Cutaneous necrotizing granulomatous vasculitis with evolution to T cell lymphoma

The evolution of unusual cutaneous vasculitis to a systemic T cell lymphoma was observed over a 12-year period. Precise classification of the skin biopsy specimens during the course of this patient's illness was difficult. Different observers suggested malignant hemangioendothelioma, malignant lymphoma, regressing atypical histiocytosis, and granulomatous vasculitis. In retrospect, the biopsy specimens likely represented the spectrum of cutaneous lymphomatoid granulomatosis. This condition is yet another example of a reactive lymphoid proliferation proceeding to a malignant lymphoma.     

Human hepatoma-associated cell surface antigen: identification and characterization by means of monoclonal antibodies

A library of murine monoclonal antibodies reactive with human hepatoma cells was generated following immunization of Balb/c mice with an intact cloned human hepatoma cell line, designated PLC/PRF/5-NR. We report the characterization of one such IgG2a antibody, designated anti-PLC1. This antibody specifically stains parental PLC/PRF/5 cell membranes and membranes of SK-Hep 1 and Mahlavu human hepatoma cells grown in culture, using indirect immunofluorescence and horseradish immunoperoxidase techniques. A similar pattern of membranous staining was observed in solid tumors derived from the three hepatoma cell lines which were injected subcutaneously into athymic nude rats and mice. Spontaneous capping on the cell surface was observed in 7 to 30% of the three human hepatocellular carcinoma cell types when incubated in suspension with monoclonal anti-PLC1 at 37 degrees C. Treatment of cells with trypsin or sustained growth in culture did not affect the intensity of membranous staining. Monoclonal anti-PLC1 appeared specific, and antibodies did not stain a variety of human carcinoma cell lines and primary tumors of nonhepatic origin, or several normal human and murine tissues. Purified 125I-labeled monoclonal anti-PLC1 bound specifically to the three hepatoma cell lines in culture. Specificity of the antigen-antibody reaction was demonstrated by competitive binding inhibition in experiments using unlabeled homologous antibody. Binding of 125I-anti-PLC1 was not inhibited by unlabeled monoclonal antibodies to HBsAg or to alpha-fetoprotein. Two hepatoma cell lines secrete a protein that specifically blocks binding of 125I-anti-PLC1 antibodies to cell surface antigenic determinants. This "hepatoma-associated" protein was subsequently purified by affinity chromatography from supernates derived from the three hepatoma cell lines.(ABSTRACT TRUNCATED AT 250 WORDS)     

Cutaneous plaque in adult T cell leukemia/lymphoma: A case report

Rationale:The rarity of adult T cell leukemia/lymphoma (ATLL) in China, coupled with its clinicopathologic mimicry of primary skin disease, poses a diagnostic challenge. The method of diagnosis and mechanism of immune regulation in ATLL are discussed in the present report.Patient concerns:A 51-year-old Chinese man was admitted to the hospital with 2-years history of systemic plaque lesions and 1-year history of left ankle joint pain.Diagnoses:The patient was diagnosed with ATLL based on the results of flow cytometry immunophenotype and human T-cell lymphotropic virus type 1 (HTLV-1) serology.Interventions:The patient received 3 cycles of cyclophosphamide, epirubicin/ vinorelbine, and dexamethasone (CHOP) chemotherapy. However, he relapsed and did not respond to epirubicin, vindesine, etoposide, dexamethasone (EPOCH) chemotherapy.Outcomes:His family discontinued the treatment and opted for hospice care.Lessons:Patch and plaque ATLL types exhibits a better survival rate, but atypical skin patches delays the diagnosis of ATLL and negatively affects the patient survival. Based on the present findings, we suggest that patients with petal-like nuclear lymphocytes in blood smears, a high CD4: CD8 ratio, and strong CD25 expression should undergo HTLV-1 serology testing.     

Retention of B-cell-specific monoclonal antibodies by human lymphoma cells

The rates of endocytosis, intracellular degradation, and cell-surface shedding of 125I-labeled monoclonal antibodies (MoAbs) HD-37 (anti- CD19), B1 (anti-CD20), MB-1 (anti-CD37), BC8 (anti-CD45), and DA4-4 (anti-mu) by B-lymphoma cells were compared by cellular radioimmunoassay, ultrastructural autoradiography, sodium dodecyl sulfate-polyacrylamide gel electrophoresis, and thin layer chromatography using biopsy specimens from 12 patients with non- Hodgkin's lymphomas. 125I-BC8 was stably retained on the surface of lymphoma cells without appreciable internalization or shedding, whereas 125I-DA4-4 underwent rapid endocytosis and degradation. 125I-B1 was not internalized or degraded by tumor cells, but rapidly dissociated from the cell surface in intact form. Moderate rates of endocytosis, intracellular metabolism, and cell-surface shedding were shown by 125I- HD37 and 125I-MB-1. The 3 patients with diffuse, small cleaved-cell lymphomas internalized and degraded antibodies more slowly than did patients with other histologic subtypes. These kinetic differences may be important in the selection of MoAbs for immunotoxin and radioimmunoconjugate therapy of B-cell malignancies.     

Inhibition of specific cell-mediated cytotoxicity by monoclonal antibodies to human T cell antigens

Human T lymphocyte subpopulations recently have been defined by monoclonal antibodies that recognize cell-surface antigens selectively expressed on functionally distinct T cell subsets. The majority (approximately 90%) of the peripheral blood sheep erythrocyte-rosette-forming cells carry the OKT3 antigen. Helper cells are OKT4⁺, whereas cytotoxic/suppressor cells are OKT5⁺ and OKT8⁺. We investigated the effect of several monoclonal antibodies recognizing T cell antigens on certain proliferative responses of T cells and on the effector phase of the specific T cell-mediated cytotoxicity generated in mixed lymphocyte culture (MLC). In the absence of added complement, (i) OKT3 and OKT4 monoclonal antibodies inhibited the proliferative response to phytohemagglutinin (PHA), (ii) OKT3 monoclonal antibody inhibited the proliferative response to allogeneic cells in MLC, and (iii) OKT3 monoclonal antibody significantly and regularly inhibited the effector phase of the specific T cell-mediated cytotoxicity against allogeneic targets (P < 0.001) in a concentration-dependent manner. The OKT5 and OKT8 monoclonal antibodies, again in the absence of complement, inhibited moderately the specific cell-mediated cytotoxicity. This inhibition was observed in some experiments only. Inhibition of the specific cytotoxicity by these antibodies also was observed in secondary responses. In contrast, again in the absence of added complement, none of these antibodies had an effect on the nonspecific cytotoxicity generated in MLC against the K562 targets. The OKT4 antibody in the absence of added complement had no effect on either the specific or nonspecific cytotoxicity. Furthermore, treatment with OKT3 or OKT8 antibody and complement completely abrogated the specific T cell-mediated cytotoxicity but had no effect on the natural killer-like cytotoxicity against the K562 cells. Treatment with the OKT4 antibody and complement had no effect. These results suggest that (i) the T5/T8 and T3 antigens, present on cytotoxic T lymphocytes, may be involved directly or indirectly in the antigen recognition step(s) or the lytic mechanism of T cell-mediated lympholysis; and (ii) nonspecific cytotoxicity against the K562 targets generated in MLC is mediated by cells phenotypically different than those that mediate specific cytotoxicity.     

Cell surface characterization of malignant T cells from lymphoblastic lymphoma using monoclonal antibodies: evidence for phenotypic differences between malignant T cells from patients with acute lymphoblastic leukemia and lymphoblastic lymphoma

A series of monoclonal antibodies was used for the characterization of malignant T cells from 21 patients with lymphoblastic lymphoma (LL). The tumor population from these patients showed a marked degree of phenotypic heterogeneity and a proportion (one-third) of patients had tumor cells that did not conform exactly with the cells normally detected in the thymus. However, these cell populations could be related to the early or common or late thymocyte population (about one- third of the patients in each category). This contrast, with the characterization of malignant T cells from 43 patients with acute lymphoblastic leukemia (ALL) that could be related to either early or common thymocytes, with an exception of two patients categorized as having a tumor population related to late thymocytes. Further phenotypic differences between cells from ALL and LL could be demonstrated by investigation with two additional monoclonal antibodies, A50 and U4. Among patients with malignant T cells related to common thymocyte, 0/12 patients with ALL had cells recognized by A50, where 5/8 patients with LL had A50+ cells. Among patients with early thymocytes, only patients with ALL had cells recognized by U4. In addition, 5 LL patients had cells reactive with J5, a monoclonal antibody recognizing the common ALL antigen (CALLA). Since CALLA was found on cells related to common and late thymocytes, CALLA is neither lineage specific, nor can it be viewed as being peculiar to malignant lymphoid cells arrested at very immature stages of differentiation.     

Biochemical characterization of human melanoma cell surfaces: dissection with monoclonal antibodies.

This report describes the structures of three distinct human melanoma surface antigens detected by monoclonal anti-melanoma antibodies. One antigen, expressed on all melanoma cells and on certain astrocytoma cells but not on any other kind of normal or tumor cell tested, has been shown to consist of our associated polypeptide chains. A second antigen expressed on many but not all melanomas has been identified as the antigenic product of the HLA-D locus, the DR antigen. A third protein antigen is not found on any normal cell tested but occurs on some, but not all, tumors of various origins.     

Cutaneous adverse reactions to therapeutic monoclonal antibodies for cancer

Advances in molecular biology have led to the successful development of targeted monoclonal antibodies to several types of malignancies. By June 2007, nine therapeutic monoclonal antibodies had been approved by the US Food and Drug Administration to treat various human cancers. In general, the adverse reactions of these agents have been milder than their cytotoxic chemotherapy counterparts, but side effects do occur. Cutaneous adverse reactions to the first of these agents were rare, and primarily limited to infusion reactions, local inflammation at injection sites, and ill-defined transient eruptions. However, the use of monoclonal antibody therapy against the epidermal growth factor receptor-1 in gastrointestinal and head and neck cancer has been frequently associated with significant skin reactions. As the use of these agents becomes more widespread, the recognition and management of these skin reactions becomes an increasingly important part of patient care.     

Coincidence of B-cell chronic lymphocytic leukemia and cutaneous T-cell lymphoma (mycosis fungoides): immunologic characterization by monoclonal antibodies

Although rare cases of chronic lymphocytic leukemia (CLL) of the T-cell type have been reported, CLL is more commonly found to be a neoplastic lymphoproliferative disease of B-cell origin. In this article, we describe a patient with long-standing CLL that was immunologically shown to be of the B-cell type, who, during the course of his disease, developed cutaneous T-cell lymphoma (CTCL), which was shown to be of the helper/inducer subtype. The neoplastic lymphoid cells in the skin infiltrate differed morphologically and immunologically from those in the peripheral blood. The occurrence of CTCL during this patient's clinical course represents a second neoplasm arising from a different cell line, rather than a tissue manifestation of the patient's CLL. To our knowledge, this is the first report in which the occurrence of CTCL is documented in a patient with immunologically known B-cell CLL. In addition to establishing the presence of B-cell CLL and CTCL of the helper/inducer T-cell type in the same patient, this case report demonstrates the usefulness and necessity of evaluating lymphoproliferative disorders by means of a multidisciplinary approach.     

Treatment of two patients with B cell lymphoma with monoclonal anti- idiotype antibodies

Mouse monoclonal anti-idiotype antibodies have been used to treat two patients with progressive advanced B cell non-Hodgkin's lymphoma. Transient falls in the level of circulating malignant cells and idiotypic immunoglobulin were produced, and free unbound monoclonal antibody was identified in the serum. Homing of the antibodies to tumor cells in the blood, bone marrow, ascites, and lymph nodes was demonstrated in both patients. Although large amounts of anti-idiotype antibody were given (3.8 g and 5.8 g), no toxic effects were seen, and no antibodies to the foreign mouse protein were made. There was no modulation of the antigen from the tumor cells and no indication of immunoselection. There was evidence of large-scale tumor cell destruction, but only a modest reduction in tumor size. The killing of the tumor cells was mediated by the reticuloendothelial system and not by complement.     

MER2: a red cell polymorphism defined by monoclonal antibodies

Two murine monoclonal antibodies, 1D12 and 2F7, apparently of the same specificity, define a new red cell polymorphism, MER2. 92% of English blood donors are MER2+ giving the gene frequencies MER2+ 0.7159; MER2- 0.2841. Family studies showed that MER2+ is inherited as a Mendelian dominant character and that MER2 is not controlled by any of the main blood group loci. The MER2 antigen is also present on some leukaemia fibroblasts and human cell lines. Using somatic cell hybrids, MER2 appears to be coded for by a gene on chromosome 11 at 11p15.     

Chemotherapy combinations with monoclonal antibodies in non-Hodgkin's lymphoma

Although the use of monoclonal antibodies as single agents has had a tremendous impact on the care of patients with non-Hodgkin's lymphoma (NHL), the greatest benefit has been generated by the addition of monoclonal antibodies to conventional cytotoxic chemotherapy. Rituximab is the monoclonal antibody responsible for all clinical improvement noted to date. The addition of rituximab to cyclophosphamide, doxorubicin, vincristine, and prednisone (CHOP) chemotherapy (R-CHOP regimen) improves the response rate, progression-free survival (PFS), and overall survival (OS) in diffuse large B-cell lymphoma (DLBCL). Adding rituximab to CHOP chemotherapy improves response rates and PFS in mantle cell lymphoma (MCL). Finally, the addition of rituximab to a variety of chemotherapy regimens improves the response rates, PFS, and OS in follicular lymphoma (FL). Several other (epratuzumab, bevacizumab, alemtuzumab) monoclonal antibody-chemotherapy combinations are currently under study in NHL. This review will summarize the data supporting the addition of rituximab to chemotherapy in NHL and discuss preliminary data regarding the use of other monoclonal antibodies in combination with chemotherapy.     

Schistosoma mansoni: characterization of two protective monoclonal antibodies

Two monoclonal antibodies against the surface of S. mansoni schistosomula were found to confer significant passive protection to mice (M7B3A, range 28-70%; M22H12C, range 14-58%). No additive effect was observed when both were transferred together. Neither McAb bound to the cercarial surface but both bound to the surface of in vitro derived schistosomula and schistosomula recovered from mouse skin up to 3 days after infection. The McAbs were species specific, but not S. mansoni strain specific. M22H12C immunoprecipitated an 125I-labelled surface antigen of relative molecular weight (mol. wt) 32 000. In Western blotting of an NP40 schistosomular extract, M7B3A recognized an antigen smear of 13 000-18 000 with a dominant band at 16 000. This 16 000 antigen was recognized by serum from demonstrably immune mice and rats vaccinated with highly irradiated carcariae but not by sera from mice with chronic single sex or bisexual infections.     

Isolation of human monoclonal antibodies by mammalian cell display

Due to their low immunogenicity in patients, humanized or fully human mAbs are becoming increasingly important for the treatment of a growing number of diseases, including cancer, infections, and immune disorders. Here, we describe a technology allowing for the rapid isolation of fully human mAbs. In contrast to previously described methods, B cells specific for an antigen of interest are directly isolated from peripheral blood mononuclear cells (PBMC) of human donors. Recombinant, antigen-specific single-chain Fv (scFv) libraries are generated from this pool of B cells and screened by mammalian cell surface display by using a Sindbis virus expression system. This method allows isolating antigen-specific antibodies by a single round of FACS. The variable regions (VRs) of the heavy chains (HCs) and light chains (LCs) are isolated from positive clones and recombinant fully human antibodies produced as whole IgG or Fab fragments. In this manner, several hypermutated high-affinity antibodies binding the Qβ virus like particle (VLP), a model viral antigen, as well as antibodies specific for nicotine were isolated. All antibodies showed high expression levels in cell culture. The human nicotine-specific mAbs were validated preclinically in a mouse model. Thus, the technology presented here allows for rapid isolation of high-affinity, fully human antibodies with therapeutic potential from human volunteers.     

Bone marrow purging procedure in Burkitt lymphoma with monoclonal antibodies and complement: quantification by a liquid cell culture monitoring system

Using B1, Y29/55 and AL2 monoclonal antibodies (MoAbs) to target Burkitt lymphoma (BL) cell lines, we defined optimal conditions to lyse, in the presence of baby rabbit complement, BL cells in excess bone marrow (BM). After the purging procedure, down to one residual BL cell in 10(6) normal ones was detectable with a liquid cell culture assay. Using a cocktail of three MoAbs, on five different cell lines were observed more than 4 log BL cell depletion in samples contaminated with 1% BL cells and only one failure of the procedure on 17 experiments. However, a sixth line was constantly resistant to the procedure.     

Novel and engineered anti-B-cell monoclonal antibodies for non-Hodgkin's lymphoma

Over the past decade, the safety and efficacy of the anti-CD20 antibody rituximab has resulted in its use in virtually all patients with B-cell non-Hodgkin's lymphoma (NHL). Unfortunately, many patients who initially benefit from rituximab develop resistance while others may never respond. Both the successes and limitations of rituximab have heralded an explosion in research and development of novel monoclonal antibodies. Strategies employed to improve upon rituximab have included developing antibodies to target new epitopes of CD20 and new antigens, humanizing or creating fully human antibodies, and engineering antibodies with a potentially greater capacity for interaction with the host immune system. Each of these strategies has shown varying degrees of preclinical and clinical success. In this review we discuss the rationale for various strategies and report results from clinical trials employing these agents.     

Intrahepatic distribution of T cell and T cell subsets in cases with type B chronic liver disease by peroxidase-labeled antibody method using monoclonal antibodies

Intrahepatic distribution of T cell and T cell subsets was studied in 23 cases with type B chronic liver disease (of which 19 cases were also positive for hepatitis B e antigen) and in 6 cases with non-B chronic liver disease by indirect peroxidase-labeled antibody method using monospecific anti-T antibodies and other reagents (anti-Leu series). Hepatitis B surface antigen (HBsAg) and hepatitis B core antigen (HBcAg) in liver tissue were also observed by the peroxidase-labeled antibody method. Membranous expression of HBsAg was found in 16 out of 23 patients with sero-HBsAg, and HBcAg was detected in 15 of them. In these patients, pan-T cells (Leu-1 positive cells) were the predominant cells in the portal tract and the parenchyma. Particularly, T cytotoxic/suppressor cells (Leu-2a positive cells) were often recognized both in sites of piecemeal necrosis and focal necrosis. In some patients whose liver biopsy specimens were obtained during acute exacerbation of chronic hepatitis, T cytotoxic/suppressor cells as well as pan-T cells were increased remarkably in sites of piecemeal necrosis and focal necrosis. These results suggest that T cell cytotoxicity may play an important role in the pathogenesis of liver cell necrosis in type B chronic liver disease.