tacrolimus and Lymphoma--B-Cell

We report our experience in 17 pediatric orthotopic liver transplant (OLT) patients converted from cyclosporine (CsA) to FK506 for intractable acute and chronic rejection. FK506 was initiated orally at a dose of 0.3 mg/kg/day in most patients; the dose was then adjusted to achieve serum levels of 0.5-1.5 ng/ml. Azathioprine was discontinued and low-dose prednisone maintained. The median time between liver transplantation and FK506 conversion was 41 months. Patients have been treated for an average of 14.8 +/- 9.6 months. Six patients were converted for acute rejection and 11 for chronic rejection, i.e., vanishing bile duct syndrome (VBDS). After FK506 conversion, the actual patient and graft survival was 88% and 82%, respectively, in the group as a whole. Two patients died, one of chronic active hepatitis C and the other of lymphoma. Three patients, all with VBDS, did not respond to FK506 and therefore required retransplantation. The serum bilirubin is currently normal in 14 patients and the serum transaminases < 100 IU/ml in 12. The mean bilirubin pre-FK506 of patients successfully converted to FK506 was 4.2 mg/dl compared to 11.8 mg/dl in patients who failed conversion. Major complications included nephrotoxicity, neurotoxicity, and lymphoma. The mean glomerular filtration rate (GFR) of 97 +/- 29 mls/min/1.73m2 prior to FK506 conversion dropped to 51 +/- 20 mls/min/1.73m2 (p = 0.0001) after a mean of 13.6 months of FK506 therapy. Three patients have developed B-cell lymphomas; two of them responded to decreased immunosuppression and one died. We conclude that intractable liver graft rejection in children is most successfully reversed if FK506 is instituted before cholestasis becomes pronounced.(ABSTRACT TRUNCATED AT 250 WORDS)

Topics: Administration, Oral; Bilirubin; Child; Child, Preschool; Cyclosporine; Graft Rejection; Humans; Immunosuppression Therapy; Infant; Kidney; Liver; Liver Neoplasms; Liver Transplantation; Lymphoma, B-Cell; Prednisone; Tacrolimus

Posttransplantation lymphoproliferative disorder (PTLD) is a serious complication following solid organ transplantation that has been linked to Epstein-Barr virus (EBV) infection. The aim of this article was to describe a single-center experience with the multiplicity of clinical presentations of PTLD. Among 350 liver transplantations performed in 303 children, 13 survivor children displayed a histological diagnosis of PTLD (13/242 survivors; 5.4%). The age at diagnosis ranged from 12 to 258 months (median, 47), and the time from transplantation ranged from 1 to 84 months (median, 13). Ten of these children (76.9%) were EBV-naïve prior to transplantation. Fever was present in all cases. The clinical signs at presentation were anemia (92.3%), diarrhea and vomiting (69.2%), recurrent upper airway infections (38.4%), Waldeyer ring lymphoid tissue hypertrophy (23.0%), abdominal mass lesions (30.7%), massive cervical and mediastinal adenopathy (15.3%), or gastrointestinal and respiratory symptoms (30.7%). One child developed fulminant hepatic allograft failure secondary to graft involvement by PTLD. Polymorphic PTLD was diagnosed in 6 patients; 7 had the diagnosis of lymphoma. Treatment consisted of stopping immunosuppression as well as starting intravenous gancyclovir and anti-CD20 monoclonal antibody therapy. The mortality rate was 53.8%. The clinical presentation of PTLD varied from fever of unknown origin to fulminant hepatic failure. The other symptoms that may be linked to the diagnosis of PTLD are pancytopenia, tonsil and adenoid hypertrophy, cervical or mediastinal lymph node enlargement, as well as abdominal masses. Despite numerous advances, the optimal treatment approach for PTLD is not completely known and the mortality rate is still high.

Topics: Biliary Atresia; Child; Child, Preschool; Colonic Neoplasms; Cyclosporine; Drug Therapy, Combination; Epstein-Barr Virus Infections; Female; Herpesvirus 4, Human; Humans; Immunosuppressive Agents; Infant; Liver Transplantation; Lymph Nodes; Lymphoma, B-Cell; Lymphoproliferative Disorders; Male; Postoperative Complications; Prednisone; Retrospective Studies; Survivors; Tacrolimus

Calcineurin is a calcium-activated serine/threonine phosphatase critical to a number of developmental processes in the cardiovascular, nervous and immune systems. In the T-cell lineage, calcineurin activation is important for pre-T-cell receptor (TCR) signaling, TCR-mediated positive selection of thymocytes into mature T cells, and many aspects of the immune response. The critical role of calcineurin in the immune response is underscored by the fact that calcineurin inhibitors, such as cyclosporin A (CsA) and FK506, are powerful immunosuppressants in wide clinical use. We observed sustained calcineurin activation in human B- and T-cell lymphomas and in all mouse models of lymphoid malignancies analyzed. In intracellular NOTCH1 (ICN1)- and TEL-JAK2-induced T-cell lymphoblastic leukemia, two mouse models relevant to human malignancies, in vivo inhibition of calcineurin activity by CsA or FK506 induced apoptosis of leukemic cells and rapid tumor clearance, and substantially prolonged mouse survival. In contrast, ectopic expression of a constitutively activated mutant of calcineurin favored leukemia progression. Moreover, CsA treatment induced apoptosis in human lymphoma and leukemia cell lines. Thus, calcineurin activation is critical for the maintenance of the leukemic phenotype in vivo, identifying this pathway as a relevant therapeutic target in lymphoid malignancies.

Topics: Animals; Antineoplastic Agents; Calcineurin; Calcineurin Inhibitors; Cell Line, Tumor; Cyclosporine; Disease Models, Animal; Enzyme Activation; Humans; Leukemia-Lymphoma, Adult T-Cell; Lymphoma, B-Cell; Mice; Mice, Inbred C57BL; Mice, Knockout; Mice, Transgenic; Oncogene Proteins, Fusion; Receptor, Notch1; Tacrolimus

Encephalitis as the result of human herpesvirus (HHV)-6 is usually fatal when it is resistant to antiviral drugs.. We describe a patient who developed HHV-6 encephalitis after human leukocyte antigen-haploidentical transplantation using a reduced intensity regimen.. The patient developed severe disorientation, amnesia, and tremors on day 28. Magnetic resonance imaging of the brain revealed limbic encephalitis, and the cerebrospinal fluid sample was positive for only HHV-6 in polymerase chain reaction analysis. Neither ganciclovir nor foscarnet was effective. The patient recovered from the critical condition of HHV-6 encephalitis after donor lymphocyte infusion (DLI). Almost all of his symptoms resolved, polymerase chain reaction tests for HHV-6 in the cerebrospinal fluid were negative, and magnetic resonance imaging findings were normal.. This is the first report of DLI as a treatment for HHV-6 encephalitis and the first report of DLI from an human leukocyte antigen-haploidentical donor as a treatment for life-threatening viral infection.

Topics: Adult; Brain; Encephalitis, Viral; Graft vs Host Disease; Herpesvirus 6, Human; Histocompatibility Testing; HLA Antigens; Humans; Immunosuppressive Agents; Lymphocyte Transfusion; Lymphoma, B-Cell; Magnetic Resonance Imaging; Male; Roseolovirus Infections; Stem Cell Transplantation; Tacrolimus; Tissue Donors

A case of gross skeletal muscle uptake of 18F-FDG during PET is described. The clinical context of immunosuppression after heart and lung transplantation and the absence of any other known association make the former a likely etiologic factor.

Topics: Adult; Diagnosis, Differential; Drug Interactions; Female; Fever; Fluorodeoxyglucose F18; Heart-Lung Transplantation; Humans; Immunosuppressive Agents; Lymphoma, B-Cell; Muscle, Skeletal; Mycophenolic Acid; Positron-Emission Tomography; Radiography, Thoracic; Radiopharmaceuticals; Tacrolimus; Tomography, X-Ray Computed

HER2 is an attractive immunotherapeutic target for neoplastic disease because this cell surface molecule is overexpressed on a large fraction of malignant tumor cells. To directly assess therapeutic responses to targeted therapy by noninvasive in vivo imaging in small animals, human HER2-expressing ovarian carcinoma cells were genetically modified with a firefly luciferase gene, and light emission was used for visualization of tumor growth and response to therapy. This imaging approach was able to demonstrate in real-time tumor regression in a HER2 xenograft mouse model by adoptive transfer of in vitro induced and expanded cytotoxic CD8+ natural killer T (NKT) cells retargeted with a humanized bispecific antibody F(ab')(2)HER2xCD3. Immunotherapy with effector cells alone or a humanized monoclonal antibody anti-p185(HER2) (4D5-8) resulted in significant but slower reduction in tumor burden. Long-term survival of tumor xenografts correlated inversely with visible residual tumor burden. In vitro, F(ab')(2)HER2xCD3 substantially augmented cytotoxic activity of CD8+ NKT cells. By flow-sorting, CD8+ NKT cells coexpressing CD56 were found to have the highest redirected killing ability. Treatment with concanamycin A or EGTA abrogated CD8+ NKT cytotoxicity indicating that perforin is a major pathway of tumor cell lysis. In contrast, when CD8+ NKT cell were cross-linked with F(ab')(2)HER2xCD3 neither the immunosuppressants cyclosporine A and FK506, nor the increase of intracellular cyclic AMP by dibutyryl cyclic AMP were able to inhibit cytotoxicity demonstrating that signaling via the CD3 antigen changes the biological activity of non-MHC-restricted effector cells. These studies have demonstrated that CD8+ NKT cells can be successfully redirected to tumor cells using bispecific antibodies and offer a promising strategy for adoptive immunotherapy of neoplastic diseases.

Topics: Animals; Antibodies, Bispecific; CD3 Complex; CD8-Positive T-Lymphocytes; Cyclic AMP; Cyclosporine; Cytotoxicity, Immunologic; Female; Humans; Immunotherapy, Adoptive; Intercellular Adhesion Molecule-1; Killer Cells, Natural; Luminescent Measurements; Lymphocyte Function-Associated Antigen-1; Lymphoma, B-Cell; Membrane Glycoproteins; Mice; Ovarian Neoplasms; Perforin; Pore Forming Cytotoxic Proteins; Receptor, ErbB-2; Tacrolimus; Tumor Cells, Cultured; Xenograft Model Antitumor Assays

Bcl-2 protein family members are among the key regulators of the apoptosis effector phase. Therefore, we investigated the ability of synthetic peptides derived from proteins of the Bcl-2 family, namely, the NH2-terminal region of Bcl-2 (Bcl2_syn), a central domain of Bax (Bax_syn), and a central domain of Bak (Bak_syn) to interfere with the apoptotic process in LLC-PK1 cells. Apoptosis was induced by tacrolimus or lipopolysaccharide treatment, and microinjection of Bcl2_syn into stimulated LLC-PK1 cells significantly reduced the percentage of apoptotic cells detected within 4 h after the treatment. Microinjection of Bax_syn or Bax_syn, in contrast, induced apoptosis in otherwise untreated LLC-PK1 cells during the same period of time. A random sequence control peptide (Control_syn), which served as a negative control, as well as FITC-labeled dextran, which was coinjected in all experiments for visualization, were ineffective in either preventing or inducing apoptosis. These results suggest that synthetic peptides mimicking the functional domains of proteins of the Bcl-2 family are capable of regulating apoptosis when microinjected into LLC-PK1 cells in vivo. Analogs to these regulatory peptides could therefore provide valuable lead compounds in the therapeutical context.

Topics: Animals; Apoptosis; bcl-2 Homologous Antagonist-Killer Protein; bcl-2-Associated X Protein; Cytochrome c Group; Electrochemistry; Epithelial Cells; Humans; Immunosuppressive Agents; Kidney Tubules, Proximal; Lipopolysaccharides; LLC-PK1 Cells; Lymphoma, B-Cell; Membrane Proteins; Microinjections; Peptide Fragments; Protein Structure, Secondary; Proto-Oncogene Proteins; Proto-Oncogene Proteins c-bcl-2; Swine; Tacrolimus

Anetoderma is circumscribed atrophy of the skin due to a localized deficiency in elastic tissue. It can follow inflammatory skin diseases of several types, and occasionally is present in the skin around neoplasms. There are a few reports of anetoderma in the lesional skin of cutaneous lymphoma. We report on two patients who presented with multiple lesions of anetoderma and who later proved to have low-grade cutaneous B-cell lymphomas. One patient (Patient 1) is a 39-year-old man and the other patient is a 26-year-old woman who is a renal transplant recipient (Patient 2). Some biopsy specimens from the anetodermic skin of Patient 1 appeared to show an urticarial reaction, although plasma cells were present. A large nodule showed lymphoid follicles surrounded by plasmacytoid lymphocytes, with loss of elastic tissue in the adjacent dermis. The plasmacytoid cells stained overwhelmingly for lambda light chain, and staining of the urticarial lesions from this patient also showed a marked majority of lambda positive cells. Immunoglobulin heavy chain gene (IgH) rearrangements showed a dominant clonal pattern in the nodular lesion. We classified the disease in Patient 1 as marginal zone lymphoma and the disease in Patient 2 as a post-transplant lymphoproliferative disorder. Because of the intimate association of anetoderma and cutaneous B-cell lymphoproliferative disorders in these two patients, it seems possible that anetoderma could result from either a local effect of the neoplastic cells or associated inflammatory cells, especially neutrophils as in Case 1. The infiltrates of Case 1 had many interstitial neutrophils and only a few clonal plasmacytoid lymphocytes, indicating that this presentation of B-cell lymphoma can be a diagnostic pitfall. Given these two cases and similar ones in the literature, biopsy of lesional skin in anetoderma should be performed to ensure that lymphomatous infiltrates are not present. Even if plasma cells are sparse, studies to detect clonality are appropriate. Cutaneous B-cell lymphoma can be added to the list of associations of elastolysis and cutaneous lymphoma, which includes granulomatous slack skin (T-cell lymphoma) and cutis laxa (myeloma).

Topics: Adult; Atrophy; Cutis Laxa; Cyclosporine; DNA; Elastic Tissue; Female; Fluorescein-5-isothiocyanate; Gene Rearrangement, B-Lymphocyte, Heavy Chain; Herpesvirus 4, Human; Humans; Immunocompromised Host; Immunohistochemistry; In Situ Hybridization; Kidney Transplantation; Leukemia, Lymphocytic, Chronic, B-Cell; Lymphoma, B-Cell; Lymphoproliferative Disorders; Male; Polymerase Chain Reaction; RNA, Viral; Skin Neoplasms; Tacrolimus

Topics: Antineoplastic Combined Chemotherapy Protocols; Child, Preschool; Disease Progression; Female; Heart-Lung Transplantation; Humans; Immunosuppressive Agents; Lymphoma, B-Cell; Lymphoproliferative Disorders; Tacrolimus

Although tacrolimus-based immunosuppression has made intestinal transplantation feasible, the risk of the requisite chronic high-dose treatment has inhibited the widespread use of these procedures. We have examined our 1990-1997 experience to determine whether immunomodulatory strategies to improve outlook could be added to drug treatment.. Ninety-eight consecutive patients (59 children, 39 adults) with a panoply of indications received 104 allografts under tacrolimus-based immunosuppression: intestine only (n = 37); liver and intestine (n = 50); or multivisceral (n = 17). Of the last 42 patients, 20 received unmodified adjunct donor bone marrow cells; the other 22 were contemporaneous control patients.. With a mean followup of 32 +/- 26 months (range, 1-86 months), 12 recipients (3 intestine only, 9 composite grafts) are alive with good nutrition beyond the 5-year milestone. Forty-seven (48%) of the total group survive bearing grafts that provide full (91%) or partial (9%) nutrition. Actuarial patient survival at 1 and 5 years (72% and 48%, respectively) was similar with isolated intestinal and composite graft recipients, but the loss rate of grafts from rejection was highest with intestine alone. The best results were in patients between 2 and 18 years of age (68% at 5 years). Adjunct bone marrow did not significantly affect the incidence of graft rejection, B-cell lymphoma, or the rate or severity of graft-versus-host disease.. These results demonstrate that longterm rehabilitation similar to that with the other kinds of organ allografts is achievable with all three kinds of intestinal transplant procedures, that the morbidity and mortality is still too high for their widespread application, and that the liver is significantly but marginally protective of concomitantly engrafted intestine. Although none of the endpoints were markedly altered by donor leukocyte augmentation (and chimerism) with bone marrow, establishment of the safety of this adjunct procedure opens the way to further immune modulation strategies that can be added to the augmentation protocol.

Topics: Actuarial Analysis; Adjuvants, Immunologic; Adolescent; Adult; Age Factors; Bone Marrow Transplantation; Child; Child, Preschool; Feasibility Studies; Female; Follow-Up Studies; Graft Rejection; Graft Survival; Graft vs Host Disease; Humans; Immunosuppressive Agents; Incidence; Infant; Intestines; Leukocyte Transfusion; Liver Transplantation; Lymphoma, B-Cell; Male; Middle Aged; Nutritional Physiological Phenomena; Risk Factors; Safety; Survival Rate; Tacrolimus; Transplantation Chimera; Transplantation Immunology; Transplantation, Homologous; Treatment Outcome

Extravasation is a critical process for the physiological lymphocyte traffic as well as the hematogenous spread of malignant hemopoietic cells. Here we report that abrogation of calcineurin activity leads to in vitro transendothelial migration and in vivo infiltration of human lymphoma Nalm-6 cells, which are associated with the abrogation of the VLA-4/VCAM-1 mediated pathway. Rapamycin, which can antagonize FK506 but not CsA to inhibit calcineurin, abrogates FK-506 mediated but not CsA mediated inhibition of in vitro transendothelial migration. FK506 may exert its potent immunosuppressive action partly by inhibiting VLA-4/VCAM-1 mediated transendothelial migration or insinuation of lymphoid cells to tissues.

Topics: Animals; B-Lymphocytes; Bone Marrow Cells; Calcineurin; Cell Adhesion; Cell Movement; Central Nervous System; Endothelium; Humans; Immunosuppressive Agents; Integrin alpha4beta1; Integrins; Lymphoma, B-Cell; Mice; Mice, SCID; Polyenes; Receptors, Lymphocyte Homing; Sirolimus; Spleen; Tacrolimus; Tumor Cells, Cultured; Vascular Cell Adhesion Molecule-1

In immunocompromised HIV-infected and transplanted patients, there is a risk of developing Epstein-Barr virus (EBV)-associated lymphoproliferative disorders (LPD) and lymphomas. EBV has previously been detected by the polymerase chain reaction (PCR) in cerebrospinal fluid from all AIDS patients with EBV-associated cerebral lymphomas. We therefore thought it would be of interest to determine whether transplant patients with extracerebral EBV-associated LPD have detectable EBV genomes in serum. Nested PCR (nPCR) showed that 58% (18/31) of liver transplant (LTX) patients had EBV DNA in 17% (21/125) of serum samples obtained within the first 3 months after LTX. In 39% (7/18) of the patients, the first EBV nPCR-positive sample was found within 2 weeks post-LTX. Basic immunosuppression with cyclosporin A or FK506 did not seem to influence the frequency of detectable EBV genomes in serum. In contrast, positive EBV nPCR correlated to secondary OKT3 treatment for severe acute rejection (P = 0.009). EBV-associated malignant lymphoma developed in three patients 2-6 months post-LTX. In all of them, EBV DNA was amplifiable within 12-14 days after LTX. The EBV antibody titers were not directly related to detectable EBV DNA in serum. We conclude that monitoring of LTX patients receiving increased immunosuppression by nPCR for EBV DNA in serum may help in the early identification of those at risk of developing EBV-associated LPD.

Topics: Adolescent; Adrenal Cortex Hormones; Adult; Antigens, Viral; Child; Child, Preschool; Cyclosporine; DNA, Viral; Female; Graft Rejection; Herpesviridae Infections; Herpesvirus 4, Human; Humans; Immunosuppressive Agents; Incidence; Infant; Infections; Liver Transplantation; Lymphoma, B-Cell; Male; Middle Aged; Muromonab-CD3; Polymerase Chain Reaction; Postoperative Complications; Postoperative Period; Survival Rate; Tacrolimus; Tumor Virus Infections; Viral Proteins; Viremia; Virus Activation

Rapamycin, a potent immunosuppressive drug that prevents rejection of organ transplants in many animals, caused profound growth inhibition in an immature B cell lymphoma, BKS-2, at very low concentrations (2 ng/ml). Similar growth inhibition was also observed in a series of B cell lymphomas (i.e., L1.2, NFS.1.1, and WEHI-279) as well as in thymoma cells. The cell death induced by rapamycin in BKS-2 lymphoma was found to be via programmed cell death, or apoptosis. In contrast to rapamycin, neither FK506 nor CsA affected the normal growth of these cells. FK506, but not CsA antagonized the effect of rapamycin and rescued the BKS-2 cells from undergoing apoptosis. Further, suboptimal concentrations of anti-IgM antibodies and rapamycin acted synergistically in causing the growth inhibition of BKS-2 cells and this inhibitory effect was also completely reversed by FK506. Thus, rapamycin appeared to inhibit lymphoma growth by binding to FK506 binding protein. These results indicate that rapamycin should be evaluated as an effective immunosuppressive therapeutic agent to prevent the incidence of lymphoma after transplantations.

Topics: Animals; Antibiotics, Antineoplastic; Antibodies, Anti-Idiotypic; Apoptosis; B-Lymphocytes; Cell Division; Drug Screening Assays, Antitumor; Immunosuppressive Agents; Lymphoma, B-Cell; Mice; Mice, Inbred CBA; Polyenes; Sirolimus; Tacrolimus; Thymoma; Thymus Neoplasms; Tumor Cells, Cultured

Cytokine-induced killer (CIK) cells are non-major histocompatibility complex-restricted cytotoxic cells generated by incubation of peripheral blood lymphocytes with anti-CD3 monoclonal antibody (MoAb), interleukin-2 (IL-2), IL-1, and interferon-gamma. Cells with the greatest effector function in CIK cultures coexpress CD3 and CD56 surface molecules. CIK cell cytotoxicity can be blocked by MoAbs directed against the cell surface protein leukocyte function associated antigen-1 but not by anti-CD3 MoAbs. CIK cells undergo release of cytoplasmic cytotoxic granule contents to the extracellular space upon stimulation with anti-CD3 MoAbs or susceptible target cells. Maximal granule release was observed from the CD3+ CD56+ subset of effector cells. The cytoplasmic granule contents are lytic to target cells. Treatment of the effector cells with a cell-permeable analog of cyclic adenosine monophosphate (cAMP) inhibited anti-CD3 MoAb and target cell-induced degranulation and cytotoxicity of CIK cells. The immunosuppressive drugs cyclosporin (CsA) and FK506 inhibited anti-CD3-mediated degranulation, but did not affect cytotoxicity of CIK cells against tumor target cells. In addition, degranulation induced by target cells was unaffected by CsA and FK506. Our results indicate that two mechanisms of cytoplasmic granule release are operative in the CD3+ CD56+ killer cells; however, cytotoxicity proceeds through a cAMP-sensitive, CsA- and FK506-insensitive pathway triggered by yet-to-be-identified target cell surface molecules.

Topics: Biomarkers; Bucladesine; CD3 Complex; CD56 Antigen; Cell Line, Transformed; Cyclic AMP; Cyclosporine; Cytokines; Cytoplasmic Granules; Cytotoxicity, Immunologic; Exocytosis; Granzymes; Humans; Killer Cells, Natural; Lymphocyte Activation; Lymphocyte Subsets; Lymphoma, B-Cell; Muromonab-CD3; Neoplasm Proteins; Serine Endopeptidases; Signal Transduction; Tacrolimus; Tumor Cells, Cultured

The WEHI-231 B lymphoma cell line expresses the phenotype of immature B cells. Cross-linking of surface IgM induces programmed cell death (PCD) with typical features of apoptosis demonstrated by the decrease of cell DNA content, chromatin condensation, and nuclear fragmentation. Activation of protein kinase C (PKC) by phorbol esters was reported to protect WEHI-231 cells against apoptosis induced by ligation of antigen receptors. It was therefore hypothesized that PCD could result from a defect in PKC response with an imbalance in the phosphoinositide pathway in favor of Ca2+ mobilization. In support of this hypothesis, we show here that apoptosis can be readily triggered by the calcium ionophore ionomycin. Furthermore, pretreatment of cells with cyclosporin A or FK506 which inhibit selectively the phosphoprotein calcineurin, a calcium-and calmodulin-dependent serine/threonine phosphatase, protects WEHI-231 cells against apoptosis induced by ionomycin or ligation of surface IgM. Unlike phorbol esters, cyclosporin A did not impair the rise of intracellular Ca2+ induced by cross-linking of antigen receptors. Altogether, the data indicate that the phosphorylation status of yet undefined key cellular substrates controls the cellular response to calcium-dependent apoptotic signals in this B cell lymphoma.

Topics: Animals; Apoptosis; Calcium; Cross-Linking Reagents; Cyclosporine; Immunoglobulin M; Immunosuppressive Agents; Ionomycin; Lymphoma, B-Cell; Mice; Polyenes; Receptors, Antigen, B-Cell; Signal Transduction; Sirolimus; Tacrolimus; Tetradecanoylphorbol Acetate; Tumor Cells, Cultured

A new lymphoma cell line, designated SUBL, was established from a Japanese patient with Epstein-Barr virus (EBV)-associated lymphoma, which developed during FK 506 therapy after liver transplantation. This cell line has undergone 80 passages over a period of 22 months. The cultured cells were positive for CD19, CD20, CD21, CD22, CD23, and HLA-DR, and negative for CD10 and surface immunoglobulins. Immunoglobulin gene analysis revealed rearrangements of JH and JK. T-cell antigens or T-cell receptor gene rearrangements were not observed on the cell line. The SUBL cells were positive for Epstein-Barr virus nuclear antigen (EBNA). The EBV genome was detected in the original tissue and the cell line by the in situ hybridization method. These data indicate that this cell line represents the B-cell lineage at a pre-B-cell stage. SUBL cells showed successful heterotransplantation to mice with severe combined immunodeficiency (SCID). Chromosomal analysis revealed the karyotype 46,XY,t(2;3)(p11;q27). Molecular studies showed that c-myc, N-myc, and bcl-2 were not rearranged. This cell line will provide a useful in vitro system to study the relationship between chromosomal abnormalities and the activation of cellular oncogenes.

Topics: Animals; Antigens, CD; Antigens, Viral, Tumor; Burkitt Lymphoma; Cell Transformation, Viral; Child; Chromosomes, Human, Pair 2; Chromosomes, Human, Pair 3; Gene Rearrangement; Herpesvirus 4, Human; Humans; Immunophenotyping; In Situ Hybridization; Liver Transplantation; Lymphoma, B-Cell; Male; Mice; Mice, SCID; Neoplasm Transplantation; Pleural Effusion; Sigmoid Neoplasms; Tacrolimus; Translocation, Genetic; Tumor Cells, Cultured

Recently, we have described that anti-IgM antibodies profoundly inhibited the growth of BKS-2, an immature B cell lymphoma. In this report, we demonstrated that ionomycin alone at very low concentrations (20 nM) inhibited the growth of BKS-2 cells completely. The levels of intracellular Ca2+ induced by the inhibitory concentrations of ionomycin were comparable to those in anti-IgM-treated cells. The growth inhibition caused by ionomycin was reversed by phorbol 12-myristate 13-acetate and lipopolysaccharide. In addition, the immunosuppressants, cyclosporin A and FK506 conferred significant protection from the negative signal induced by ionomycin. However, either cyclosporin A, FK506 or lipopolysaccharide was not found to have direct effect on ionomycin-induced Ca2+ mobilization in BKS-2 cells. Also, ionomycin augmented the anti-IgM-induced growth arrest in these cells. Furthermore, BKS-2 cells that were exposed to anti-IgM or ionomycin underwent apoptosis as characterized by DNA fragmentation. Thus, the characteristics of growth inhibition induced by ionomycin and anti-IgM appeared to be similar in that phorbol 12-myristate 13-acetate, lipopolysaccharide, cyclosporin A and FK506 caused significant reversal from such negative signals and both ionomycin and anti-IgM induced apoptosis in these cells. Altogether, these results showed that the elevation of intracellular Ca2+ alone was sufficient to inhibit the growth of some B lymphoma cells.

Topics: Animals; Antibodies, Anti-Idiotypic; Calcium; Cell Division; Cyclosporine; Cytosol; Immunoglobulin M; Ionomycin; Lipopolysaccharides; Lymphoma, B-Cell; Mice; Mice, Inbred CBA; Tacrolimus; Tetradecanoylphorbol Acetate