Role of suppressor T cells in pathogenesis of common variable hypogammaglobulinaemia

Autoimmune hemolytic anemia as a manifestation of T-suppressor-cell deficiency

This report describes two children in whom autoimmune hemolytic anemia was the initial clinical manifestation of an underlying T-cell deficiency. Further investigation revealed a profound deficiency of T suppressor cells in both children as detected by monoclonal T-cell antibody (OKT8) and/or functional assays. In vitro incubation of their lymphocytes with cultured thymus epithelium or thymic factors induced T suppressor cells. In vivo treatment with cultured thymus epithelium or calf thymosin fraction 5 resulted in increased T-suppressor-cell numbers and/or function in both and possibly decreased hemolytic activity in one. These results suggest that the autoimmune process in some patients with autoimmune hemolytic anemia is associated with T-suppressor-cell deficiency and that in vivo therapy with agents that modulate T-cell function may be of therapeutic value.

Diagnostic importance of immunological markers in lymphoma involving the central nervous system

In an elderly woman, lymphoma involved the central nervous system and unusual nonlymphoreticular sites. Cerebrospinal fluid cell surface marker studies revealed a clone of malignant B cells. Studies of peripheral blood demonstrated a systemic disturbance of immune regulation similar to Epstein-Barr virus infections and the acquired immunodeficiency syndrome.

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.

Polyclonal immunoglobulin secretion in patients with common variable immunodeficiency using monoclonal B cell differentiation factors

B cells from 25 patients with common variable immunodeficiency (CVI) were tested for their ability to differentiate under the influence of B cell differentiation factors (BCDF), derived from T cell hybridomas or T cell clones. 11 patients generated Ig plaque-forming cells in the range comparable to that of normal controls with supernatant from the T cell hybrid MOP 1L. With various hybrid or clone supernatants, differing response patterns emerged. Four patients who failed to respond to MOP 1L responded to T cell clone supernatant RAC. Another who failed to respond to both MOP 1L and RAC responded to T cell hybrid supernatant MTP 7. These results indicate that these supernatants contain different BCDFs and suggest heterogeneity in the differentiation states of B cells in CVI. In addition, three patients demonstrated exaggerated responses to BCDF, and evidence was obtained from B cells of these patients for increased BCDF receptor density. Thus, the accumulated evidence indicates that T cell defects may be a primary pathogenetic mechanism in common variable immunodeficiency, and purified BCDF may be of therapeutic value.

Expression of interleukin 2 receptors on activated human B cells

Using anti-Tac, a monoclonal anti-interleukin 2 (IL-2) receptor antibody, we have explored the possibility that certain activated B cells display receptors for IL-2. Resting normal B cells and unselected B cell lines established from normal individuals were Tac antigen negative. In contrast, the cell surface Tac antigen expression was demonstrable on 6 of 10 B cell lines from patients with Burkitt's lymphoma, 5 of 6 B cell lines derived from patients with HTLV-I-associated adult T cell leukemia (including all four that had integrated HTLV-I into their genome), and on certain normal B cells activated with pokeweed mitogen. Furthermore, cloned Epstein-Barr virus-transformed B cell lines derived from Tac-positive normal B cells continued to express the Tac antigen in long-term cultures and manifested high affinity IL-2 receptors identified in binding studies with purified radiolabeled IL-2. The line 5B4 developed in the present study could be induced with purified JURKAT-derived or recombinant IL-2 to express a larger number of IL-2 receptors. Furthermore, the addition of IL-2 to the 5B4 B cell line augmented IgM synthesis, which could be blocked by the addition of anti-Tac. The size of the IL-2 receptors expressed on the cloned normal B cell lines was similar (53,000-57,000 daltons) to that of receptors on phytohemagglutinin-stimulated T cell lymphoblasts. Thus, certain malignant and activated normal B cells display the Tac antigen and manifest high affinity receptors for IL-2. These data suggest that IL-2 may play a role in the differentiation of activated B cells into immunoglobulin-synthesizing and -secreting cells.

Long-term survival after bone marrow transplantation: a 15-year follow-up report of a patient with Wiskott-Aldrich syndrome

In 1968 a 2-year-old boy with Wiskott-Aldrich syndrome was extremely ill with eczema, a series of life-threatening infections, and repeated hemorrhages into his skin, lungs, brain, and other internal organs. He was given high-dose cyclophosphamide therapy for immunosuppression, followed by bone marrow cells from his histocompatible, healthy sister. In the 15 years since bone marrow transplantation, he has had full T cell, partial B cell, and no hematopoietic engraftment. He has weathered the usual infectious diseases of childhood, has had no serious infections, and despite persistent thrombocytopenia has not had serious bleeding episodes.

Acquired hypogammaglobulinaemia and sarcoidosis

A syndrome has been described in which hypogammaglobulinaemia is associated with splenomegaly and haemolytic anaemia and also non-caseating granulomata in lymph nodes, liver, spleen and skin. This report describes a patient with this syndrome who in addition had a positive Kveim and elevated serum angiotensin converting enzyme (SACE), suggesting the diagnosis of sarcoidosis.

Identification of B-cell and T-helper-cell defects, and of suppressor cell hyperactivity, in humoral immunodeficiency

Methods are described for distinguishing between intrinsic B-cell defects, T-helper-cell defects, and suppressor cell hyperactivity in patients who fail to secrete immunoglobulin when peripheral blood mononuclear cells are stimulated with pokeweed mitogen. Control cells which respond to pokeweed mitogen are made unresponsive by depleting B cells or OKT4+ cells, and the missing subset, purified from the patient's peripheral blood mononuclear cells, is added back to examine its functional activity. Alternatively, hyperactivity of OKT8+ putative suppressor T cells or suppressor monocytes is evaluated by depleting these populations from the patient's peripheral blood mononuclear cells. Four patients who produced few plaque-forming cells in response to pokeweed mitogen were investigated: two had intrinsic B-cell deficiencies, one had T-helper-cell deficiency, and one had T-suppressor-cell hyperactivity.

IgA deficiency during treatment of infantile hypothyroidism with thyroxine

Serum IgA concentrations in five children with infantile hypothyroidism fell soon after the start of treatment with thyroxine. In one child the IgA concentration fell appreciably (to less than 0.01 g/1) and remained reduced; in the four others it returned to normal. IgM and IgG concentrations were roughly normal throughout. The deficiency in IgA concentrations may have been due to stimulation by thyroxine treatment of a T cell suppressor system that, in the original hypothyroid state, was less than normally active.

Mononuclear-cell subsets in human idiopathic crescentic glomerulonephritis (ICGN): analysis in tissue sections with monoclonal antibodies

Mononuclear inflammatory cells (MIC) were analyzed in renal biopsies from 16 patients with ICGN (7 with glomerular immune complex deposits, 3 with anti-GBM disease, and 6 without immune deposits) by the avidin-biotin-immunoperoxidase technique utilizing monoclonal antibodies to cell surface antigens: T11 (total T), T4 (inducer/helper T), T8 (suppressor/cytotoxic T), B1 (B cells), M1 (monocytes/granulocytes), and Leu 7 [natural killer (NK) cells]. Total MIC were significantly increased in both glomeruli and interstitial tissues of the patients. Interstitial MIC consisted mainly of lymphocytes (80%) and monocytes (19%), with small numbers of B and NK cells present. In contrast, MIC in renal glomeruli of patients with ICGN were composed of monocytes (65%) rather than T lymphocytes (34%). A majority of T lymphocytes found in renal tissues of patients and controls had the helper/inducer phenotype. Tissue T4/T8 ratios were not significantly different in the glomeruli and interstitium. Monocytes and T lymphocytes accumulating in renal tissues of patients with ICGN may mediate glomerular injury in all forms of human ICGN.

Regulation of B cell activation and differentiation with factors generated by human T cell hybridomas

Human T cell hybridomas were generated by several techniques and the supernatants generated were screened for activity on human B cells. Three general activities were noted; B cell proliferation factor ( BCPF ), B cell differentiation factor (BCDF), and an IgA isotype-specific helper factor. BCPF acts on B cells to induce proliferation without differentiation and is distinct from conventional BCGF. This was documented by BCPF 's inability to synergize with anti-mu Ab in a standard BCGF assay ( Muraguchi & Fauci 1982, Howard et al. 1982, Sieckman et al. 1981), as well as its differential effect on a leukemic B cell preparation, when compared with BCGF. A possible schema for BCPF activity is depicted in Figures 3 and 4. In Figure 3, BCPF acts like Ag in vivo or like anti-mu in vitro, pre-activating B cells and rendering them responsive to BCGF. Figure 4 represents what our data depict, that is that BCPF bypasses the response to BCGF and induces cells to proliferate without pre-activation. The difference in the 2 mechanisms may be concentration-dependent and this possibility is currently being evaluated. It is interesting to speculate that T cells in vivo are capable of initiating B cell activation and may account for polyclonal responses seen with some Ag-specific reactions. BCDF(s) act on post-activated B cells (Figure 3) to induce differentiation to Ig-secreting cells. They appear to be heterogeneous and, therefore are capable of inducing varied responses depending on the B cell subpopulation affected. Figure 3 is deliberately complex demonstrating some of the possible as well as documented BCDF activities including polyclonal differentiation and isotype specific activity in IgA committed B cells. We cannot be certain of the frequency of these BCDF-secreting T cells, but the studies of cells from patients with common variable immunodeficiency and chronic lymphocytic leukemia have helped to dissect out these activities. These data would suggest that these BCDF subgroups are important, as deficiencies in one or more subgroups may result in disease.

A flow cytometric technique for quantitation of B-cell activation

A flow cytometric method for enumeration of intracytoplasmic antibody-containing cells was developed. Flow cytometry was found to yield results comparable to traditional fluorescence microscopy in cells stimulated to produce intracytoplasmic antibody by either pokeweed mitogen or Epstein-Barr virus. This technique offers several advantages over traditional fluorescence microscopy, including objective measurement of fluorescence intensity and rapid analysis of large numbers of cells.

Enumeration of human immunoglobulin-secreting cells by the ELISA-plaque method: IgE and IgG isotypes

A new system is described for the enumeration of human immunoglobulin-secreting cells (ISC), based upon the ELISA methodology. In principle, putative ISC are incubated over a solid phase containing bound anti-Ig of the isotype being tested. Secreted Ig is immobilized at or near the point of release from the ISC, and the resulting Ig fingerprint of the ISC is then visualized by the sequential application of an anti-Ig-alkaline phosphatase conjugate, followed by a substrate-agarose overlay. The system is capable of detecting IgE-secreting cells, and pokeweed mitogen-stimulated IgG-secreting cells with sensitivity at least equivalent to the protein A hemolytic plaque assay.

Detection of IgG in supernatants of pokeweed mitogen-stimulated human lymphocyte cultures by one step solid-phase radioimmunoassay (SPRIA)

A one step solid phase radioimmunoassay is used as a simple and reproducible method of detection and quantitation of IgG produced by human PBL after stimulation with PWM. Modifications of culture conditions are necessary to make culture supernatants suitable for this assay. Pulsing with PWM must be performed in serum-supplemented culture medium for 4-5 days. After thorough washing, medium is then replaced with serum-free medium. Under these conditions, synthesis and secretion of IgG continues for at least 9 days. The amount of IgG produced by 10(6) normal adult PBL as detected in this system is 0.77 +/- 0.47 micrograms. No close correlation between cell proliferation and IgG synthesis was observed.

Excessive numbers and activity of peripheral blood B cells in infants with Chlamydia trachomatis pneumonia

The peripheral blood lymphocytes of seven infants who had lower respiratory infections caused by Chlamydia trachomatis (chlamydial pneumonia) were studied for abnormalities that may be related to the hyperimmunoglobulinemia characteristic of this infection. Both proportions and numbers of B cells and plasma cells were strikingly elevated in these infants, as indicted by the percentage of peripheral blood mononuclear cells (PBMC) that reacted with fluorochrome-labeled antibodies to human immunoglobulins. Cells expressing IgM and IgD on their surface, and cells possessing IgM and IgG in their cytoplasm were especially increased above levels found in normal adults, infants, and a group of infants with other infections. Cells from infected infants secreted exceptionally large amounts of IgM, IgG, and IgA when cultured in the absence of added mitogens. These data suggest that chlamydial pneumonia induces substantial B-cell activation during a period of development when antibody responses are normally difficult to stimulate.

The regulatory roles of T4 and T8 subsets in tetanus toxoid-induced in vitro immunoglobulin production

A new mitogenic system for in vitro immunoglobulin production induced by tetanus toxoid is presented and the role of T4 and T8 subsets in tetanus toxoid-induced in vitro immunoglobulin production is investigated. Purified T, T4, T8, and B cells from normal individuals previously immunized but not boosted with tetanus toxoid were cultured in helper and suppressor assays and the number of immunoglobulin-secreting cells were enumerated after culture using a hemolytic plaque assay. The regulatory roles of T4 and T8 cells in this tetanus toxoid system were compared with the role of these subsets after pokeweed mitogen stimulation. Although most of the immunoglobulin produced in the tetanus toxoid system was polyclonal, there were differences in the time course, the magnitude of the responses, the radiosensitivity of the subsets, and optimal T- to B-cell ratios for immunoglobulin production which distinguish the tetanus toxoid and pokeweed mitogen systems.

Hyper IgM immunodeficiency. A primary dysfunction of B lymphocyte isotype switching

Immunological evaluations (lymphocyte markers, B cell differentiation, T cell function) were performed on peripheral blood mononuclear cells from four individuals with hyper IgM immunodeficiency. Number, proportion, and proliferation of T lymphocytes and T lymphocyte subpopulations were relatively normal in affected individuals. The percentage and number of B cells expressing surface IgM and IgD were either normal or elevated in both blood and lymph nodes. However, surface IgG- and IgA-bearing B lymphocytes were completely absent. In vitro stimulation of blood lymphocytes with both T cell-dependent and T-cell independent polyclonal B cell activators resulted in normal numbers of IgM plasma cells and IgM secretion in cultures, but failed to induce any IgG- or IgA-producing cells. This failure of isotype switching was intrinsic to the B cell population and did not involve aberrant T cell help or suppression. Therefore, individuals with this disorder possess an intrinsic B cell dysfunction that is not related to abnormal T cell regulation.

Characterization of the suppressor activity in lymphocytes from patients with common variable hypogammaglobulinemia: evidence for an associated primary B-cell defect

The pathogenetic mechanisms responsible for the impaired immunoglobulin production in common variable hypogammaglobulinemia (CVH) are diverse with abnormalities in both B cells and immunoregulatory T cells. Production of IgG, IgM, and IgM-rheumatoid factor (IgM-RF) was measured in pokeweed mitogen (PWM) or Epstein-Barr virus (EBV)-stimulated cultures using various combinations of CVH, cord blood mononuclear cells (CBMC), and normal adult control B and T cells. The following results were obtained. First, the proportion of OKT3+ and OKT8+ cells were increased in CVH patients. Second, the T cells from four CVH patients and CBMC suppressed PWM-induced IgG, IgM, and IgM-RF production by normal B cells. Furthermore, major suppressor activity was found in the OKT8+ T-cell subpopulations in CBMC and three out of four CVH patients. There was no significant difference in relative suppression by OKT8+ cells from normal adults, CVH patients, or CBMC. However, in one CVH patient suppressor T cells were found in both OKT4+ as well as OKT8+ fractions. In the CVH patient with OKT4+ suppressor cells, X irradiation (1250 rads) abrogated suppressor activity and restored helper activity in the OKT4+ T-cell fraction. Irradiation of normal OKT4+ cells did not increase helper activity. When non-E-rosetting cells from normal subjects, CVH, and CBMC were stimulated with EBV it was observed that normal adult B cells could be induced to secrete IgG, IgM, and Ig-RF whereas CVH and CBMC could only produce IgM and IgM-RF but not IgG. The present study demonstrates for the first time that a radiosensitive OKT4+ suppressor cell is present in some CVH patients.

Plaque-forming cells in man. II. Evidence of the existence of active suppressor cells in peripheral blood of normal plaque-forming cell non-responders

When the immunoglobulin secretion of 172 normal healthy individuals was investigated with the protein-A plaque assay, 12 persons (7%) did not develop any plaque-forming cells (PFC) in cultures of pokeweed mitogen (PWM)-activated unfractionated peripheral blood lymphocytes (PBL), incubated for 6 days. The effect of irradiation on normal PFC responders and non-responders was also investigated; 2000-rad-irradiated non-responder T lymphocytes co-cultured with autologous untreated B lymphocytes restored the PFC response to normal levels. The evidence of a high level of suppressor activity in non-responder T lymphocytes was further demonstrated by the decreased PFC response of normal B lymphocytes co-cultured with untreated non-responder T lymphocytes.

Suppressor cell function and T lymphocyte subpopulations in peripheral blood of patients with progressive systemic sclerosis

Three different in vitro assays--immunofluorescence with monoclonal anti-T cell reagents, enumeration of T gamma cells, and nonspecific suppressor cell function--were used for the analysis of suppressor lymphocytes in the circulation of 28 patients with progressive systemic sclerosis (PSS, scleroderma) and 20 normal individuals. Both OKT8+ and T gamma lymphocytes were significantly reduced (P less than 0.001 and P less than 0.02, respectively) in patients with PSS compared with controls. The OKT4/OKT8 ratio was increased (P less than 0.02). However, the mean suppressor cell index (SCI) of 1.9 (range 0.4-6.6) for patients with PSS was not significantly different (P greater than 0.05) from the SCI of 2.9 (range 1.2-14) for controls. Eleven of the patients had depressed suppressor cell function as indicated by the index value of less than 1.2. In only 5 of these patients, simultaneously measured T gamma and OKT8+ cells were reduced and OKT4+ lymphocytes were concomitantly increased. There were no significant correlations between the numbers of T gamma or OKT8+ cells and the SCI in patients and controls. Neither depressed suppressor cell function nor the OKT4+/OKT8+ ratio greater than 4.2 (greater than 2 SD of normal) in the patients could be related to other immunologic findings, to disease duration and severity, or to involvement of internal organs. These results suggest that depressed suppressor cell activity and immunoregulatory T cell imbalance in PSS may not be directly related to the pathogenesis of the disease.

Characterization of rhesus macaque peripheral blood T-lymphocyte subpopulations

Highly enriched rhesus macaque (Macaca mulatta) peripheral blood T-lymphocytes were separated into functional subpopulations by Fc-receptors. The T-lymphocyte population was comprised of both Fc-IgM (T mu +, 3.4 +/- 1.6) and Fc-IgG (T gamma +, 16.2 +/- 4.0) bearing cells. T-cells depleted of cells bearing Fc-IgG receptors (T gamma -) and T gamma + subpopulations were characterized and assessed for functional activity. T gamma + and T gamma - subpopulations were found to have the following characteristics: 1) T gamma + cells were stimulated by concanavalin-A (Con-A)3, pokeweed mitogen (PWM), and phytohemagglutinin-P (PHA-P), while T gamma - cells were stimulated by Con-A and PWM, but not PHA-P; 2) T gamma - cells were found to mediate PWM induced differentiation of autologous B-cells including EAC+ and EAC- enriched subpopulations, while T gamma + cells did not induce differentiation; 3) T gamma + cells released soluble factors which depressed mitogen stimulation of T gamma- cells; and 4) approximately 8-10% of the T gamma + cells phagocytized IgG sensitized bovine red blood cell (BRBC) immune complexes.

Epstein-Barr virus-induced immunoglobulin synthesis by B cells from individuals with late-onset panhypogammaglobulinemia

Epstein-Barr virus (EBV) transformation was used to examine the differentiation potential of circulating B cells from eight individuals with late-onset panhypogammaglobulinemia. Cytoplasmic and secreted immunoglobulins were evaluated by immunofluorescence and radioimmunoassay. EBV-infected cultures of B cells from patients and healthy controls generated similar numbers of IgM-secreting plasma cells, but relatively few IgG and IgA plasma cells were induced in cultures of patients' B cells. As further evidence of B-cell immaturity, approximately 90% of the IgA B cells in the eight patients coexpressed IgM. Clonal diversity of B cells from hypogammaglobulinemic patients was examined with a panel of mouse monoclonal antibodies directed against idiotypic and VH subgroup determinants. The frequencies of EBV-induced plasma cells exhibiting the different idiotypic and VH determinants were similar for patients and controls. The data suggest the continued generation of clonally diverse B cells that are capable of terminal plasma-cell differentiation when the normal triggering mechanisms are bypassed by EBV. The arrested differentiation at an immature B-cell stage in these hypogammaglobulinemic individuals would appear to reflect a defect in normal B-cell triggering.

T-cell subsets in human lymphocytes maintained in IL-2 medium after PHA or mixed lymphocyte reaction activation

The culture of human T lymphocytes in interleukin-2 (IL-2) containing growth factor medium results in a significant shift in the T-lymphocytes subsets isolated from such cultures at weekly intervals. If normal peripheral blood mononuclear cells are stimulated with phytohemagglutinin (PHA) or in a mixed lymphocyte reaction (MLR), the resulting T lymphoblasts can be propagated in growth factor medium. Staining of the cultured cells with monoclonal antibodies was evaluated by indirect immunofluorescence on a laser-activated flow cytometer (Ortho Spectrum III). The antibodies used were: OKT3 (mature T lymphocytes), OKT4 (helper/inducer T lymphocytes), OKT8 (cytotoxic/suppressor T lymphocytes, OKT10 (immature and "activated" lymphocytes), OKT11a (cells which rosette with sheep erythrocytes), and OKIa-I (HLA-DR constant region). Both PHA and MLR activation resulted in initial preservation of the OKT4+ subset predominance over OKT8+ T lymphocytes noted on normal circulating blood lymphocytes. However, during culture in T-cell growth factor medium, there was a progressive increase in the percentage of OKT8+ cells, and a concomitant decrease in OKT4+ lymphoblasts. The increase in OKT8+ cells in the MLR-stimulated cultures was paralleled by an increase in specific cell-mediated cytotoxicity against the stimulating lymphocyte population. In addition to the shift in T-lymphocyte subset, there was virtual 100% staining with OKT3 and OKT11a, indicating the T-cell nature of the proliferating cells. OKT10 which was present on a small subset of fresh blood lymphocytes appeared rapidly in stimulated cultures, and was retained on virtually all lymphoblasts of either OKT4+ or OKT8+ subset. OKIa-1 cells increased slowly in PHA-stimulated cultures. HLA-DR+ T cells were detected earlier in MLR cultures. The activation of T lymphocytes results in a significant increase in the number of molecules of OKT11a bound per cell, in concert with the increased avidity of T lymphoblasts for sheep erythrocytes. The significant change in the phenotype and function of lymphoblasts isolated from long-term cultures demonstrates the importance of monitoring cultures, and the potential hazards in equating a cultured cell population with a freshly isolated one.

Specific anti-influenza virus antibody production in vitro by lymphocytes from a subset of patients with hypogammaglobulinemia

Specific anti-influenza virus antibody production in vitro was studied in peripheral blood mononuclear cells from 17 patients with hypogammaglobulinemia. Cells obtained from 6 of 12 patients with common variable hypogammaglobulinemia produced anti-influenza virus antibody, predominantly of the IgM isotype, when cultured in vitro with type A influenza virus. No antibody was produced in vitro, however, by cells from either of two patients with Bruton's type X-linked hypogammaglobulinemia or by cells from any of three patients with X-linked hypogammaglobulinemia and isolated growth hormone deficiency. These studies demonstrate that peripheral blood mononuclear cells from a subset of patients with common variable hypogammaglobulinemia retain the potential to produce specific antibody in response to antigenic stimulation.

Polyclonal activation of immunoglobulin secretion without prior DNA synthesis in human B lymphocytes induced by Klebsiella pneumoniae

The capacity of various cell preparations of Klebsiella pneumoniae K43 (Klebs) to induce [3H]thymidine uptake and immunoglobulin (Ig) secretion by human mononuclear blood cells (MNC) and their lymphocyte subpopulations was investigated. All Klebs preparations were virtually devoid of mitogenic properties, in contrast to control preparations of pokeweed mitogen (PWM) and group A streptococcal cell membranes (A-ScM). Klebs induced differentiation of B cells into Ig-secreting cells. B-cell populations that were sufficiently depleted of T cells to be unresponsive to A-ScM ("highly purified B cells") showed a marked response to Klebs. Similarly, the number of plaque-forming cells (PFC) in Klebs-driven cultures did not change after restitution of T cells, whereas the presence of restituted T cells augmented the B-cell response to PWM and A-ScM. Radical removal of adherent MNC ("monocytes"), however, completely abrogated the PFC response and [3H]thymidine uptake of both MNC activated by Klebs and MNC activated by PWM or A-ScM.

Autologous mixed lymphocyte reaction in health and disease states in man

In this review are discussed the nature of T cell subsets, defined with monoclonal antibodies, responding in T-non-T and T-T autologous mixed-lymphocyte reactions (AMLR) and antigens stimulating in AMLR, soluble products of AMLR and generation of suppressor, helper and cytotoxic functions. On the basis of these data a model of immunoregulation in vivo can be proposed. We believe that AMLR is a real-phenomenon and not an artefact and perhaps represents a mechanism by which various immune functions are regulated, including feedback regulation of AMLR. The significance of AMLR is further supported by studies in various human and animal diseases.

Deficiency of concanavalin A induced suppressor cell activity in patients with primary immunodeficiency disorders

Peripheral blood mononuclear cells (PBMC) from 40 patients with a variety of primary immunodeficiency diseases were examined for concanavalin A (Con A) inducible suppressor activity against proliferative response of autologous and allogeneic PBMC to phytohaemagglutinin (PHA). 45% (12/27) of the patients with common variable immunodeficiency and 86% (6/7) of the patients with selective IgA deficiency demonstrated lack of Con A-induced suppressor activity against proliferative response of autologous/allogeneic PBMC. 2 of 4 patients with X-linked agammaglobulin and both patients, each with Wiskott-Aldrich syndrome and ataxia-telangiectasia, also showed deficient suppressor function. This study demonstrates a deficiency of Con A-inducible suppressor-cell activity in a variety of immunodeficiency diseases. Possible underlying mechanisms for this functional defects are discussed.

Measurement of low levels of immunoglobulins. A simple solid-phase radioimmunoassay

A solid-phase radioimmunoassay for the measurement of immunoglobulins is described, which is simple to perform and possesses sensitivity down to 1 ng/ml. Using anti-light chain serum in the solid-phase, antibody of any class can be measured using suitable labelled antisera.

Heterogeneity of immunological abnormalities in ataxia-telangiectasia

Peripheral blood mononuclear cells from five patients with ataxia-telangiectasia were evaluated for their reactivity with a panel of monoclonal antibodies directed against T-cell subsets and for their in vitro functions in a pokeweed mitogen-induced immunoglobulin biosynthesis assay. All the patients had significantly reduced proportions of cells identified by monoclonal antibodies to subpopulations of T lymphocytes with helper activity (OKT4 and 5/9) and produced low amounts or no IgA and IgG in vitro. Immunoglobulin biosynthesis was increased by the addition of normal x-irradiated peripheral blood mononuclear cells in one of three patients, suggesting a helper T-cell deficiency in this patient and intrinsic B-cell defects in the other two. Two patients had increased proportions of cells identified by a monoclonal antibody to a subpopulation of T lymphocytes which includes suppressor T cells (OKT8), and their cells were able to suppress immunoglobulin biosynthesis by peripheral blood mononuclear cells from normal donors. These findings indicate heterogeneous disturbances of immunoregulatory mechanisms in ataxia-telangiectasia.

Radioimmunoassay of human IgG, IgA and IgM

Radioimmunoassay procedures for the quantitation of nanogram quantities of human immunoglobulin are described. The techniques have been successfully used to measure immunoglobulin secretion in culture supernatants by cultured human lymphocytes. Compared with previously published assays to assess lymphocyte function in vitro these procedures are simple, quick and reliable. A comparison of double-antibody and solid-phase radioimmunoassay is made. Similar sensitivity and variability in IgG and IgA assays were observed but it was not possible to develop a reliable double antibody radioimmunoassay for IgM. The solid-phase assay has several advantages over the double-antibody radioimmunoassays being quick to perform and using standard commercial reagents without necessity for exhaustive absorption.

Disorders of B cells and helper T cells in the pathogenesis of the immunoglobulin deficiency of patients with ataxia telangiectasia

The pathogenesis of the immunoglobulin deficiency of 20 patients with ataxia telangiectasia was studied using an in vitro immunoglobulin biosynthesis system. 10 patients had no detectable IgA in their serum as assessed by radial diffusion in agar and 3 had a reduced serum IgA concentration. The peripheral blood mononuclear cells of 17 of the patients and 17 normal controls were cultured with pokeweed mitogen for 12 d and the immunoglobulin in the supernatants measured. The immunoglobulin synthesis was below the lower limit of the normal 95% confidence interval for IgM in 5 patients, for IgG in 8, and for IgA in 14. The mononuclear cells from 9 of the 10 patients with a serum IgA concentration less than 0.1 mg/ml failed to synthesize IgA in vitro. None of the patients manifested excessive suppressor cell activity. All patients had reduced but measurable helper T cell activity for immunoglobulin synthesis by co-cultured normal pokeweed mitogen-stimulated B cells (geometric mean 22% of normal). Furthermore, the addition of normal irradiated T cells to patient peripheral blood mononuclear cells led to an augmentation of IgM synthesis in 15 of 17 and to increased IgG synthesis in 9 of the 17 patients studied, including 9 of the 12 patients who had synthesized IgG before the addition of the irradiated T cells. In addition, IgA synthesis was increased in all eight patients examined that had serum IgA concentrations greater than 0.1 mg/ml. These studies suggest that a helper T cell defect contributes to the diminished immunoglobulin synthesis. However, a helper T cell defect does not appear to be the sole cause since there was no IgA synthesis by the peripheral blood mononuclear cells of 9 of the 10 patients with a profoundly reduced serum IgA even when co-cultured with normal T cells. Furthermore, the cells of the nine patients with profoundly reduced IgA levels examined also failed to produce IgA when stimulated with the relatively helper T cell-independent polyclonal activators, Nocardia water soluble mitogen or Epstein-Barr virus. Taken together these data support the view that the reduced immunoglobulin synthesis of these patients is due to defects of both B cells and helper T cells. Such a broad defect in lymphocyte maturation taken in conjunction with our demonstration of persistent alpha fetoprotein production by ataxia telangiectasia patients provides support for the proposal that these patients exhibit a generalized defect in tissue differentiation.

Acute lymphoblastic leukemia in children: current status, controversies, and future perspective

Disease-free survival (DFS) in childhood ALL is 60%, and survival in good, average, and poor prognostic groups defined by initial WBC and age is 90, 60, and 45%, respectively. Additional immunological, morphological, biochemical, cytokinetic, and cytogenetic factors have been identified, illustrating the heterogeneity of ALL and its derivation from malignant clones at various stages of differentiation and with varying rates of proliferation. Of biologic importance, these factors may refine further the characteristic features of clinically-determined prognostic groups. Multivariate analysis of large prospective trials with homogeneous therapy will be required to determine the independent prognostic importance of these factors. Current treatment strategies in ALL include (1) tailoring therapy and its intensity to prognostic groups; (2) multiple-drug combinations in induction; (3) early use of intrathecal (IT) methotrexate (MTX); (4) CNS prophylaxis with IT MTX alone in good prognosis patients and combined cranial radiation (CXRT), 1800 rads plus IT MTX, in average and poor prognosis patients. Current studies show a CNS relapse rate of 5% in all prognostic groups. Late neuropsychological defects caused by cranial XRT and IT MTX have prompted programs designed to reduce the potential late toxicity of CNS prophylaxis. More pronounced in younger children, these abnormalities include decreased IQ, visual-motor incoordination, poor performance in mathematics, and memory dysfunction. Until 1980, more intensive induction, consolidation, and maintenance therapy had failed to prolong DFS in children with a poor prognosis. In West Germany (Berlin-Frankfurt-Muenster protocol) a 70 to 75% DFS is seen in all patients regardless of initial WBC, suggesting that effective therapy will override prognostic factors. Ultra-high-dose MTX, without cranial radiation, is also showing promise in poor prognosis patients. Other issues include the optimal duration of therapy, the role of testicular biopsies, and prophylactic testicular radiation. Recent studies suggest that prognostic factors lose their significance after 2 years of continuous complete remission and that 2 years of maintenance therapy is adequate. Bilateral open-wedge testicular biopsies have identified occult testicular disease in 8 to 10% of males. A unified approach to children with leukemia/lymphoma, a group with a particularly poor prognosis, utilizing NHL-type therapy may be more effective than conventional ALL therapy.(ABSTRACT TRUNCATED AT 400 WORDS)

Autologous mixed lymphocyte reaction in man. IV. Decreased autologous mixed lymphocyte culture response in patients with common variable immunodeficiency

The autologous mixed lymphocyte reaction (AMLR) was studied in 18 patients with common variable immunodeficiency. The AMLR was decreased in 10 of 18 (55%) patients with common variable immunodeficiency compared to healthy controls. In allogeneic MLR, T cells from patients were found to be poor responders, and non-T cells poor stimulators, compared to allogeneic MLR between healthy normal controls. In allogeneic MLR, B cells (B cells + null cells) from patients were poor stimulators, whereas macrophages stimulated normally compared to controls. The deficient AMLR could be one of the mechanisms responsible for the increased risk of autoimmune phenomena in a subset of patients with primary immunodeficiency.

Histamine contamination of pokeweed mitogen

The histamine content of commercial preparations of pokeweed mitogen was measured by amino acid analysis technique, automated fluorometry, and bioassay employing the guinea pig ileum. Ten samples from 5 companies were examined and found to contain between 0.026 micrograms and 167.5 micrograms of histamine per ml of solution. The protein content of 9 of these putative 5 mg samples measured by folin assay and by amino acid analysis varied from 0.56 to 4.4 mg. Their amino acid compositions were similar, except for notable variations in 3 of the 16 residues quantitated.

Immunodeficiency diseases: head and neck manifestations

Infections of the upper respiratory tract are common to both the immunodeficient and the normal child during their development. The most common head and neck manifestations of immunodeficiency disease are recurrent suppurative otitis media, tonsillitis, sinusitis, rhinitis, and nasopharyngitis. Often the head and neck specialist is confronted with a child with one or more of these problems and must institute the appropriate therapy or decide on an avenue for further investigation. This paper outlines the major immunodeficiency state, discusses the immune defects thought to be responsible for the spectrum of clinical findings, and suggests a systematic approach to the evaluation of these difficult diseases. The recognition of immunodeficient individuals is an important step in their treatment so that adjunctive immunological therapy can be provided.

Effect of indomethacin on phytohemagglutinin-stimulated peripheral blood lymphocytes in thyroid autoimmune diseases

Suppressor lymphocyte function was evaluated in control subjects and in patients with autoimmune thyroid disease, utilizing an assay in which indomethacin was added to lymphocyte cultures to inhibit prostaglandin-producing suppressor cells. This assay is based on the observation that the addition of indomethacin, a potent prostaglandin synthesis inhibitor, to phytohemagglutinin-stimulated peripheral blood lymphocytes should cause an increase in the incorporation of iododeoxyuridine in control subjects and a smaller increase in diseases with reduced prostaglandin-producing suppressor cells. The addition of indomethacin, 1 microgram/ml, stimulated iododeoxyuridine incorporation in phytohemagglutinin-stimulated cultures in control subjects to an index value of 1.43 (i.e., the increment in iododeoxyuridine incorporation with both indomethacin and phytohemagglutinin was 43% greater than the incorporation with phytohemagglutinin alone). The stimulation index was significantly lower in patients with Graves' disease who were toxic and untreated (1.18 +/- 0.25, mean +/- SD; P less than 0.003). Patients who were toxic while receiving antithyroid drugs or after radioiodine therapy or patients euthyroid after treatment had a mean stimulation index in the normal range, although the spread of data was very large in these groups. Responses in patients with Hashimoto's thyroiditis were also quite variable. The average response was 1.74 +/- 0.72, with 40% of the patients showing a high stimulation index. This study supports our previous investigations in which we used different assay systems for measuring suppressor-cell function in patients with thyroid autoimmune diseases and indicates that a defect in suppressor lymphocyte function is measureable by another technique. The abnormality persists in some cases after metabolic control has been achieved, but usually returns toward normal over months or years.