active natural killer cytotoxic factor(s) (NKCFs) upon interaction with the NK-sensitive K562 cells targets. However, they did release soluble cytolytic molecules against K562 cells upon activation with PHA. CONCLUSIONS: Our findings provide evidence that the defective NKa in LGL-PD patients with the aforementioned phenotype is probably due, at least in part, to the inability of expanded lymphocytes to release NKCFs upon interaction with NK-sensitive cell targets. Since recognition of target cells by patient lymphocytes is not disturbed and the cells are capable of producing NKCFs upon activation with PHA, it is probable that the cause of this abnormality is located at the level of the activation signal provided by the stimulatory target cells. Studies in subcellular level are certainly needed for a more precise determination of the underlying defect.

Patients with chronic LGL-proliferative disease express high mitogen-induced cellular cytotoxicity which may be partially mediated by soluble cytolytic molecules.

Natural killer cell activity (NKa) and mitogen-induced cellular cytotoxicity (MICC) of peripheral blood mononuclear cells (PBMC) were studied in five patients with chronic LGL-proliferative disease (LGL-PD) of the CD3+, CD8+, CD57+ phenotype. Both assays were performed under the same experimental conditions except that cultures for MICC contained phytohemagglutinin (PHA) at varying concentrations. Cytotoxicity was assessed against K562 cell targets using the 18 hours 51-chromium release assay. We found that LGL-PD lymphocytes of the aforementioned phenotype express low NKa but high MICC. Furthermore, supernatants derived from patients' PMBC cultures stimulated with PHA, displayed cytolytic properties comparable to those of normal lymphocytes. The findings indicate that MICC may be mediated, at least partially, by humoral cytolytic molecules. We concluded that LGL-PD lymphocytes are unable to express natural cytotoxicity but they have not lost the cytolytic machinery necessary for the destruction of sensitive target cells.

Mechanisms accounting for the impaired natural-killer cell activity in refractory anaemia with excess of blasts.

Natural killer (NK) cells were analyzed in 38 untreated patients with refractory anaemia with excess of blasts (RAEB), using cytotoxicity assays and immunofluorescence with monoclonal antibodies. We found that patients with RAEB have normal numbers of peripheral blood and bone marrow NK cells. NK cells from RAEB patients express very low natural-killer cell activity (NKa) which may be increased significantly with recombinant alpha-interferon and recombinant interleukin-2, although it remains below the lower limit of the control range. The cells exhibit normal tumour cell binding capacity, but fail to release sufficient amounts of natural-killer cytotoxic factors (NKCFs) upon their interaction with NK-sensitive K562 cell targets or their stimulation with phytohaemagglutinin. Our results suggest that defective NKa in RAEB patients may be due, at least in part, to impaired release of functionally active NKCFs. This disturbance is probably the result of some intrinsic defect of RAEB NK cells in NKCF production, storage, and/or release. The possibility of an impairment in the activation signal provided by the stimulatory K562 cells cannot be excluded, although it seems unlikely. We postulate that this abnormality might represent a manifestation of dysplastic haemopoiesis. Further studies are certainly needed to investigate whether other defective mechanisms are also implicated in the determination of the low NKa in patients with RAEB.