Impaired synthesis of polyclonal (non-paraprotein) immunoglobulins by circulating lymphocytes from patients with multiple myeloma Role of suppressor cells

CD5 positive immunoregulatory B cells in spleen populations from multiple myeloma patients

CD19+CD5+ lymphocytes constitute a minority of peripheral blood B cells. In view of the importance of these cells in the pathogenesis of the immunoregulation of myeloma, their incidence in another lymphoid organ was determined. CD5+ B cells were studied in 9 spleens from patients with multiple myeloma and in 10 spleens from normal individuals removed secondary to trauma. The total number of CD19+ B cells were increased in myeloma spleens (44.4% +/- 12.6%) as compared to normal spleens (20.4% +/- 7.4%). Likewise, the percentage of CD19 cells which co-expressed CD5 were increased in myeloma (25.3% +/- 12.4%) versus normal (4.4% +/- 2.3%) spleen. CD5+ B cells isolated from myeloma spleens, but not normal spleens, inhibit production of immunoglobulin in a pokeweed mitogen driven assay. Thus the spleen appears to be an important source of immunoregulatory B cells in multiple myeloma.

Immunoregulatory cell dysfunction in chronic B-cell leukemias

Chronic B-cell malignancies are routinely characterized as B-cell clonal diseases that have signs and symptoms primarily related to the continuing expansion of these cells. This review discusses chronic lymphocytic leukemia, multiple myeloma and hairy cell leukemia from the perspective of secondary abnormalities in non-malignant cells. Thus, our main purpose is to elaborate on the alterations/abnormalities of the immunoregulatory (IR) cells in these diseases and focus on the qualitative and quantitative aspects of T-cells, natural killer (NK) cells and monocytes. The relevance of the IR-cell changes to the basic disease process and their complications are emphasized.

Cryopreservation enhances interleukin-1 production in human mononuclear cells

The effects of cryopreservation on bacterial lipopolysaccharide (LPS)-induced interleukin-1 (IL-1) production by unfractionated mononuclear cells (MNCs), adherent cells (ACs), and nonadherent cells (NACs) were studied. Culture supernatants from cryopreserved cells contained significantly larger concentrations of IL-1 [MNCs, 211 +/- 50; ACs, 640 +/- 41; NACs, 116 +/- 19 U/ml (mean +/- SEM)] as compared with supernatants from fresh cells (69 +/- 22, 427 +/- 69, and 72 +/- 33 U/ml, respectively). In addition, supernatants obtained from cocultures of autologous fresh and frozen cells contained much less than the expected quantities of IL-1 (78 +/- 8%), indicating that suppressor cells in the fresh population are responsible for the decreased IL-1 content. The studies suggest that functional inactivation of cryosensitive suppressor monocytes is associated with an increase in IL-1 production by the other subset. The results provide further evidence that lack of active suppressor monocytes and increased IL-1 production may be responsible for the previously reported enhanced plaque-forming cell responses of cryopreserved cells from normal controls and from patients with lung cancer.

The effect of ranitidine on cellular immunity in patients with multiple myeloma

Multiple myeloma is characterized by an increased susceptibility to infections and to other malignancies. In a double-blind, placebo-controlled study the potential impact of immunomodulation by ranitidine was studied in 20 patients with multiple myeloma. Three patients were untreated, while 17 after previous cytotoxic therapy were in a stable phase of their disease. All were without clinical signs of infections and at that time had not been treated with other immunomodulating agents. The patients were randomized to oral ranitidine 300 mg twice a day for 21 days or placebo, and several immunological parameters related to multiple myeloma were studied. The blood monocyte chemotactic response was improved in patients treated with ranitidine, and superoxide anion production increased from 2.02 nmol/min to 3.86 nmol/min (median values), while it was unchanged in patients given placebo (2.19-2.25 nmol/min) (P less than 0.005 between groups). Among ranitidine-treated patients spontaneous NK cell activity was unchanged, while in vitro interleukin-2- and interferon-alpha-stimulated NK cell activity decreased (P less than 0.03, respectively). As production of oxygen radicals constitutes an important mechanism of monocyte killing activity against microorganisms and probably against malignant cells, it is suggested that ranitidine may be of beneficial impact in the treatment of multiple myeloma.

Complement abnormalities in multiple myeloma

PURPOSE

Patients with multiple myeloma have been shown to have defective opsonization and C3 deposition. Previous studies have suggested that defective C3 deposition may be related to a failure of C3 activation in myeloma serum, the mechanism of which is unknown. We therefore decided to investigate the underlying mechanism responsible for the failure in C3 activation and deposition.

PATIENTS AND METHODS

The study consisted of 10 patients from whom a total of 12 serum specimens were obtained. Normal serum was prepared from a pool of serum specimens in four healthy male donors. We evaluated, in vitro, the kinetics of C3 deposition onto zymosan using radiolabeled C3 under various conditions. We also measured the serum levels of a variety of complement components using standard methods.

RESULTS

Five of 10 patients' sera demonstrated poor C3 deposition onto zymosan at all time points, whereas an additional two showed poor C3 deposition at early time points but a rebound to normal by 30 minutes. Multiple components of the classical and alternative complement pathways were decreased in many patients, with the most striking abnormalities occurring in those with the poorest C3 deposition. No single complement component abnormality was found to be common to the group. Elevations in Bb fragment concentration strongly suggest in vivo activation as the likely mechanism for depletion of alternative pathway components; the mechanism for classical pathway abnormalities is less clear. There was an inverse correlation between paraprotein concentration and abnormal C3 deposition (p less than 0.0001) and C3 (p less than 0.0005) and C4 (p less than 0.0001) concentrations. However, no consistent evidence of fluid-phase complement consumption was present.

CONCLUSION

The defect in C3 activation and deposition in multiple myeloma cannot be explained on the basis of a single complement component abnormality but rather is due to a heterogeneous group of complement abnormalities. Although no correlation between in vitro abnormalities and clinical status was identified in this small group of patients, it is likely that the described complement defects play an important role in defective host defense in multiple myeloma.

Limiting dilution cloning of B cells from patients with multiple myeloma: emergence of non-malignant B-cell lines

Multiple myeloma (MM) is a B-cell malignancy characterized by the accumulation of slowly proliferating malignant plasma cells in the bone marrow (BM). Several reports have shown the existence of an abnormal B-cell compartment including proliferative idiotypic B cells (i.e., B cells bearing the same idiotypic determinants as the myeloma protein) in the BM and peripheral blood (PB) of patients with MM. In order to study whether this abnormal compartment can be grown in vitro, we cultured the PB and BM of 23 patients with MM using limiting dilution methods. Our purpose was to restrict the effect of suppressor cells and the possible overgrowth of the cultures by the more rapidly growing B cells, which occurs in bulk cultures. Spontaneously growing cells were obtained only from patients seropositive for the Epstein-Barr virus (EBV) and all the cultures were composed of B cells carrying the EBV genome. Thus, positive cultures were generated only in the presence of B cells latently infected with EBV in vivo. The mean frequency of these B cells (1 in 25,000 B cells) was as low in MM patients as in healthy donors. This low frequency indicated that malignant cells do not bear the EBV genome in vivo and that the in vivo regulation of the EBV infection is unaffected in patients with MM. No Ig-gene rearrangements, specific of the autologous myeloma cells, were found in the cell lines obtained from BM or PB. Thus, the putative malignant B cells or myeloma cells were not able to generate cell lines in vitro, either spontaneously or after endogenous infection with EBV.

B lymphocyte function in multiple myeloma: analysis of T cell- and monocyte-dependent antibody production

T-cell and B-cell functions were studied in 35 patients with untreated multiple myeloma (MM) and in 16 patients with MM treated with prednisolone, melphalan and vincristine. The numbers of CD4+ T cells were normal in untreated MM patients, but markedly decreased in treated patients, whereas CD8+ cell numbers were normal in untreated and treated patients. Mitogen-induced as well as antigen-induced lymphocyte proliferative responses were reduced, but not further affected by treatment. The antigen-induced proliferative responses by lymphocytes of treated, but not of untreated patients, correlated positively to the proportions of CD4+ cells among MNC. Taken together, the findings suggest selective loss of CD4+ subpopulations during cytotoxic treatment. Pokeweed mitogen (PWM)-induced Ig production was generally low, but significantly reduced Ig production was only seen in experiments employing MM B cells and monocytes co-cultured with irradiated T-enriched cells. Irradiated MM T cells displayed normal helper function when co-cultured with normal B cells stimulated with PWM. MM B cells and monocytes cultured with irradiated normal T cells produced little Ig; however, MM monocytes were not suppressive. In 2 of 3 patients with either IgG-kappa or IgA-kappa myeloma, the numbers of PWM-stimulated B cells that produced kappa chains were somewhat higher than those found among normal MNC. The impaired ability of antibody production by B cells from untreated MM patients seems to relate to intrinsic B cell defect(s) rather than to abnormal regulation by T cells or monocytes. However, disturbances in the functions of CD4+ cells may be observed in treated MM.

Increase in the suppressor-inducer T cell subset in multiple myeloma and monoclonal gammopathy of undetermined significance

The expression of CD4 (helper-inducer), CD8 (suppressor-cytotoxic) and CD4 subpopulations (2H4 and 4B4) were studied in patients with multiple myeloma, monoclonal gammopathy of undetermined significance (MGUS) and in healthy controls. The percentages of CD4+ cells and CD8+ cells among total T cells were not different between the three groups studied. However the percentage of CD4+ cells of the suppressor-inducer type (CD4 + 2H4 +) was 53 +/- 9% in patients with MGUS, and 51 +/- 9% in those with MM, compared to 46 +/- 5 in the controls (P = 0.033 and P = 0.07 respectively). A significant negative correlation between serum polyclonal IgM and the percentage of CD4 + 2H4 + cells was found in patients with MM but not in those with MGUS. No difference was found in the percentage of CD4 + 4B4 + (helper CD4+ cells) between the various groups. These findings suggest that the elevation of the suppressor-inducer subset occurs prior to clinical manifestations of MM, perhaps as an immune response to the malignant clone. The existence of elevated proportions of CD4 suppressor-inducer cells was associated with the hypogammaglobulinaemia observed in patients with MM. Since no hypogammaglobulinaemia was present in those with MGUS, additional factors are needed to explain the influence of the CD4 + 2H4 + cells on the production of immunoglobulins.

Altered cytokine activities are related to the suppression of synthesis of normal immunoglobulin in multiple myeloma

The content of peripheral blood B cells (B1+) was reduced in patients of multiple myeloma (MM) and not in those with benign monoclonal gammopathy (BMG) compared to normal donors (P less than 0.01). This observation correlated with the suppression of synthesis of normal immunoglobulin (Ig) in MM. Thus, cytokine activities regulating the proliferation of normal mature B cells, such as B cell stimulatory factor 1 (BSF-1)/interleukin 4 (IL-4), B cell growth inhibitory factor (BIF) and IL-2 in peripheral blood T cells, and IL-1 in peripheral blood adherent cells, were investigated in patients with BMG (n = 7) and MM (n = 28). All patients of MM having a marked suppression of synthesis of all other normal Ig, had significantly lower levels of BSF-1 activity and inversely higher levels of BIF activity than those of normal donors. However, patients with BMG having no suppression of synthesis of normal Ig had BSF-1 and BIF activities similar to normal donors. There was no significant difference in IL-1 and IL-2 activities between both normal donors and BMG versus MM patients. These data show that in MM altered cytokine activities correlate with suppression of synthesis of normal Ig.

The defect in peripheral blood B-cell activation in patients with multiple myeloma is not due to a deficiency in the production of B-cell growth and differentiation factors

The suppression of B lymphopoiesis is a major feature of multiple myeloma (MM). In this disease, there is a striking defect in the response of peripheral blood B cells to pokeweed mitogen (PWM). Normally, B-cell activation depends on B-cell growth factors (BCGFs) and B-cell differentiation factors (BCDFs), produced by peripheral blood mononuclear cells. We therefore evaluated whether the production of these cytokines was defective in patients with MM. We have studied the production of BCGFs (using the anti-mu assay) and, particularly, interleukin-2 and interferon-gamma, two well-documented BCGFs. No defect in the production of BCGFs, interleukin-2, and interferon-gamma was found in patients with active (N = 14) or stable (N = 10) MM, compared with healthy donors (N = 13). The production of BCDFs (i.e., overall activity) was also evaluated and, more particularly, that of interleukin-6 (IL-6). This cytokine is a potent BCDF which is essential in the PWM-induced activation of B cells, acting at the terminal stages of B-cell differentiation. Again, no defect in the production of BCDFs and IL-6 was found in patients with MM. Therefore, the ability to secrete cytokines controlling the process of B-cell activation is not affected in such patients. This indicates that the profound failure of humoral immune response is not due to deficiency of peripheral blood mononuclear cells producing these factors.

Phenotypical and functional characterization of the idiotype-positive blood B cells in multiple myeloma

In this study the idiotype-positive B cells of one patient with smouldering multiple myeloma (IgG kappa) and of one patient with multiple myeloma (IgG lambda) were analysed phenotypically and functionally. As regards the expression of B cell-associated differentiation antigens and size distribution, the idiotype-positive B cells resembled normal IgG-bearing blood B cells. In functional studies the lymphocytes were cultured in vitro with Staphylococcus aureus, pokeweed mitogen, T-cell factors, or combinations of these. After culture, proliferation and differentiation of the idiotype-positive B cells were measured by autoradiography, an idiotype-specific ELISA, and a spot ELISA. The results show that idiotype-positive B cells of both patients are able to proliferate after stimulation in vitro. In contrast to their normal counterparts, however, almost no increase in the amount of secreted idiotype IgG could be induced. This suggests that the idiotype-positive blood B cells have lost some of their ability to respond to exogenous stimuli.

T-cells of multiple myeloma patients triggered by the autologous mixed lymphocyte reaction suppress polyclonal immunoglobulin synthesis

To elucidate the possible role of T-cells of patients with multiple myeloma (MM) in the suppression of polyclonal immunoglobulin synthesis. T-cells with and without prior activation by the autologous mixed lymphocyte reaction (AMLR) were added to normal immunoglobulin (Ig)-secreting cultures. The suppression induced by AMLR-activated T-cells from patients with MM was compared to that induced by AMLR-activated T-cells from apparently normal controls. The addition of 10% unstimulated autologous T-cells from patients with MM resulted in minimal suppression of IgG synthesis (87 +/- 19% of baseline values for patients and 115 +/- 21% for controls, no significant difference). The suppression sharply increased when T-cells were preactivated by AMLR and then added in the same concentration to the IgG-secreting cultures (38 + 12% of baseline values for patients compared to 106 + 14% for controls, P less than 0.05). AMLR cultures were performed in the presence of adherent monocytes and after their depletion. The T-cell suppressor effect on normal IgG synthesis was unchanged after monocyte depletion. T-cells preactivated in the AMLR from patients with MM sharply suppress in vitro polyclonal IgG synthesis, and the activation of these suppressor T-cells is not dependent on the presence of monocytes.

Delay and not deficiency in cap formation of peripheral blood B cells in patients with multiple myeloma

A major problem in the study of peripheral blood (PB) B cells from patients with multiple myeloma (MM) is the distinction between the cells really able to synthesize membrane (m) immunoglobulins (Ig) and those able only to absorb serum Ig passively, since the lymphocytes of such patients are bathed in very high concentrations of monoclonal Ig. In order to reappraise PB B cells (including putative pre-B cells) in MM, we have used three different criteria: (a) the capacity of PB B cells to cap mIg when triggered by an anti-Ig; (b) the presence of B-cell differentiation antigens (CD19, CD20, CD21, and CD37) as specific B-cell markers; and (c) the expression of cytoplasmic mu heavy chain as a marker of pre-B cells. We have found that, in active myeloma (N = 13), the percentages and absolute numbers of PB B cells able to cap mIg (4.25%; 45.43 cells/mm3) were significantly lower than those in healthy donors (8.4%; 151.2 cells/mm3) and those in stable MM (7.67%; 134.39 cells/mm3). In addition, the capping formation in patients with stable or active MM was significantly delayed compared to that in healthy donors. For all the normal individuals and patients investigated, there has been found an excellent correlation between the percentages and absolute numbers of PB B cells able to cap their mIg and those of PB mononuclear cells bearing the four B cell-specific differentiation antigens: CD19, CD20, CD21, and CD37. Finally, virtually no pre-B cells bearing cytoplasmic mu chains have been identified in the peripheral blood from healthy donors and patients with MM.

Laboratory investigation of monoclonal gammopathy during 10 years of screening in a general hospital

Protein electrophoresis was carried out on 102,000 samples from the patients of a district general hospital over 10 years, and a monoclonal protein was detected in 730 cases; of these, 114 could be classified as B cell malignancies and 261 as monoclonal gammopathy of undefined significance (MGUS). The various clinical and laboratory features of monoclonal gammopathy were examined with respect to distinguishing the malignant conditions from MGUS at first presentation.

Impaired synthesis of immunoglobulin in patients with chronic lymphocytic leukemia

The cause of hypogammaglobulinemia in patients with chronic lymphocytic leukemia (CLL) is unknown. Experiments were performed to determine if sera, monocytes, or non-T cells from patients with CLL suppress the proliferative response and synthesis of immunoglobulin (Ig) following incubation with pokeweed mitogen (PWM) in cocultures with lymphocytes from normal individuals. The data indicate that sera and monocytes from patients with CLL did not suppress the proliferative response or synthesis of Ig normal non-T cells. When various numbers of normal non-T cells and CLL non-T cells were cocultured with a constant number of normal T cells, the proliferative response and the concentration of supernatant Ig decreased as the proportion of CLL non-T cells increased. Since similar results were obtained when irradiated non-T cells from normal individuals were substituted for non-T cells from patients with CLL, we believe that the decrease in proliferative response and diminished synthesis of Ig is not the result of the suppressor non-T cells but is related to the dilution of normal B cells by inert non-T cells. We conclude that these experiments serve as as in vitro model for patients with CLL and suggest that the hypogammaglobulinemia observed in this disease is related to the diluting out of normal B cells by the accumulation of neoplastic B cells in the peripheral blood, bone marrow, and lymphoid tissue of these patients.

Suppression of in vivo antibody responses by suppressor factors induced by human myeloma proteins

Suppressor factors induced in vitro, using purified human IgG and IgA myeloma proteins, were shown to efficiently suppress murine antibody production in vivo. The suppression was not isotype specific, viz. IgG and IgA suppressor factors suppressed the production of IgM and IgG antibody. Neither the suppressor factors (SF) nor the inducing proteins suppressed the proliferative responses to concanavalin A and purified protein derivative (PPD). The results are compared to the in vitro findings and discussed in the context of isotype regulation, hypogammaglobulinemia and immunotherapy.

Multiple myeloma presenting with primary meningococcal arthritis

A 64-year-old white man presented with Neisseria meningitidis primary septic arthritis. Further evaluation revealed multiple myeloma. Increased susceptibility to infection occurs early in multiple myeloma; thus, a rare cause of primary septic arthritis, such as N. meningitidis, warrants a full evaluation for immunocompromise.

Suppressor T cell activity in lymphoid interstitial pneumonia

A case of lymphoid interstitial pneumonia was investigated for immunological abnormalities. Suppressor T cells were found. The abnormality in the lymphoid system could be corrected in vitro with levamisole. The patient thereafter developed histiocytic lymphoma and soon died without any response to chemotherapy.

HLA-D restriction of "naturally occurring" MLR suppressor cells in acquired common variable hypogammaglobulinemia

Cells with capacity to suppress the mixed lymphocyte response (MLR) were detected in two patients with acquired common variable hypogammaglobulinemia (ACVH). No specificity with respect to the stimulating HLA type was observed. In one case of ACVH available for extensive study, there was evidence for HLA-D restriction of the suppressor cells. The patient's lymphocytes specifically suppressed the MLR of subjects who carried the same HLA-D type. Family studies confirmed that the suppressor activity was restricted to HLA-D, not DR, and segregated with the appropriate HLA haplotype. These observations suggest that an immune suppressor gene mapping in the HLA region may be involved in the pathogenesis of common variable hypogammaglobulinemia.

Impaired immunoglobulin synthesis in multiple myeloma: a B-cell dysfunction

Peripheral blood samples collected from normal individuals and patients with benign monoclonal gammopathy and multiple myeloma were separated and assayed for their T- and B-cell subpopulations as well as immunoglobulin (IgG, IgM) synthesis in vitro. To rule out any functional or quantitative alterations related to therapy, only newly diagnosed multiple myeloma patients and subjects with benign monoclonal gammopathy were included in our study. Multiple myeloma patients were further subdivided into two groups. Group A consisted of patients with low and intermediate tumor burdens, while group B included patients with high tumor mass. B- and T-cell subset analysis revealed an abnormal ratio between B/T and OKT4+/OKT8+ lymphocytes compared to healthy controls. These alterations were especially prominent in group B multiple myeloma. Immunoglobulin synthesis was studied in pokeweed-mitogen-stimulated lymphocyte cultures. The results indicate that the failure to synthesize and secrete immunoglobulin resides within the B-cell lineage and is probably due to a functional B-cell defect. T-cell immunoregulatory functions seem to be unaffected in both multiple myleoma and benign monoclonal gammopathy patients.

Hypogammaglobulinemia and hemophagocytic syndrome associated with lymphoproliferative disorders

Four patients with lymphohistiocytic disorders had or subsequently experienced severe hypogammaglobulinemia and pancytopenia due to hemophagocytosis. The percentages of B- and T-lymphocytes and the ratios of helper (OKT4) cells to suppressor (OKT8) cells in the peripheral blood were variably altered. Mitogenic response to pokeweed mitogen and phytohemagglutinin was depressed but could be restored to near normal by the in vitro addition of indomethacin or interleukin-2. The half-life of intravenously administered immunoglobulin was markedly shortened. The data indicate that hyperactive monocytes/histiocytes are capable of simultaneously ingesting apparently normal blood cells and immunoglobulin, leading to pancytopenia and hypogammaglobulinemia. The monocytes with suppressor activity (which could be abrogated with indomethacin or interleukin-2) appeared to additionally contribute to the hypogammaglobulinemia, possibly by interfering with the terminal differentiation of the B-lymphocytes. Hemophagocytosis occurs frequently in histiocytic and occasionally in lymphoproliferative disorders or viral diseases. More frequent and serial determination of serum immunoglobulin levels in such situations may lead to the discovery of additional cases.

Multiple myeloma associated with immune thrombocytopenic purpura

Thrombocytopenia in patients with multiple myeloma is usually due to chemotherapy or marrow replacement with myeloma cells. Two patients with multiple myeloma who fulfilled criteria for the diagnosis of immune thrombocytopenic purpura are presented. The etiologic and therapeutic implications of this unusual association are discussed.

B-cell activation in human plasma cell dyscrasias

We studied the abnormal in vitro polyclonal B-cell activity observed in patients with multiple myeloma and Waldenström's macroglobulinaemia. Numbers of cells spontaneously secreting immunoglobulin (Ig) in freshly isolated suspensions of peripheral blood mononuclear cells and pokeweed mitogen (PWM) stimulated cultures of blood mononuclear cells were determined with a protein A reverse haemolytic plaque assay. These data were correlated with both the clinical and laboratory parameters of disease. Furthermore, Ig secreted into supernatants of PWM-stimulated cultures was examined by a light chain radioimmunoassay for evidence of in vitro activation of malignant B-cells. The mean level of circulating immunoglobulin secreting cells (IgSC) in patients was elevated when compared to that of normal subjects. The highest values were observed in those patients with the highest levels of serum paraprotein. However, experiments with cycloheximide suggested that such increased circulating IgSC values were often caused by the detection of Ig passively adsorbed to blood mononuclear cells. The studies with PWM stimulation of blood mononuclear cells were particularly revealing. Cultures of patient blood mononuclear cells with PWM showed depressed IgSC responses as a group compared to cultures of normal blood mononuclear cells; nevertheless, approximately half the patients demonstrated a sizeable response to PWM. No evidence for preferential activation of Ig secretion by the malignant B-cell clone was observed. Impaired PWM induced responses were associated with advanced or progressive clinical disease.

Specificity repertoire of lymphocytes from multiple myeloma patients. I. High frequency of B cells specific for idiotypic and F(ab')2-region determinants on immunoglobulin

The specificity repertoire of B lymphocytes from 14 multiple myeloma patients has been studied using the technique of Epstein-Barr virus (EBV) transformation of peripheral blood lymphocytes (PBL) coupled with clonal analysis by limiting dilution. We find that up to 100% of the B cells from myeloma patients undergoing EBV transformation secrete IgM specific for determinants on the F(ab')2 region of autologous and/or heterologous monoclonal immunoglobulin. In normal individuals 0.02-0.73% of the transformed B cells secrete IgM specific for F(ab')2 determinants. Two patients with monoclonal gammopathy of undetermined significance had only a weak reactivity to F(ab')2 fragments. The number of anti-F(ab')2 B cells was up to 145-fold greater in patients than in normal donors. The majority of antibodies from patient clones recognized determinants shared among 3-12 different F(ab')2 fragments, whereas those originating from normal donor B cells saw determinants expressed on only one or two of the panel of test F(ab')2 fragments. There was a preference for autologous M components and a high proportion of antiidiotypic reactivity in five of eight patients so analyzed. We speculate that these findings indicate the existence of an anti-F(ab')2 immunoregulatory network mediating patient immunodeficiency network mediating patient immunodeficiency, thereby creating an abnormality that may enable the progression of multiple myeloma.

Immunoglobulin-producing tumors

Multiple myeloma and macroglobulinemia are the most common immunoglobulin-producing neoplasms seen in the dog. Treatment with the alkylating agents in combination with prednisone may significantly prolong survival. Supportive management of associated complications is imperative to ensure that the individual case receives optimal care. The use of clinical staging seems to be of value in establishing prognosis; however, response to therapy may be more significant, for many dogs present with advanced disease. In the high-risk patient, one should consider using investigational combination drug protocols which are available at a referral center. Although a "cure" is unlikely, the prospect of the animal having a fairly normal, healthy life for an extended period of time (over a year in the majority of cases) should encourage veterinarians to recommend evaluation for treatment in dogs with multiple myeloma and macroglobulinemia.

Abnormal function of B lymphocytes from peripheral blood of multiple myeloma patients. Lack of correlation between the number of cells potentially able to secrete immunoglobulin M and serum immunoglobulin M levels

Multiple myeloma patients are deficient in normal polyclonal serum immunoglobulins. To determine the reasons for this decrease, we quantitated and compared the number of surface IgM+ B lymphocytes, and the number of B cells susceptible to transformation by Epstein-Barr virus (EBV) with the concentration of IgM in serum. Serum IgM levels varied considerably in individual patients, temporally shifting from undetectable to normal amounts and then dropping again to undetectable levels. A transient rise to normal serum IgM concentrations was seen in 42% of patients assessed at two or more time points. Of 44 patients, 52% showed a lack of correlation between the number of surface IgM+ (sIgM+) B cells and serum IgM concentration. One subset of patients (25%) had detectable to normal numbers of sIgM+ B cells in blood but undetectable levels of serum IgM. Transformation of B cells from these patients indicated a block in IgM secretion that was extrinsic to the B cells that were fully able to transcribe, translate, and secrete IgM after EBV transformation. A second subset of patients (27%) had undetectable numbers of sIgM+ B cells but near normal levels of serum IgM, suggesting abundant secretion by few clones of B cells. Of 18 patients with monoclonal gammopathy of undetermined significance (MGUS), 26% showed a lack of correlation between the numbers of sIgM+ B cells and serum IgM concentration. We suggest that in patients with multiple myeloma, and in some with MGUS, there exists a mechanism(s) extrinsic to the B cell that mediates an arrest in terminal B lymphocyte maturation.

Serum immunosuppressive acidic protein in adult T-cell leukaemia (ATL)

The availability of serum immunosuppressive acidic protein (IAP) as a marker of subtypes of adult T-cell leukaemia (ATL) was examined. Serum IAP levels were measured in 34 patients with ATL (18 typical, 9 atypical and 7 smoldering), 7 healthy carriers of ATLA antibody and 53 healthy controls. The mean value of serum IAP was significantly higher in patients with typical ATL (897.8 +/- 502.4 micrograms/ml) than in those with atypical ATL (426.7 +/- 106.6 micrograms/l), smoldering ATL (310.0 +/- 51.3 micrograms/ml), healthy carriers of ATLA antibody (302.9 +/- 39.5 micrograms/ml) and normal controls (350.5 +/- 73.2 micrograms/ml). Serial determinations of IAP revealed that the level was correlated with the clinical course in patients with ATL; there was a difference in the prognosis of patients with high and normal levels of IAP (P less than 0.05). Thus, routine measurement of serum IAP seems useful in differentiating typical, atypical and smoldering ATL and also in evaluating the prognosis of patients.

Effect of chemotherapy on T-lymphocyte subsets in B-cell proliferative disorders

The T-cell subset distribution and the activity markers of 41 patients with multiple Myeloma, Waldenström's macroglobulinaemia and benign monoclonal gammopathy were repeatedly analysed using monoclonal antibodies (T3, T4, T8, anti-TAC, anti DR) and rosetting techniques. In myeloma and macroglobulinaemia the relative and absolute numbers of T4+ cells were diminished while the absolute number of T8+ cells was not decreased. No significant difference between stage I and III of the myeloma disease was seen. The diminished number of T4+ cells in myeloma was partly due to the effect of chemotherapy. Chemotherapy-induced lymphopenia resulted in a drop of circulating T4+ cells and an inverted T4/T8 cell ratio. Untreated patients with myeloma were not significantly different from patients with benign gammopathy. Patients with macroglobulinaemia differed from patients with myeloma as they had an increased absolute T8 cell count and a significantly elevated percentage of TAC+ (= IL 2 receptor expressing) cells. In macroglobulinaemia chemotherapy affected also the T8+ cell subset. Thus, patients with macroglobulinaemia, but not with myeloma appear to have activated T8+ cells in their circulation.

Serum anti-lipid A antibodies in multiple myeloma and Waldenström's macroglobulinaemia

Anti-lipid A antibodies were determined in sera from 38 patients with IgG multiple myeloma, 33 patients with IgA multiple myeloma and 38 patients with Waldenström's macroglobulinaemia using an enzyme-linked immunosorbent assay (ELISA). Compared to 34 healthy adults, significantly (p less than 0.025, p less than 0.005, p less than 0.0025) lower serum anti-lipid A antibody levels were measured for the respective patient groups. Low anti-lipid A antibody levels correlated with a higher infection rate with gram-negative bacteria in patients with monoclonal B-cell malignancies. The highest infection rate was seen in patients with simultaneous low anti-lipid A levels and secondary antibody deficiency.

Suppressor-cell functions in bullous pemphigoid

T Cells from 14 patients in the active stage of bullous pemphigoid and 10 patients in the inactive stage of the disease were studied with Leu-1, Leu-2, and Leu-3 monoclonal antibodies. The proportions of total T cells and T cells expressing either helper or suppressor phenotype in the peripheral blood of patients were not significantly different to those observed in normal subjects. In 15 patients with active disease, immunoregulatory mechanisms were functionally studied using an assay measuring the amount of total IgG synthesized in vitro. Peripheral-blood leukocytes were separated into T- and B-cell fractions, and cultured in various combinations. In ten experiments, prior to culturing with B cells, the T cells were irradiated to remove their suppressor function. No statistically significant differences were observed in the amount of total IgG synthesized by B cells obtained from patients and normal subjects when they were cultured with untreated T cells or irradiated T cells obtained from patients or normal controls. These results indicate that, in patients with bullous pemphigoid, there is no loss of suppressor-cell function or increased helper-cell function as assessed by measuring the total IgG synthesized. Therefore, the immunoregulatory defect, if present, is a highly specific one and can only be studied using antigen-specific assays.

Functions of polymorphonuclear (PMN) leukocytes of patients with lymphoproliferative diseases

PMN leukocytes from untreated patients with multiple myeloma (MM), Hodgkin's disease (HD) and non-Hodgkin lymphoma (NHL) were studied in vitro for their phagocytic and chemotactic function. Alkaline phosphatase score and the reduction of nitroblue tetrazolium (NBT) in these leukocytes were also determined. Most of the functions of PMN leukocytes from untreated patients with MM were impaired, compared to control leukocytes, while those from patients with HD and NHL were impaired only in their chemotactic response to casein and endotoxin-activated serum (EAS).

Granulocytopenia and cancer therapy. Past problems, current solutions, future challenges

Granulocytopenia has been closely associated with cancer and its treatment. The risk for a life-threatening infection when the granulocyte count falls below 500/mm3 not only is an important complication of therapy and a major cause of death in cancer patients but also plays an important role in the design, schedule, and doses of cancer treatment regimens. While granulocytopenia remains an unavoidable complication of current therapy, improved recognition of patients at risk and prompt initiation of aggressive supportive care have had a significant impact on reducing its infection-related morbidity and mortality. In particular, early empiric antibiotic therapy when the granulocytopenic patient becomes febrile has resulted in a significant reduction in the early mortality from undiagnosed bacterial infections. New antibiotics (extended-spectrum penicillins, third generation cephalosporins) provide new options because of their broad efficacy and potential for reducing the toxicity of antimicrobial therapy. However, as bacterial infections have become better controlled, fungi have emerged as important pathogens. Early aggressive empiric antifungal therapy appears to have reduced infectious mortality, although the repertoire of effective antifungal agents is quite limited. Considerable efforts have been expended in trying to replenish granulocytes by transfusion in infected patients, but technical deficiencies have limited this approach. Current and future efforts are directed toward refining management as well as to developing methods to improve host defenses and provide prophylaxis against infections. If the full potential of current cancer therapy is to be realized, control of granulocytopenia and the prevention of infections are essential goals.

The use of Staphylococcus aureus Cowan I for evaluation of suppressor-T-cell activity in hypogammaglobulinemia: evidence for two functionally distinct suppressor T cells

In coculture experiments with normal lymphocytes, peripheral blood lymphocytes (PBL) of 10 boys with hypogammaglobulinemia were screened for the presence of cells able to suppress Pokeweed mitogen (PWM)- and Staphylococcus aureus Cowan I-induced immunoglobulin production in vitro. PBL and T lymphocytes of two patients were shown to suppress reproducibly PWM-induced immunoglobulin production of control PBL and of control B + T lymphocytes. PBL of three other patients were also able to suppress but their activity was expressed only in combination with some but not other normal lymphocytes. In neither case was the Cowan I-induced response suppressed. PBL and T lymphocytes of one other patient were able to suppress both PWM- and S. aureus Cowan I-induced immunoglobulin production of normal lymphocytes. These data provide evidence for two functionally distinct suppressor T lymphocytes in hypogammaglobulinemic patients.

A study of certain functional parameters of monocytes from patients with multiple myeloma: comparison with monocytes from healthy individuals

Selected functions (i.e. phagocytosis and chemotaxis of circulating blood monocytes were studied on cells obtained from 20 patients with untreated multiple myeloma (MM) and the results were compared with those obtained on cells from 60 healthy persons. The mean number of circulating monocytes was only slightly increased over the normal value although a marked monocytosis was demonstrated in all of the 4 patients with M-components of the lambda light chain type. Plasma cells isolated from peripheral blood and from bone marrow of patients with MM were found to possess a strong alpha-naphthyl acetate esterase activity. No differences were observed in the phagocytic activity of monocytes from patients compared with those of the controls, whereas the chemotactic responsiveness of the monocytes from the patients was slightly increased.

Monocyte suppression of Fusobacterium nucleatum-induced human polyclonal B-lymphocyte activation

Previous studies reported that Fusobacterium nucleatum induced polyclonal B-lymphocyte activation (PBA) as determined by immunoglobulin M production in cultures of human peripheral blood mononuclear cells. However, the PBA response was greatly enhanced when the cells were depleted of esterase-positive, adherent cells (i.e., monocytes). The purpose of this study was to confirm and further examine the suppression of F. nucleatum-induced PBA (F. nucleatum-PBA) by blood monocytes. For comparison, PBA induced by pokeweed mitogen (PWM-PBA), which is enhanced by monocytes, was assessed in some experiments. We found the removal of monocytes from unfractionated cells by (i) Sephadex G-10, (ii) anti-monocyte specific OM-1 monoclonal antibody plus complement, or (iii) L-leucine methyl ester, a compound which selectively kills lysosome-rich cells, resulted in a population of cells responsive to F. nucleatum-PBA and unresponsive to PWM-PBA. The addition of double adherence-purified monocytes (greater than 85% esterase-positive cells), particularly in concentrations of greater than 10%, to lymphocytes depleted of monocytes by G-10, OM-1, or L-leucine methyl ester treatments, suppressed F. nucleatum-PBA and enhanced PWM-PBA. Monocytes also suppressed a mixture of isolated T and B cells combined in a T/B cell ratio of 3:1, which is an optimal ratio for F. nucleatum-PBA. Allogeneic monocytes suppressed F. nucleatum-PBA, although at low numbers these cells were not as suppressive as autologous monocytes. Heating at 56 degrees C for 15 min, sonicating, or freeze-thawing the monocyte preparations resulted in an abrogation of monocyte-induced suppression of F. nucleatum-PBA. Kinetic studies in which fresh monocytes were added daily to lymphocytes stimulated with F. nucleatum or PWM showed that the monocytes must be added within the first 2 days of culture to suppress F. nucleatum-PBA or enhance PWM-PBA. Monocytes incubated with F. nucleatum for 48 h released into the culture medium a soluble factor that suppressed F. nucleatum-PBA. The results from this study demonstrate a potent mechanism by which the host might prevent exaggerated nonspecific immunoglobulin responses when exposed to PBA-inducing concentrations of F. nucleatum. On the other hand, the induction of suppressive monocytes (or monocyte-mediated suppressive factors) by interaction with F. nucleatum might result in the inhibition of host protective immune reactions.

Light chain isotype associated suppression of surface immunoglobulin expression on peripheral blood lymphocytes in myeloma during plateau phase

Light chain isotype suppression in multiple myeloma has been reported in the plasma cells of the lamina propria of the gut (Leonard et al, 1979). In this paper we present further evidence of systemic suppression of the light chain isotype of the paraprotein expressed on normal peripheral blood lymphocytes in myeloma. Twenty patients with myeloma in plateau phase were monitored over 6 months for the expression of either kappa or lambda light chains on the surface of peripheral blood lymphocytes using monoclonal antibodies. The surface markers were analysed on an Ortho Spectrum III flow cytometer. Results of these studies indicate a selective suppression of the cells expressing the light chain isotype of the paraprotein in stable myeloma. Thus, in kappa myeloma there is a low kappa/lambda ratio and in lambda myeloma there is a high kappa/lambda ratio, and this suppression is lost with progressive disease.

Synthesis of electrophoretically restricted IgG by cultured rheumatoid synovium

IgG synthesized by excised rheumatoid (RA) synovia was separated according to isoelectric point using chromatofocusing and isoelectric focusing. Over 30% of the IgG synthesized by 9 of 11 synovia had an isoelectric point greater than 8 (cathodal shift), while 55% of the synovia secreted IgG showing oligoclonal banding by isoelectric focusing. Oligoclonal serum IgG was seen in 17% of RA patients and in only 3% of hospitalized patients without RA. These results emphasize the selective character of the antigenic stimulus of the RA synovial lymphoid infiltrate.

Increased concanavalin A induced suppression in treated and untreated coeliac disease

The generation of suppression by concanavalin A in peripheral blood mononuclear cells in treated and untreated coeliac subjects using an in vitro assay was found to be significantly increased when compared with controls. The response of peripheral blood mononuclear cells to the plant mitogen concanavalin A (con A) was also significantly depressed in both groups of coeliac patients. It is proposed that the depressed cell mediated immunity found in this and other studies in coeliac patients is because of increased suppression. The possible connection between these findings and the increased incidence of malignancy also found in coeliac disease is discussed.

Multiple myeloma

Multiple myeloma is a malignant neoplasm of plasma cells involving bone and bone marrow, frequently leading to extensive skeletal destruction, bone marrow failure, renal dysfunction, and problems related to the monoclonal myeloma proteins. Vigilant supportive care and effective chemotherapy can prolong survival and improve the quality of life in most patients.

Decreased T lymphocyte migration in patients with malignancy mediated by a suppressor cell population

The migration and concentration of lymphocytes at sites of antigenic challenge are an integral part of the expression of delayed cutaneous hypersensitivity, as well as of tumor and graft rejection. In this study, we have analyzed the migration of T lymphocytes from patients with malignancy. We used casein and concanavalin A (Con A)-stimulated mononuclear cell supernatants to stimulate T cell locomotion. Peripheral blood T lymphocytes from 30 patients with established malignancy, 10 patients with indolent malignancy or benign tumor, and 42 normal adult controls were tested. Data are expressed as a migration index (MI), which represents the difference in micrometers between the distance migrated in response to a stimulus and the distance migrated in response to media alone. We observed a marked depression in casein-stimulated T lymphocyte migration in patients with established malignancy (mean MI +/- 1 SD = 17.0 +/- 9 microns) as compared with normal adult controls (mean MI +/- 1 SD = 35.3 +/- 10 microns). Similar results were observed with migration in response to Con A supernatants. T cells from patients with established malignancy had a mean MI of 5.8 +/- 4 microns to Con A supernatants as compared with 24.5 +/- 5 for controls. This depressed migration was apparent both in the distance that cells migrated and in the number of cells that migrated into the membrane. Of 10 patients with indolent malignancy or benign tumor, T cell migration in 8 was not significantly decreased as compared with controls. When we mixed equal concentrations of normal control T lymphocytes with T lymphocytes from patients with cancer and added the mixture directly to the upper compartment of the chemotaxis chamber, the response of the normal T cells to casein was inhibited by an average of 48%. We observed inhibition of this migration of normal cells when we added as little as 10% of patient cells to normal cells. When we mixed normal control T lymphocytes from different donors and added them directly to the upper compartment of the chemotaxis chamber, T lymphocyte migration in response to casein was not significantly altered. If T cells from patients with cancer were cultured overnight, the suppressive effect on lymphocyte locomotion was lost. Our results indicate that there is a population of T lymphocytes in patients with cancer that suppress normal T lymphocyte migration. This suppressor activity may partially explain the subversion of immunosurveillance in established neoplastic states, as well as the defective inflammatory reaction to intradermal injection of antigen observed in many patients with malignancy.

Phase I study of intravenous gamma globulin in multiple myeloma

Seventeen patients with multiple myeloma were given intravenous immunoglobulin at doses ranging from 150 mg/kg to 500 mg/kg in a phase I study. The intravenous immunoglobulin was well tolerated with only three transient episodes of mild clinical toxicity during 27 infusions. In no instance was hepatic or renal toxicity seen. Marked biologic variability over the one month study period in total IgG levels in patients with non-IgG myeloma and IgG subclasses in many of the patients was observed, making intravenous immunoglobulin half-life determinations based on IgG or IgG subclass levels problematical. The decay of functional antibody to hepatitis B surface antigen was determined. Analysis of the hepatitis antibody data suggested that intravenous immunoglobulin half-life was in the range of seven to 20 days for the entire study group and was not related to the isotype of the myeloma paraprotein or to the baseline levels of IgG. No infections were observed in the study group during the study period, but the potential for infection prophylaxis by intravenous immunoglobulin in myeloma patients must be evaluated in a randomized, prospective, controlled phase III study.

Monoclonal antibody-defined T-cell phenotypes and phytohemagglutinin reactivity of E-rosette-forming circulating lymphocytes from untreated chronic myelocytic leukemia patients

T-cell phenotypes, as defined by murine monoclonal antibodies, (OKT3, OKT4, OKT8, OKIa1), and phytohemagglutinin (PHA) reactivity, were evaluated in E-rosette forming cells (T-cells) from 10 untreated chronic myelocytic leukemia patients. The proportion of T4+ cells was lower in patients than in controls (41.6 versus 61.7%, P less than 0.02); whereas the proportion of T8+ cells was similar in patients and controls. The decrease in T4+ cells in CML resulted in a decrease in circulating T4+/T8+ ratio (P less than 0.02). The Ia1+ T-cells were increased in most CML (8 of 9) patients, while control subjects never displayed Ia1+ T-lymphocytes (P less than 0.01). The PHA reactivity of E-rosette forming lymphocytes was significantly impaired in CML patients with respect to controls (P less than 0.02). The presence of Ia antigen on T-cells was positively correlated with the T8+ cell phenotype (P less than 0.001) and inversely correlated with the T4+ (helper) cell phenotype (P less than 0.05). Furthermore, there was a trend towards an inverse correlation between the PHA response and the level of Ia1+ or T8+ cells, there is no correlation between PHA reactivity and T4+ phenotype. The results suggest that the T-lymphocyte population from untreated CML patients is intrinsically abnormal.

In vitro immunoglobulin production by peripheral blood mononuclear cells from multiple myeloma patients and patients with benign monoclonal gammopathy. Regulation by cell subsets

Peripheral blood mononuclear cells (PBM) from four patients with IgG myeloma and four patients with benign monoclonal gammopathy (BMG) were stimulated with pokeweed mitogen (PWM), and the in vitro immunoglobulin production over 7 days was measured with an enzyme-linked immunosorbent assay. All myeloma patients were sufficiently treated with cytostatic drugs. Their PBM did not produce monoclonal Ig in vitro, as opposed to PBM from two patients with BMG. Unseparated PBM from myeloma patients produced smaller amounts of polyclonal Ig than unseparated cells from normal donors. However, macrophage-depleted PBM from myeloma patients produced amounts of Ig comparable to those of normal donors when autologous or allogeneic adherent cells were returned in defined numbers. T cells from three of the four myeloma patients could provide help for the Ig production by B cells from healthy donors. These results indicate that functionally normal polyclonal B cells circulate in the blood of myeloma patients. The circulating T-cell population also has no obvious defect. In contrast, blood macrophages seemed to be altered with respect to their regulating function for polyclonal Ig production. The results obtained by using cell populations from patients with BMG did not differ from those of healthy people.

Synovial fluid and blood monocytes/macrophages in rheumatoid arthritis. Influence on polyclonal activation of autologous B lymphocytes

The regulatory role of synovial fluid monocytes/macrophages from patients with rheumatoid arthritis in terms of B lymphocyte activation was evaluated by a reverse haemolytic plaque-forming cell (PFC) assay. Macrophage-depleted blood mononuclear cells (BMC) failed to respond to pokeweed mitogen (PWM). With autologous synovial fluid macrophages added, the PFC responses of macrophage-depleted BMC increased, and optimal concentration for full restoration of the PFC responses ranged from 8 to 35%. Synovial fluid mononuclear cells (SMC) as well as macrophage-depleted SMC were not able to respond to PWM. Addition of irradiated autologous blood macrophages to SMC did not increase the SMC PFC responses. It is concluded that the regulatory properties of synovial fluid macrophages do not explain the low PFC response of SMC to PWM.