Immunoregulatory Function of T8 and T4 Cells from Synovial Fluid and Blood of Patients with Rheumatoid Arthritis or Other Forms of Chronic Arthritis

The suppressor effect of synovial fluid (SF) T8 cells and blood T8 cells on the pokeweed mitogen (PWM)-induced T4 cell-dependent immunoglobulin production of autologous blood B cells was studied in nine patients with chronic rheumatic diseases (six patients with rheumatoid arthritis (RA), one patient with juvenile RA, and two patients with other forms of chronic arthritis). The suppressor effect of SF T8 cells was of the same magnitude as that of equal numbers of blood T8 cells from patients and healthy controls. However, the relative number of T8 cells was higher among SF T cells than among blood T cells in several cases. Good synovial T8 cell suppression was also demonstrated in coculture experiments where SF T4 cells and B cells were used. In PPD (purified protein derivative of tuberculin)-stimulated cultures the suppressor effect of SF T8 cells as well as of blood T8 cells from patients and controls was lower than it was in PWM-stimulated cultures. In most patients SF T4 cells showed a much better PWM-induced helper function than did non-fractionated SF T cells. Thus the poor PWM induced helper effect of non fractionated synovial T cells was in some cases mainly due to the suppressor effect of T8 cells, whereas in some cases there was also a deficient helper function of synovial T4 cells.     

Human B cell function in responder and non-responder individuals. II. The role of T helper cells in promoting the PWM-induced B cell production of immunoprotein

Sorted OKT4+ cells treated with pokeweed mitogen (PWM) and subsequently X-irradiated were used as a source of helper T cells to examine human T and B cell function. PWM-induced immunoprotein synthesis by human peripheral blood lymphocytes was the model used to study the cellular interactions. PWM was shown to induce helper T cell function which caused non-PWM treated B cells to secrete immunoglobulin. PBL from certain individuals could not be induced by PWM to secrete Ig therefore allogeneic co-cultures of helper T cells and B cells were examined to define the defective cell population. Ig synthesis in allogeneic cultures of T and B cells was always greater than that observed in autologous cultures when cells from responders were assayed. However, when allogeneic cultures were initiated using B cells from a responder and PWM treated T cells from a non-responder and examined for Ig synthesis, the B cell responses were markedly lower than seen in the autologous responder cultures. In addition, PWM activated helper T cells from a responder induced a significantly higher Ig synthesis by B cells from a non-responder. These observations indicate that PBL from individuals who do not respond in a PWM driven Ig synthesis assay have relatively normal B cell function but are deficient in helper T cell function.     

B lymphocyte function in patients with rheumatoid arthritis: impact of regulatory T lymphocytes and macrophages--modulation by antirheumatic drugs

The present work analyses B lymphocyte functions in vitro in patients with rheumatoid arthritis (RA). The impact of gold salts and penicillamine on human B lymphocyte function in vitro is discussed. Synovial fluid monocytes/macrophages increased both the polyclonally induced and the antigen-induced blood lymphocyte proliferation and increased the numbers of immunoglobulin-secreting blood B lymphocytes generated by pokeweed mitogen (PWM), a T cell-dependent polyclonal activator. The lymphostimulatory factor(s) interleukin-1, which can be produced by monocytes/macrophages, was found in most cell-free synovial fluid specimens, but only in a few paired serum samples. Thus, in vivo activated synovial monocytes/macrophages may modulate lymphocyte functions. Compared to blood, synovial fluid T lymphocytes comprised fewer T4+ (helper/inducer) cells and more T8+ (suppressor/cytotoxic) cells. Synovial fluid lymphocytes proliferated poorly when stimulated polyclonally. However, the proliferative responses to microbial antigens as well as the lectin-induced lymphokine production equaled those of blood lymphocytes. In about half of RA patients, T4+ cells from synovial fluid increased the PWM-induced immunoglobulin secretion by autologous blood B lymphocytes to higher levels as compared to similar experiments with blood T4+ cells. Synovial fluid T8+ cells suppressed PWM-induced immunoglobulin production of autologous mononuclear cells to the same degree as seen with blood T8+ cells. A large proportion of synovial fluid T subsets expressed Ia antigens, probably due to in vivo activation. Thus, synovial T helper/inducer and T suppressor/cytotoxic cells may modulate the functional activities of synovial B lymphocytes. Among mononuclear cells isolated from synovial fluid and synovial tissue, considerable numbers of B lymphocytes spontaneously secreting IgG were found; fewer B cells secreted IgM and IgA. Rheumatoid factor activity was noted in about 7% of the IgG-producing cells. Synovial fluid mononuclear cells did not produce immunoglobulins in cultures stimulated with PWM, unless synovial T cells were removed and replaced with autologous blood T cells. Under these conditions synovial fluid B lymphocytes were induced by PWM to considerable IgG synthesis; fewer cells secreted IgM and IgA. About 8-9% of the induced IgM- and IgG-synthesizing cells displayed rheumatoid factor activity. Aurothiomalate markedly inhibited PWM-induced immunoglobulin production by normal lymphocytes cultured in vitro, probably by affecting monocyte/macrophage-lymphocyte interactions. The drug also had a direct inhibitory action on B lymphocytes, whereas T cells were resistant.(ABSTRACT TRUNCATED AT 400 WORDS)     

Demonstration of a Helper Factor(s) with T-Cell-Replacing Activity in Synovial Fluid

Cell-free synovial fluid (SF) obtained from patients with rheumatoid arthritis contains a helper factor(s) capable of augmenting the generation of plaque-forming cells (PFC) in pokeweed mitogen (PWM)-stimulated normal peripheral blood mononuclear cells (PBMC). This helper factor behaves like a polyclonal B-cell activator, in that it triggers the formation of IgM, IgG, and IgA PFC. However, SF has little or no effect on the proliferation of PWM-activated PBMC. Furthermore, SF was capable of replacing T cells for PWM-induced differentiation but not proliferation of enriched human blood B lymphocytes. No helper factor or T-cell-replacing activity was found in SF from patients with traumatic synovitis. Fractionation of SF containing helper activity on staphylococcal protein A column indicated that the activity is induced by biologically active molecules distinct from materials that preferentially bind to protein A such as IgG immune complexes. We conclude that the present activity has striking similarities to the recently described B-cell differentiation factor that is produced by specifically activated T-cell lines in vitro.     

T-Cell Immunoregulatory Functions in Rheumatoid Arthritis Patients

We have studied the immunoregulatory function of T8+ (suppressor/cytotoxic) and Leu3a+ (inducer/helper) T cells from rheumatoid arthritis (RA) patients by measuring the effect of these T-cell subpopulations on the generation of immunoglobulin-secreting cells by normal allogeneic B cells after stimulation with pokeweed mitogen (PWM) in vitro. When T8+ or Leu3a+ cells from blood or synovial tissue from nine patients were substituted for T8+ or Leu3a+ cells, respectively, from normal blood mononuclear cells (MNC), RA T8+ cells showed an increased suppressor activity, whereas RA Leu3a+ cells were, except for one patient, weak augmentors. Unreplaced normal MNC and MNC replaced with allogeneic normal T-cell subpopulations responded equally to PWM. When T8+ plus Leu3a+ cells from the same patient replaced normal T cells, high B-cell responses were detected. Normal T8+ plus Leu3a+ cells generally supported the response to a lower degree. Substitution with two allogeneic T-cell subpopulations did not result in a B-cell response to PWM. Thus, whereas RA T8+ seemed to be strong suppressors and RA Leu3a+ cells weak augmentors by themselves, together they are possibly able to generate a B-cell stimulatory potential that might be of pathogenetic significance in the patients.     

High Incidence of Spontaneous Ig-Producing Lymphocytes in Peripheral Blood and Synovial Fluid of Patients with Active Seropositive Rheumatoid Arthritis

Numbers of in vitro spontaneous IgG, IgM and IgA plaque-forming cells (PFC) as assessed by a modification of the protein A haemolytic plaque assay were determined in the blood and synovial fluid of patients with seropositive rheumatoid arthritis (RA) and compared with those of control groups. The total numbers of PFC were significantly higher in the peripheral blood of patients with active seropositive RA than in that of normal controls. In addition, most B lymphocytes in the synovial fluid of patients with active seropositive RA were active immunoglobulin (Ig) producers, whereas synovial fluid lymphocytes from patients with inactive seropositive RA and seronegative arthritis were not. In general, IgA PFC were relatively high in blood, whereas IgG PFC dominated in the synovial fluid. IgM PFC appear to be relatively low in blood and synovial fluid. However, a relative increase of IgG PFC was noted in the peripheral blood of patients with active RA. To test for polyclonality of the increased Ig synthesis, we tested the sera of patients and controls for the presence of polyclonal antibodies against sheep erythrocytes (SRBC) and SRBC modified by fluorescein isothiocyanate (FITC) and trinitrophenyl (TNP). No differences were observed with SRBC and TNP-SRBC agglutinin titres between patients and controls, but patients with RA had higher titres of FITC-SRBC agglutinins than normal sera. This finding supports the concept of a polyclonal nature of antibody production in RA patients.     

Defective in vitro immunoglobulin production in response to pokeweed mitogen in patients with Hodgkin's disease pretreatment and in remission

In vitro production of IgG and IgM from peripheral blood lymphocytes and B-cell enriched fractions was assessed in a group of Hodgkin's disease (HD) patients and normal controls using pokeweed mitogen (PWM) stimulation. Our studies demonstrated a significant (P less than 0.01) reduction in the absolute number of helper (OKT4 positive) T cells and a significant alteration in the helper/suppressor T-cell ratio (0.89 +/- 0.15) compared to normal (1.83 +/- 0.31). Results from PWM stimulation experiments demonstrated that HD patients produced significantly lower IgG (P less than 0.01) and IgM (P less than 0.01) levels than controls. Synthesis of IgM but not IgG induced by PWM was subnormal after addition to patient B-cell cultures of autologous irradiated T cells or allogeneic irradiated normal T lymphocytes. Irradiated T cells from HD patients were as effective as normal T cells in helping PWM induced IgG and IgM synthesis by normal B cells. Our results suggest that in HD impaired circulating B-cell function is partly due to T-suppressor cell activity and furthermore that B-cell subpopulations producing different immunoglobulin isotypes may either be defective or vary in their susceptibility to T-cell suppression.     

In vitro immunoglobulin production by mononuclear cells in rheumatoid arthritis

Since patients with rheumatoid arthritis (RA) exhibit serum hypergammaglobulinemia and autoantibody (rheumatoid factor) production, we compared elaboration and control of in vitro RA mononuclear cell (MNC), Ig assayed by enzyme-linked immunoassays or by hemolytic plaque formation, in 37 RA patients and 17 normal subjects. We found (1) RA spontaneous plaque-forming cells were significantly reduced (RA 344 vs normal 627 PFC/10(6) MNC, P less than 0.002); (2) RA spontaneous IgG and IgM (but not IgA) elaboration was significantly diminished (IgG RA 339, normal 776; IgM RA 255, normal 869 ng/ml, P less than 0.001; IgA RA 87, normal 124); (3) RA stimulated IgG and IgM production (but not IgA) was also decreased (IgG RA 2434, normal 3862, P less than 0.06; IgM RA, 1676, normal 3323, P less than 0.005; IgA RA 1859, normal 2315); (4) reduced RA Ig elaboration was not clearly due to altered numbers of T or non-T cells, age, medications, clinical features of disease, or response kinetics; (5) relative improvement of RA in vitro IgG, but not usually IgM, secretion followed removal of adherent cells, addition of indomethacin or addition of mitomycin C-treated T cells; (6) MNC from synovial fluids, but not bone marrows, exhibited spontaneous Ig production in excess of stimulated synovial fluid cellular or peripheral blood Ig elaboration. These observations indicate selective impairment of peripheral blood MNC IgG and, particularly, IgM secretion in RA. This defect appears to reflect accessory cell influences which differ from normal as well as the sequestration of primed or activated cells in the synovial fluid.     

Autologous Mixed Lymphocyte Reactions in Patients with Rheumatoid Arthritis and Juvenile Rheumatoid Arthritis: Both Non-T Cells and in-Vivo-Activated T Cells Can Act as Stimulator Cells

The lymphocyte responses in autologous mixed lymphocyte reactions (AMLR) between irradiated non-T and T lymphocytes from the peripheral blood (PB) of rheumatoid arthritis (RA) and juvenile RA (JRA) patients were decreased compared with the AMLR responses of normal PB lymphocytes. Normal AMLR responses were seen in the synovial tissue and the synovial fluid lymphocytes from RA and JRA patients. The lymphocyte responses were also decreased in AMLR between irradiated non-T cells from peripheral blood and T cells from synovial tissue (ST) in RA patients and between irradiated non-T from PB and synovial fluid (SF) T cells in JRA patients. However, when irradiated non-T cells from ST of RA patients or from SF of JRA patients were mixed with autologous PB T lymphocytes, increased lymphocyte responses were observed. SF T lymphocyters and ST T cells were also shown to stimulate autologous PB T lymphocytes.     

T lymphocytes of the human colonic mucosa: functional and phenotypic analysis.

Normal human colonic lymphocyte populations were isolated for both phenotypic analysis by double-label immunofluorescence and assessment for regulatory effects on Ig production by co-culture with responder cells from colonic mucosa and peripheral blood. Mean CD4:CD8 ratios for colonic intraepithelial lymphocytes (IEL) and lamina propria lymphocytes (LPL) were comparable to values obtained from tissue sections. IEL alone did not produce Ig in vitro and were without effect on Ig production when co-cultured with LPL. However, T-enriched LPL had a marked helper effect for T-depleted LPL. Maximal help was for IgA production, increasing with numbers of T-enriched cells. In colonic LPL T-depleted and T-enriched co-cultures, pokeweed mitogen (PWM) had no significant effect. By contrast, in co-cultures of T-enriched and T-depleted peripheral blood mononuclear cells, Ig production was PWM-dependent. In all experiments with colonic mucosal responder cells, IgG production was low. The effects of unfractionated colonic biopsy lymphocytes on T-depleted peripheral blood mononuclear cells were additive for IgM production and synergistic for IgA synthesis, although almost no IgG was produced. Moreover, PWM had helper effects for IgM, but was suppressive for IgA production. These data suggest that colonic mucosal regulatory cells reside in the lamina propria, and predominantly provide help for IgA and IgM synthesis. The data further suggest the existence of a pre-stimulated IgA-specific T helper cell population.     

Enhanced T helper cell function for the spontaneous production of IgM rheumatoid factor in vitro in rheumatoid arthritis.

Co-culture experiments between T and B cells from normal subjects and rheumatoid arthritis (RA) patients were performed in order to assess the immunoregulatory effects of T cells on spontaneous production of IgM rheumatoid factor (IgM-RF). Cultures of normal B cells with normal, autologous or allogeneic T cells failed to synthesize IgM-RF. In contrast, RAT cells promoted IgM-RF production from normal B cells as well as from RA B cells. The 'helper' effect of T cells from RA patients for IgM-RF production was not HLA-DR4 restricted and could not be accounted for by an allogeneic effect. These observations suggest that activated T helper cells may contribute to the production of IgM-RF in RA.     

Decreased suppressor T cell activity in patients with hepatic cirrhosis (HC).

Hypergammaglobulinaemia (HGG) is frequently found in patients with hepatic cirrhosis (HC). Using an assay system of in vitro PWM-stimulated immunoglobulin (Ig) production, the amounts of IgG, IgA, and IgM produced by peripheral blood lymphocytes (PBL) from 15 HBs Ag-negative patients with HC and from 16 age-matched healthy subjects were quantitated by radioimmunoassay. We found that PBL from patients with HC produced significantly greater amounts of IgG (P less than 0.05) but not IgA or IgM than did those from control subjects. This increased IgG production by PBL from patients with HC was attributed to enhanced T helper activity and not to enhanced B cell function. We also searched for defects in naturally occurring suppressor T cell activity which is sensitive to irradiation. Irradiation-induced enhancement for IgG production was significantly lower in patients with HC compared with age-matched control subjects (P less than 0.01). Similarly, we examined the effect of Con A-induced suppressor T cells on the in vitro PWM-stimulated IgG production by allogeneic PBL and observed the decrease of Con A-induced suppressor T cell activity in patients with HC (P = 0.01). We conclude, therefore, that the increased serum levels of Ig, particularly IgG in patients with HC may result from in part on the basis of depressed ability of naturally occurring suppressor T cells or Con A-induced suppressor T cells to suppress Ig production.     

Immunoglobulin G and A Antibody Responses to Bacteroides forsythus and Prevotella intermedia in Sera and Synovial Fluids of Arthritis Patients

The objective of the present study was to investigate immunoglobulin G (IgG) and IgA antibody immune responses to Porphyromonas gingivalis, Prevotella intermedia, Bacteroides forsythus, and Candida albicans in the sera of patients with rheumatoid arthritis (RA), the synovial fluid (SF) of patients with RA (RA-SF samples), and the SF of patients without RA (non-RA-SF samples). An enzyme-linked immunosorbent assay was used to determine IgG and IgA antibody levels in 116 serum samples from patients with RA, 52 RA-SF samples, and 43 non-RA-SF samples; and these were compared with those in SF samples from 9 patients with osteoarthritis (OA-SF samples) and the blood from 100 donors (the control [CTR] group). Higher levels of IgG antibodies against B. forsythus (P < 0.0001) and P. intermedia (P < 0.0001) were found in non-RA-SF samples than in OA-SF samples, and higher levels of IgG antibodies against B. forsythus (P = 0.003) and P. intermedia (P = 0.024) were found in RA-SF samples than in OA-SF samples. Significantly higher levels of IgA antibodies against B. forsythus were demonstrated in both RA-SF and non-RA-SF samples than in OA-SF samples. When corrected for total Ig levels, levels of IgG antibody against B. forsythus were elevated in RA-SF and non-RA-SF samples compared to those in OA-SF samples. Lower levels of Ig antibodies against B. forsythus were found in the sera of patients with RA than in the plasma of the CTR group for both IgG (P = 0.003) and IgA (P < 0.0001). When corrected for total Ig levels, the levels of IgG and IgA antibodies against B. forsythus were still found to be lower in the sera from patients with RA than in the plasma of the CTR group (P < 0.0001). The levels of antibodies against P. gingivalis and C. albicans in the sera and SF of RA and non-RA patients were comparable to those found in the respective controls. The levels of IgG and IgA antibodies against B. forsythus were elevated in SF from patients with RA and non-RA-SF samples compared to those in OA-SF samples. Significantly lower levels of IgG and IgA antibodies against B. forsythus were found in the sera of patients with RA than in the plasma of the CTR group. This indicates the presence of an active antibody response in synovial tissue and illustrates a potential connection between periodontal and joint diseases.     

Immunoglobulin G and A antibody responses to Bacteroides forsythus and Prevotella intermedia in sera and synovial fluids of arthritis patients

The objective of the present study was to investigate immunoglobulin G (IgG) and IgA antibody immune responses to Porphyromonas gingivalis, Prevotella intermedia, Bacteroides forsythus, and Candida albicans in the sera of patients with rheumatoid arthritis (RA), the synovial fluid (SF) of patients with RA (RA-SF samples), and the SF of patients without RA (non-RA-SF samples). An enzyme-linked immunosorbent assay was used to determine IgG and IgA antibody levels in 116 serum samples from patients with RA, 52 RA-SF samples, and 43 non-RA-SF samples; and these were compared with those in SF samples from 9 patients with osteoarthritis (OA-SF samples) and the blood from 100 donors (the control [CTR] group). Higher levels of IgG antibodies against B. forsythus (P < 0.0001) and P. intermedia (P < 0.0001) were found in non-RA-SF samples than in OA-SF samples, and higher levels of IgG antibodies against B. forsythus (P = 0.003) and P. intermedia (P = 0.024) were found in RA-SF samples than in OA-SF samples. Significantly higher levels of IgA antibodies against B. forsythus were demonstrated in both RA-SF and non-RA-SF samples than in OA-SF samples. When corrected for total Ig levels, levels of IgG antibody against B. forsythus were elevated in RA-SF and non-RA-SF samples compared to those in OA-SF samples. Lower levels of Ig antibodies against B. forsythus were found in the sera of patients with RA than in the plasma of the CTR group for both IgG (P = 0.003) and IgA (P < 0.0001). When corrected for total Ig levels, the levels of IgG and IgA antibodies against B. forsythus were still found to be lower in the sera from patients with RA than in the plasma of the CTR group (P < 0.0001). The levels of antibodies against P. gingivalis and C. albicans in the sera and SF of RA and non-RA patients were comparable to those found in the respective controls. The levels of IgG and IgA antibodies against B. forsythus were elevated in SF from patients with RA and non-RA-SF samples compared to those in OA-SF samples. Significantly lower levels of IgG and IgA antibodies against B. forsythus were found in the sera of patients with RA than in the plasma of the CTR group. This indicates the presence of an active antibody response in synovial tissue and illustrates a potential connection between periodontal and joint diseases.     

The production of a soluble human T-lymphocyte derived factor which substitutes for helper T lymphocytes in the in vitro production of immunoglobulin.

A soluble factor(s), human T-lymphocyte derived help factor (HHF), generated following pokeweed mitogen (PWM) activation of irradiated human peripheral blood T lymphocytes was shown to substitute partially for T-lymphocyte helper activity in the T-lymphocyte dependent PWM-stimulated synthesis of immunoglobulin by B cells. The degree of help provided was proportional to the number of cultured irradiated T-lymphocytes producing factor as well as the amount of factor added to the B-cell culture. The helper effect was equally provided by HHF syngeneic and allogeneic to the B lymphocyte. Although there was little stimulation of total protein synthesis, the synthesis and secretion of IgG, IgM and IgA were all stimulated three- to ten-fold by this factor. The B cells required a minimum of 40--55 h exposure to the factor from the initiation of the culture for an increase in Ig synthesis on day 5 to be observed. Addition of HHF to B cells pre-incubated with PWM for different time intervals showed that a maximum helper effect was exerted when the factor was added on day 0. Addition on day 1 provided less than 20% of maximum help. The factor did not promote significant increases in either B-cell or T-cell cell division.     

Evidence for a malignant proliferation of IgE-class specific helper T cells in a patient with Sézary syndrome exhibiting massive hyperimmunoglobulinemia E

Peripheral blood mononuclear cells (PBM) from a patient with Sézary syndrome exhibiting massive hyperimmunoglobulinemia E were examined in vitro. The patient's PBM and B cells (Bp) but not normal individuals' PBM and B cells (Bn) produced spontaneously large amounts of IgE. The addition of pokeweed mitogen (PWM) did not affect IgE production by both the patient's and normal individuals' PBM. The IgE production by PWM-stimulated Bp was depressed when cocultured with normal T cells but not depressed with the patient's T cells (Tp). When Tp were cocultured with Bn, significantly larger than expected quantities of IgE were produced. Ig assay of the same supernates showed that Tp had significantly less helper activities for IgG, IgA, and IgM production. Almost all Tp possessed the Leu3a and Leu3b antigens which are expressed on the helper/inducer T cell subset. These results indicate that the neoplastic cells in this patient originated from a subset of T cells programmed not for IgG, IgA, and IgM, but for IgE synthesis.     

Selective enhancement of human IgE production in vitro by synergy of pokeweed mitogen and mercuric chloride

IgE production in vitro was investigated in cultures of human peripheral blood mononuclear cells (MNC) from non-atopic donors with pokeweed mitogen (PWM), mercuric chloride (HgCl2), or both. PWM alone induced a few IgE immunoglobulin secreting cells (ISC) detected by reverse plaque forming cells (PFC) and many IgG, IgM, and IgA PFC. HgCl2 alone failed to produce significant numbers of ISC of any class. PWM plus HgCl2 caused a selective increase of IgE PFC without affecting IgG, IgM, and IgA PFC. Co-cultures of B cells plus mitomycin C (MMC) treated T cells stimulated by PWM alone produced more IgG, IgM, IgA and IgE PFC than those of B cells plus T cells. However, PWM plus HgCl2 produced significantly more IgE PFC selectively in those cultures. This effect was observed in the cells of most of the donors, but a few donors showed different responses.     

T8 cell suppression of antigen- and mitogen-induced T4 cell dependent immunoglobulin production.

The suppressor effect of T8 cells on antigen-induced, as compared to pokeweed mitogen-induced, T4 cell dependent immunoglobulin (Ig) production by B cells of healthy subjects was studied. The antigens used were purified protein derivative of tuberculin (PPD) and tetanus toxoid (TT). The suppressor effect of T8 cells on IgG, IgM and IgA responses in co-cultures of T4 cells and B cells was significantly stronger in the pokeweed mitogen driven system than in PPD- and TT-driven cultures under the same experimental conditions.     

Aberrant T-regulation in rheumatoid arthritis and IgA nephropathy affects CD5+ and CD5- B lymphocytes equally.

T-suppressor function and T-helper function in healthy adults, elderly patients with non-immune diseases, and patients with rheumatoid arthritis (RA) and IgA nephropathy (IgAN) were titrated by adding graded concentrations of CD8+ cells to autologous CD8-depleted peripheral blood mononuclear cells (PBMC), or CD4+ cells to CD8- 4- PBMC, respectively. Following culture with pokeweed mitogen (PWM), numbers of CD5+ and CD5- immunoglobulin-secreting cells were determined using a combination of rosetting with anti-CD5-coated Dynabeads and reverse haemolytic plaque formation (Jones, 1990). Of 11 RA patients studied, eight had slightly reduced suppressor activity for CD5+ and CD5- IgM-secreting cells, and three with active disease and high serum levels of C-reactive protein, could not suppress IgG, IgA or IgM secretion by either B subset. Helper activity for both CD5+ and CD5- B cells was slightly but significantly increased in RA patients. One of eight patients with IgAN could not suppress IgG, IgA or IgM production by CD5+ or CD5- B cells, and all IgAN patients required strikingly fewer CD4+ cells for PWM-induced activation of CD5+ and CD5- B cells than controls. It was concluded that in two immunologically mediated diseases in which some patients have raised numbers of circulating CD5+ B cells, aberrant T-regulation affects CD5+ and conventional CD5- B cells equally.     

Bone marrow transplantation in man. Analysis of T and B cell functions in PWM driven Ig production.

The functional activity of B and T lymphocytes from the blood of eight patients, who had successfully been treated with allogeneic bone marrow for severe aplastic anaemia or acute leukaemia, was studied in pokeweed mitogen (PWM) driven polyclonal immunoglobulin synthesis. Activity of B cells was measured as IgM and IgG synthesis by a standard number (40 X 10(3] of patient lymphocytes in the presence or absence of healthy donor T cells. In addition, the frequency of PWM reactive B cells, giving rise to IgM and/or IgG producing daughter cells, was estimated by limiting dilution analysis. With this method, it was found that only a small percentage (1-3%) of peripheral blood B cells from healthy individuals is reactive to PWM. In the patients, both parameters for B cell reactivity were decreased during the first 40 weeks after bone marrow transplantation. As parameters for T cell activity, help and suppression on the Ig production by healthy donor lymphocytes were tested. In most patients, T helper cell activity was strongly decreased, whereas some patients had excessive T suppressor cell activity. The observed functional activities were only partially correlated with the marker profile of the T cell populations, as detected by reactivity with monoclonal antibodies. Each patient had a distinct, individual pattern of reconstitution of these functions. There was no positive correlation between Ig production in vitro and the capacity to form antibodies in vivo, nor between the other in vitro findings and clinical features, such as the occurrence of infections or graft versus host disease.