Gammapatías biclonales: estudio retrospectivo de 47 pacientes / Biclonal gammopathies: retrospective study of 47 patients

Objetivo. Las gammapatías biclonales se caracterizan por una proliferación clonal de cálulas plasmáticas, o sus progenitores linfoides B, con producción de dos inmunoglobulinas anormales (proteínas M o paraproteínas). No conocemos estudios que hayan analizado esta patología en España. Hemos estudiado las enfermedades subyacentes, características de las paraproteínas y evolución de una serie de pacientes con gammapatía biclonal. Material y métodos. Se revisaron las gammapatías clonales del Servicio de Inmunología del Hospital Puerta de Hierro de Madrid, entre los años 1970 y 2011, seleccionando aquellos pacientes con gammapatía biclonal en una determinación. Se recogieron datos epidemiológicos, enfermedad de base, patologías asociadas, terapias recibidas, paraproteína y cuantificación de inmunoglobulinas. Resultados. De los 1.626 casos de gammapatías clonales, 47 eran gammapatía biclonal (2,89%). La mediana de seguimiento fue de 2 años. La principal entidad asociada fue la gammapatía biclonal de significado indeterminado. La composición de paraproteínas más frecuente fue IgG-IgG. En el 81% de los pacientes con una segunda determinación de paraproteína, había desaparecido al menos un componente M. Un tercio de los pacientes no había recibido tratamiento. Conclusiones. Las gammapatías biclonales se asocian fundamentalmente a gammapatía biclonal de significado indeterminado. Ninguna gammapatía biclonal de significado indeterminado evolucionó a patología maligna. En un elevado porcentaje desapareció al menos uno de los dos componentes clonales, a veces de forma espontánea (AU)

Objectives. Biclonal gammopathies are characterized by the clonal proliferation of plasma cells or their B-lymphoid progenitors and are associated with the production of abnormal immunoglobulins (M proteins or paraproteins). There are no known studies that have analyzed this disease in Spain. We studied the underlying diseases, characteristics of paraproteins and the evolution of a series of patients with biclonal gammopathy. Material and methods. We reviewed clonal gammopathies at the Department of Immunology of Hospital Puerta de Hierro in Madrid, between 1970 and 2011, selecting those patients with biclonal gammopathy in one reading. We collected data on the patient's epidemiology, underlying disease, associated diseases, therapies and paraprotein and immunoglobulin levels. Results. Of the 1626 cases of clonal gammapathies, 47 were biclonal gammopathy (2.89%). The median follow-up was 2 years. The main associated condition was biclonal gammopathies of undetermined significance (BGUS). The most common paraprotein combination was IgG-IgG. Upon conducting a second paraprotein reading, 81% of the patients had lost at least 1 monoclonal component. A third of the patients had not undergone treatment. Conclusions. Biclonal gammopathy are fundamentally associated with biclonal gammopathies of undetermined significance. No biclonal gammopathies of undetermined significance evolved to a malignant disease. In a high percentage of patients, at least 1 of the 2 clonal components disappeared, sometimes spontaneously (AU)

Biclonal gammopathies: Retrospective study of 47 patients. / Gammapatías biclonales: estudio retrospectivo de 47 pacientes.

OBJECTIVES: Biclonal gammopathies are characterized by the clonal proliferation of plasma cells or their B-lymphoid progenitors and are associated with the production of abnormal immunoglobulins (M proteins or paraproteins). There are no known studies that have analyzed this disease in Spain. We studied the underlying diseases, characteristics of paraproteins and the evolution of a series of patients with biclonal gammopathy. MATERIAL AND METHODS: We reviewed clonal gammopathies at the Department of Immunology of Hospital Puerta de Hierro in Madrid, between 1970 and 2011, selecting those patients with biclonal gammopathy in one reading. We collected data on the patient's epidemiology, underlying disease, associated diseases, therapies and paraprotein and immunoglobulin levels. RESULTS: Of the 1626 cases of clonal gammapathies, 47 were biclonal gammopathy (2.89%). The median follow-up was 2 years. The main associated condition was biclonal gammopathies of undetermined significance (BGUS). The most common paraprotein combination was IgG-IgG. Upon conducting a second paraprotein reading, 81% of the patients had lost at least 1 monoclonal component. A third of the patients had not undergone treatment. CONCLUSIONS: Biclonal gammopathy are fundamentally associated with biclonal gammopathies of undetermined significance. No biclonal gammopathies of undetermined significance evolved to a malignant disease. In a high percentage of patients, at least 1 of the 2 clonal components disappeared, sometimes spontaneously.

Production of antigen-specific human monoclonal antibodies: comparison of mice carrying IgH/kappa or IgH/kappa/lambda transloci.

Here we compare human monoclonal antibody (MAb) production from mouse strains that carry disruptions of their endogenous mouse IgH/IgK loci and harbor human IgM + Igkappa(BABkappa) or human IgM + Igkappa + IgA transloci (BABkappa,lambda). We found that whereas both strains proved effective for the isolation of antigen-specific IgM antibodies, many of the IgM MAbs elicited from BABkappa comprise human mu chains that are associated with mouse lambda chains. In contrast, BABkappa,lambda mice gave rise to fully functional, polymeric human IgM antibodies comprising both human IgH and human IgL chains. Therefore, the inclusion of a human Iglambda translocus (in addition to the human IgH + Igkappa transloci) not only diminishes problems of endogenous mouse Iglambda expression but also provides a strain of mice that yields fully human MAbs to a wide range of antigens, as witnessed by the isolation of MAbs to human blood cells, tumor cell lines, and an immunoglobulin idiotype.

Severe cutaneous vasculitis following intravenous infusion of gammaglobulin in a patient with type II mixed cryoglobulinemia.

Intravenous infusion of gammaglobulins (IVIG) is one of the treatments of choice in patients with type II mixed cryoglobulinemia (MC). We describe the case of a patient with MC who suffered an adverse generalised reaction with severe cutaneous vasculitis accompanied by a sudden increase in cryocrit levels shortly after being treated with IVIG. When the same gammaglobulin preparation was added in vitro to a sample of the patient's serum, a strong increment in cryoglobulin precipitation and depletion of the monoclonal IgM peak resulted. We suggest that this simple method of studying the displacement of the precipitation reaction could help to predict the outcome of treatment and must be performed before starting IVIG in patients with MC.

Active idiotypic vaccination in a patient with biclonal follicular lymphoma.

Specific immunological responses to the idiotypic epitopes present in the surface immunoglobulin (Ig) of the clonal tumour population can be induced for active immunotherapy in patients with B-cell non-Hodgkin lymphoma (NHL). The clonality of the tumour cells should have important implications for the success of the implemented therapy. Here we report on the case of a patient enrolled in a protocol of active idiotypic immunotherapy in which previous cytofluorometric analysis showed a major IgM+, kappap+ population in the tumoral cell suspensions. However, sequence analysis of both tumour sample and tumour-derived hybrids revealed the presence of two unrelated clones that used different VH and VK gene segments. It was possible to obtain hybridomas secreting these two different IgM, kappap idiotypic proteins. The patient was immunised with a mixture of these two idiotypic Igs conjugated to keyhole limpet haemocyanin. Anti-idiotypic antibodies directed against both tumour-associated proteins were detected. This is the first case of anti-idiotypic therapy in a patient with a biclonal NHL. Our work calls attention to the question of clonality in the context of idiotypic vaccination in NHL patients.

Infusion of lymphocytes obtained from a donor immunised with the paraprotein idiotype as a treatment in a relapsed myeloma.

A 48-year-old patient with IgA k multiple myeloma received a BMT from his HLA-matched sibling. After transplantation, the disease relapsed. Melphalan therapy followed by reinfusion of haemopoietic blood stem cells collected from the patient led to the improvement of the clinical status, although mixed chimerism and an elevated serum IgA persisted. Successful donor immunisation against an immunogenic preparation of the recipient monoclonal protein was performed before the infusion of donor T lymphocytes (DLI) into the patient. Ten weeks after the lymphocyte infusions, no monoclonal band was evidenced and donor complete chimerism was detected. The patient did not develop GVHD. Once complete remission was achieved, the idiotype vaccine was administered to the patient. Nineteen months after DLI, the patient remains in remission. Bone Marrow Transplantation (2000).

Autoantibody activity of the immunoglobulin secreted by a follicular B-cell lymphoma.

In patients with B-cell lymphoma, only in rare cases a secreted paraprotein is found, and in very few of them an associated autoantibody activity has been demonstrated. Here we report the case of a patient with a low-grade B-cell lymphoma with a serum biclonal paraprotein (G,M)lambda and severe erythroblastopenia. Indirect immunofluorescence studies of total serum revealed cytoplasmic (Hep-2 cells) and extracellular matrix (rat tissue sections) staining, suggestive of a new specificity. After gel filtration of serum samples, only the IgM-containing fraction showed the same pattern of staining. Tumor-derived hybridomas expressed an unmutated V3-11 gene identical to that found in tumor samples and secreted an IgM immunoglobulin endowed with the same reactivity, which confirms the tumoral origin of the tissue-reactive protein. The results suggest a link between the autoimmune condition in this patient and the novel specificity displayed by the tumor-derived immunoglobulin.

An association between viral genes and human oncogenic alterations: the adenovirus E1A induces the Ewing tumor fusion transcript EWS-FLI1.

Malignant transformation of human cells requires the accumulation of multiple genetic alterations, such as the activation of oncogenes and loss of function of tumor suppressor genes or those related to genomic instability. Among the genetic alterations most frequently found in human tumors are chromosomal translocations that may result in the expression of chimeric products with transforming capability or are able to change the expression of oncogenes. We show here that the adenovirus early region 1A (E1A) gene can induce a specific human fusion transcript (EWS-FLI1) that is characteristic of Ewing tumors. This fusion transcript was detected by RT-PCR in normal human fibroblasts and keratinocytes after expression of the adenovirus E1A gene, as well as in human cell lines immortalized by adenoviruses. Cloning and sequencing of the RT-PCR product showed fusion points between EWS and FLI1 cDNA identical to those detected in Ewing tumors. In addition, we detected a chimeric protein by western blot analysis and immunoprecipitation and a t(11,22) by fluorescent in situ hybridization. This association between a single viral gene and a specific human fusion transcript indicates a direct link between viral genes and chromosome translocations, one of the hallmarks of many human tumors.

Isolation of tumor-derived immunoglobulin-idiotype from peripheral blood mononuclear cells in a B-cell lymphoma patient with minimal disease.

Active immunization with autologous idiotypic immunoglobulin, obtained by somatic fusion techniques, has been shown to be a useful alternative treatment in patients with B-cell lymphoma. Nevertheless, the requirement for biopsy specimens to obtain lymphoma cells could be a limitation to this therapeutic strategy. We address the question of whether peripheral blood samples containing small amounts of tumor cells can be used as appropriate fusion partners to rescue tumor-derived idiotypic proteins. In this report, we show that hybrid cells can be obtained from somatic fusions of K6H6/B5 heterohybridoma with lymphoma cells obtained from both lymph node (LN) and peripheral blood mononuclear cells (PBMC) containing only minor amounts of tumor cells. Some hybrid cells obtained from LN or PBMC fusions present an immunoglobulin (Ig) heavy-chain gene rearrangement identical with that of the original tumor and secrete identical Ig protein containing the expected H and L chains.

Delimitation of the proliferative stages in the human thymus indicates that cell expansion occurs before the expression of CD3 (T cell receptor).

Precursor of T lymphocytes undergo proliferation and maturation under the influence of the thymic microenvironment. In our study, we have attempted to determine the distribution of human postnatal thymocytes in division according to their stage of differentiation. Our data show that about 11.5% of all thymic cells are in S/G2/M phases, and that a subset of the cortical and precortical subpopulations contains most of the dividing cells. Rate of cell division is maintained at high levels from the prethymocyte precursor along the successive stages of differentiation represented by CD1+CD3-CD4-CD8- and CD1+CD3-CD4+CD8- cells. The percentage of dividing cells is maximal in an intermediate subset of CD1+CD3-CD4+CD8-CD45RO+ cells defined by the distinct expression of class I HLAdim/high molecules, which could contain cells in transit from prethymocytes to double-positive cortical cells. The CD3- fraction of the double-positive cortical cells contains most of the dividing thymocytes, although the rate of division within this subset is much less than that of the precursor CD1+CD3-CD4+CD8- cells. In a linear scheme of differentiation, cell division stops at or near the point of initiation of CD3 expression. These results suggest that in human thymus cell expansion takes place before the initiation of the positive selection process. According to this view the stringency of the selection process would require the previous generation of a large number of precursors to permit the production of sufficient numbers of mature T cells.

Apoptosis in human thymocytes after treatment with glucocorticoids.

Treatment of unfractionated human thymocytes in culture with the synthetic glucocorticoid dexamethasone induced cell death, as measured by trypan blue exclusion, after several hours of incubation. In purified subsets of human cortical and medullary thymocytes dexamethasone caused cell lysis with similar kinetics in both populations; 50% of thymocytes were killed after 20-24 h of incubation with the steroid. The mechanism of dexamethasone-induced cell death seems to correspond to apoptosis since degradation of DNA into oligonucleosome-sized fragments could be observed in the cultures treated with the steroid. A certain degree of DNA fragmentation and cell death could also be observed in control cultures of thymocytes. In contrast, peripheral T lymphocytes were resistant to the cytolytic effect of glucocorticoid hormone. The killing of human thymocytes by dexamethasone was inhibited by cycloheximide, suggesting that this cell death program requires a fully operating protein synthesis machinery and perhaps the induction of new proteins.

Differential interleukin secretion by in vitro activated human CD45RA and CD45RO CD4+ T cell subsets.

The CD45RA and CD45RO isoforms have been reported to define complementary subsets among CD4+ T cells: CD45RA CD4+ T cells are considered "virgin T cells" and CD45RO "primed T cells." We investigated the secretion of lymphokines by human CD4+ CD45RO and CD4+ CD45RA T helper cells after mitogen stimulation. CD45RA and CD45RO CD4+ T cells were isolated by negative immunoselection using magnetic beads. CD45RO cells, but not CD45RA cells, proliferate well in response to pokeweed mitogen (PWM) or insoluble anti-CD3. Both subpopulations produced interleukin (IL)-2, IL-6, and interferon (IFN)-gamma when stimulated with PWM for 1-4 days. Only Day 1 supernatants from CD45RO cells contained moderate amounts of IL-4. After 14 days of continuous culture and stimulation with PWM, the CD45RA subset had lost the expression of CD45RA and gained that of CD45RO. When long-term cultured CD45RA or CD45RO cells were treated with insoluble anti-CD3, they incorporated [3H]thymidine at similar levels, but only CD45RO cells secreted IL-4 and significantly increased their secretion of IFN-gamma. These data indicate that despite phenotype conversion, the two subpopulations maintain functional differences in the secretion of lymphokines, thus suggesting that circulating CD45RA and CD45RO cells may represent different lines of differentiation.

Proliferative responses induced by the activation of protein kinase C during the development of human T lymphocytes.

We have studied the effects of phorbol-dibutyrate (PBu2), a protein kinase C (PKC) activator, on the proliferation of peripheral human T cells and thymocyte subpopulations selected by treatment with monoclonal antibodies and complement: pre-thymocytes (CD1a-CD3-CD4-CD8-), cortical thymocytes (CD3-, class I- antigens) and medullary thymocytes (enriched as CD1a- cells). PBu2 induces a dose-dependent proliferative response in human peripheral blood T cells at concentrations greater than 6 ng/ml, this proliferation being mediated by the autocrine interleukin 2 (IL2)/IL2 receptor (IL2R) pathway. Pre-thymocytes respond to PBu2 in a way similar to T cells, being able to secrete IL2 in significant amounts and express the p55 chain of IL2R. On the other hand, cortical thymocytes are not induced to proliferate after PKC activation and neither expression of the p55 chain of IL2R nor IL2 secretion is observed. Human medullary thymocytes, phenotypically identical to peripheral blood T cells, show no proliferation in response to PBu2 at any concentration tested unless IL2 is supplied to the cultures. The activation of PKC induces the expression of IL2R in these cells, but not IL2 secretion. The implications of PKC activation in thymic maturation, the role of IL2 and the relevance of the differences between medullary thymocytes and peripheral blood T cells are discussed.

IL-2 protects against anti-CD3-induced cell death in human medullary thymocytes.

In recent years, several studies have confirmed the clonal elimination of thymocytes with receptors that recognize Ag and MHC molecules present on the membrane of thymic stromal cells, a process that may be relevant to the establishment of self-tolerance. In our work, we show that anti-CD3 treatment of single positive CD4+ or CD8+ human medullary thymocytes (obtained by anti-CD1a plus C) induces their apoptotic death. Some events commonly associated with the early steps of normal activation (IL-2R expression, increase in cytoplasmic Ca2+) are also induced after anti-CD3 treatment. Nevertheless, IL-2 is not secreted by these activated cells. The addition of exogenous IL-2 inhibits the apoptosis induced by anti-CD3. We suggest that the lack of secretion of IL-2 by medullary thymocytes may be a physiologic mechanism implicated in the process of negative selection that leads to tolerance.

Correlated expression of surface antigens in human thymocytes. Evidence of class I HLA modulation in thymic maturation.

The correlated expression of several surface antigens (CD 1, class I HLA, CD3) was examined in human unfractionated thymocytes or selected subsets by using single or double-color flow cytometry. Prethymocyte subpopulations expressed high levels of HLA. A high proportion of cortical cells expressed low levels of either HLA or CD 3 antigens. Most of these HLA+ cortical cells corresponded to the more immature cells and did not express HLA-B loci products. CD 1 a and CD 3 antigens were expressed in a high percentage of cells and the levels of expression of each antigen in individual cells were inversely correlated. These data and the contour of double-color histograms are suggestive of the existence of a single pathway of thymocyte differentiation in which class I HLA expression is switched off around the time of the initiation of CD 3 (and Ti?) expression. We suggest that the anti-major histocompatibility complex (MHC) specificity of the unselected Ti receptor may be incompatible with the expression of MHC products on the cell membrane. At this stage, CD 1 antigens, whose expression is inversely correlated with that of HLA, may fulfill the role of MHC antigens. The latter can be re-expressed later on, once the anti-MHC specificities of the Ti receptors have been selected against. Studies on in vitro modulation of HLA molecules by interferon-alpha did not reveal any correlation to the expression of CD 1 or CD 3 antigens.

The regulation of membrane-bound and secreted immunoglobulins in the human lymphoid cell line LICR-LON and human hybridomas.

The synthesis of membrane-bound and secreted immunoglobulin was investigated in the human line LICR-LON-HMy2, a cell line often used for the derivation of human hybridomas. PAGE-SDS analysis of immunoprecipitates obtained from 35S-methionine labelled cell lysates shows that LICR-LON synthesize a hitherto undetected membrane form of IgG (with a heavy chain of mol. wt 62,000) in addition to the secretor form of IgG already described (55,000 heavy chain). Tunicamycin treatment, pulse-chase experiments and Western blot analysis showed that both chains are synthesized as independent proteins. Hybridomas obtained after fusion of LICR-LON and human peripheral blood lymphocytes retained the ability of the parental cell line to synthesize gamma m and gamma s. Some of these hybrids synthesize and secrete IgM which presumably originates from the parental B-lymphocytes. Precipitation and PAGE-SDS analysis of membrane proteins after iodination of intact cells revealed only one heavy chain band, corresponding in size to that of the gamma m. No indication of the synthesis of the membrane form of IgM was found in the hybrids. These data show that the parental (lymphoid) phenotype (m and s-IgG) is codominant with the more differentiated phenotype (s-IgM) of the fusion partner cell (plasma cell). These observations are compatible with a class-specific m-s regulation operating on a different chromatin structure at the expressed Ig loci of each parental chromosome.

Effect of purified human interferon-alpha on the expression of differentiation antigens and mitogen reactivity of cultured human thymic cells.

Human thymic cells were cultured in vitro either alone or with the addition of a highly purified preparation of human interferon-alpha. Immunofluorescence techniques using a series of monoclonal antibodies showed that 2-day cultured thymocytes express a more mature phenotype (low HTA 1, high T3 and HLA-A,B,C) than normal, uncultured thymocytes. Interferon addition to the cultures results in a strong increment in the number of HLA+ cells and in the total amount of HLA expressed by the cultured cells. Experiments with purified cell populations showed that the cortical, immature, thymocyte was the target cell for interferon action. Phytohemagglutinin responses--but not interleukin 2 responses--were diminished after pretreatment of thymic cells with interferon. We suggest that interferon may favor a pathway of intrathymic differentiation phenotypically characterized by a high content of Class I HLA antigens.

Mitogen-induced changes in glycolytic enzymes of mouse lymphocytes: influence of insulin on cell activation in vitro.

Activated mouse spleen lymphocytes have increased amounts of the glycolytic enzymes pyruvate kinase and lactate dehydrogenase. No changes were found in hexokinase and in the gluconeogenic enzyme fructose 1,6-diphosphatase. Concanavalin A-activated T cells give higher activities of those enzymes than lipopolysaccharide-activated B lymphoblasts. Insulin treatment results in a stronger increment of the enzyme activity of mitogen-activated cells. Insulin inhibits the initial proliferation induced by either Con A or LPS, but a 50% increase in antibody-forming cells was found in LPS-treated cultures. Insulin may favour the differentiation of activated cells by increasing the rate of the glycolytic pathway.

Alkaline phosphatase activity as a membrane marker for activated B cells.

Alkaline phosphatase activity was assayed by a microtiter assay (with p-nitrophenylphosphate used as substrate) in the plasma membrane of mouse spleen cells activated in vitro by the B cell mitogen LPS and the T cell-dependent B cell mitogen, PWM. No activity was detected in spleen cells cultured in the presence of the T cell mitogens PHA and Con A. This alkaline phosphatase activity was detected in the blast-enriched 30 to 40% fraction of discontinuous Percoll gradients in LPS-treated cultures, and the enzymatic activity assayed was susceptible to inhibition by the alkaline phosphatase inhibitors EDTA and L-phenylalanine. These data support the idea that the membrane alkaline phosphatase activity could be used as a marker for activated B cells.