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Biomedical subjects

S Izui

Publications and source records attributed to S Izui.

At least 127 records · Page 7Linked to original sources
PubMed1989

Rheumatoid factor autoantibody-binding site: a molecular analysis using monoclonal antibodies with dual anti-TNP and anti-IgG activities.

Two out of five murine IgG3 anti-trinitrophenyl (TNP) monoclonal antibodies (mAb) obtained either by immunization with TNP-keyhole limpet hemocyanin (KLH) (CB1, CB5, CB6 and 4H10) or with dinitrophenyl-lipopolysaccharide (9A6), exhibited anti-IgG rheumatoid factor (RF) activity (CB6 and 4H10). The anti-IgG activity of these two anti-TNP RF was specifically inhibited by murine IgG as well as by the hapten TNP. In order to identify the structural basis for the anti-IgG activity, the nucleotide sequences encoding the VH and VL regions were determined. By comparing the V regions of the non-RF and RF anti-TNP mAb, it was found that one anti-TNP RF antibody, CB6, shares virtually identical VL and VH regions with two anti-TNP antibodies, CB1 and CB5, but markedly differs from these in the D region. Furthermore, the light chain framework region 2 (FR2) and FR3 of non-RF mAb, CB1, CB5 and 9A6, have amino acid sequences almost identical to those claimed for anti-IgG1 RF activity (Shlomchik et al., J. Exp. Med. 1986. 164: 407). Our findings suggest, at least in the case of CB6 mAb, the involvement of CDR, but not light chain FR residues, in IgG binding.

Amino Acid Sequence↗
PubMed1989

Differential effect of the autoimmune Yaa and lpr genes on the acceleration of lupus-like syndrome in MRL/MpJ mice.

The Yaa gene (Y chromosome-linked autoimmune acceleration), linked to the BXSB/MpJ Y chromosome, and the autosomal recessive lpr (lymphoproliferation) gene have been shown to accelerate the progression of the lupus-like autoimmune syndrome in the BXSB and MRL strains, respectively. To compare more directly the role of the Yaa and lpr genes in the development of the autoimmune syndrome, the Y chromosome of BXSB mice was transferred to MRL mice by backcross procedures, and the effect of the Yaa gene on the autoantibody formation and the development of lupus-like nephritis in MRL mice was investigated in comparison with those bearing the lpr mutation. The Yaa gene as well as the lpr gene were able to shorten the life span of MRL mice as a result of the accelerated development of lethal lupus-like nephritis. However, the acceleration promoted by the Yaa gene (50% mortality rate: 12 months) was less severe than that induced by the lpr gene (50% mortality rate: 7 months). This may be related to the finding that the lpr gene enhanced the production of a large spectrum of autoantibodies, including anti-DNA, rheumatoid factors and anti-gp70, and of cryoglobulins, whereas only anti-gp70 production among the autoantibodies studies was markedly enhanced by the Yaa gene. The selective autoimmune accelerating effect of the Yaa gene was similarly observed in (NZW X MRL)F1 hybrid mice. Our results suggest that the Yaa gene, unlike the lpr gene, exhibits selective autoimmune accelerating activity, but as a result of increased formation of certain nephritogenic autoantibodies such as anti-gp70 antibodies, the Yaa gene is able to accelerate the progression of lupus-like nephritis in lupus-prone mice.

Animals↗
PubMed1989

Autoantibody repertoire analysis in normal and lupus-prone mice.

We have analyzed at the clonal level (limiting dilution assay) the repertoire of lipopolysaccharide (LPS)-responsive murine B cells committed to the production of autoantibodies characteristic of systemic lupus erythematous (SLE), i.e. anti-single-stranded DNA (ssDNA), anti-double-stranded DNA, anti-Sm and rheumatoid factors (RF). Our results demonstrated that: (1) the frequency of precursor B cells producing each lupus autoantibody (approximately 1 in every 100-400 LPS-responding B cell) was similar in two non-autoimmune (C57BL/6 and BALB/c) and four SLE-prone (NZB, (NZB x NZW)F1, MRL/MpJ and BXSB/MpJ) mice despite the marked differences in autoimmune responses in the different SLE-prone mice, and (2) the relative frequency of autoantibody-secreting precursor B cells was constant throughout life, and equally distributed among activated and resting B-cell populations and among B cells from the peritoneal cavity and spleen. The lack of association of anti-ssDNA secretion with anti-Sm or RF secretion in cultures set up with a smaller number of B cells ruled out the possibility that the similar frequency of different autoantibody-secreting cell precursors is due to the poly-specificity of IgM autoantibodies. Notably, the frequencies of autoantibody-secreting precursor cells were significantly lower, approximately 4 and 10 times, than those of anti-tetanus toxoid and anti-dinitrophenyl antibody-producing precursor B cells, respectively. The similar frequency of precursor B cells producing four different lupus autoantibodies on the one hand and the considerable variation in each autoimmune response among SLE-prone mice on the other, support the hypothesis that specific stimulatory mechanisms may govern each autoimmune response in different SLE strains of mice.

Animals↗
PubMed1989

Long-term observations of autoimmune-prone mice treated for autoimmune disease by allogeneic bone marrow transplantation.

Long-term effects of allogeneic bone marrow transplantation (ABMT) across major histocompatibility complex barriers were studied in (NZB x NZW)F1 (B/W), BXSB, and MRL/Mr-lpr-lpr (MRL/lpr) mice with established autoimmune disease at the time of ABMT. In the BXSB or B/W mice, ABMT cured all aspects of autoimmune disease. Glomerular damage, revealed by histological study was dramatically improved. Serological abnormalities and immunologic functions also were normalized. Correction of autoimmune disease and advanced renal disease in BXSB and B/W mice regularly lasted greater than 5-6 mo and even 1 yr after ABMT. In the MRL/lpr mice, however, autoimmune and renal disease at first improved but then recurred after ABMT, apparently because of intolerance of mice for high doses of irradiation and a high degree of resistance of recipient stem cells to irradiation. In this model, H-2 typing revealed that by the time of relapse, immunocompetent cells of the chimeric mice had been replaced by host (MRL/lpr; H-2k) cells. B220+ Ly-1+ cells, present in increased numbers in untreated MRL/lpr mice, initially returned to normal levels after ABMT but then reappeared in the MRL/lpr mice that had received marrow from donors having few such lymphocytes. Thus, our results show that MRL/lpr mice possess abnormal radioresistant stem cells and provide impressive evidence that the origin of autoimmune diseases in this strain, as in the several other strains studied, residues in abnormalities present in stem cells.

Animals↗
PubMed1989

Presence of a very small population of Thy-1+, L3T4+ cells producing large amounts of IL-3 in young athymic nude mice.

A mixture of phorbol myristate acetate (PMA) and ionomycin was found to stimulate spleen and lymph node cells (LNC) from 6 to 8 week-old-athymic BALB/c nude mice, as well as from control +/+ mice, to secrete interleukin-3 (IL-3) in vitro. The specificity of the IL-3 bioassay was attested to by the use of rabbit anti-IL-3 antibodies, and by the detection of an accumulation of IL-3 mRNA. Cytotoxic treatment with relevant antibodies showed that the cells responsible for the IL-3 production in athymic nude mice was Thy-1+, L3T4+, Ly2-, while both L3T4+ and Ly 2+ cells produced IL-3 in control +/+ mice. Although the levels of IL-3 secreted by nude LNC varied among experiments, nude LNC were able to produce IL-3 at a level comparable to or higher than +/+ LNC. In addition, nude LNC consistently secreted two to three times more granulocyte-macrophage colony-stimulating factor (GM-CSF) than +/+ LNC, and the majority of GM-CSF secretion was dependent on the presence of L3T4+ cells. In contrast, IL-2 production by nude LNC was markedly limited. Since the flow microfluorometry analysis failed to demonstrate the presence of L3T4+ cells (less than 1%) in nude LNC, compared with 40-50% L3T4+ cells in +/+ LNC, our results suggest that athymic nude mice have a small population of Thy-1+, L3T4+ cells characterized by its ability to secrete IL-3 and GM-CSF at a very high rate.

Animals↗
PubMed1989

Recombinant interleukin-2 therapy of systemic lupus erythematosus in the New Zealand black/New Zealand white mouse.

New Zealand Black/New Zealand White (NZB/W) mice, a model of systemic lupus erythematosus (SLE), have age-dependent loss of interleukin-2 (IL-2) production. To determine if replacement therapy would influence the course of autoimmune disease, we injected groups of NZB/W mice with low-dose (1,500 units/day) or high-dose (15,000 units/day) purified human recombinant IL-2. Parameters of active SLE and populations of splenocytes were not altered consistently by long-term treatment with either dose of IL-2.

Animals↗
PubMed1989

Anti-IgM treatment of C57BL/6-1pr/1pr mice: depletion of B cells reduces 1pr gene-induced lymphoproliferation and mononuclear cell vasculitis.

In order to study the role of B cells in autoimmune abnormalities observed in C57BL/6 mice bearing the autosomal mutant gene 1pr (lymphoproliferation), we treated mice from birth continuously with rabbit anti-IgM antiserum. Anti-IgM treatment resulted in the complete suppression of B cell development, documented by the absence of surface Ig-positive cells, the lack of lipopolysacchride-induced mitogenic responses, and the lack of autoantibody production. Although, anti-IgM-treated C57BL/6-1pr/1pr mice developed 1pr gene-associated lymphoproliferation due to the accumulation of Thy-1+, CD4-, CD8-, B220+ T lymphocytes in spleen and lymph nodes, the size of their spleen and lymph nodes was considerably smaller than that of normal rabbit serum-treated C57BL/6-1pr/1pr mice. Systemic vascular lesions associated with mononuclear cell infiltration were a little affected by anti-IgM treatment. This indicates that the development of mononuclear cell vasculitis in mice bearing the 1pr gene may be associated with the 1pr gene-induced lymphoproliferation and is independent of B cells and autoantibody production.

Animals↗
PubMed1988

Igh-C allotype-linked control of anti-DNA production and clonotype expression in mice infected with Plasmodium yoelii.

The infection of nonlethal strain of Plasmodium yoelii induces the formation of IgG anti-DNA antibodies as a result of polyclonal B cell activation. By using various nonautoimmune strains of mice including H-2 or Igh congenic or recombinant mice, the levels and clonotypes of anti-DNA antibodies elicited by the malaria infection were analyzed in relation to the expression of the MHC or Igh gene. Our results showed there were little, if any, differences in serum anti-DNA levels and their clonotypes among B10 and B6 H-2 congenic mice. In contrast, malaria-induced IgG anti-DNA responses markedly differed quantitatively and clonotypically between murine strains bearing the Ighb allotype and those bearing the Igha, Ighj, Ighd, or Ighn allotype. The latter group of mice produced approximately 5 to 10 times more IgG anti-DNA antibodies than the former group of mice. Clonotypically, mice bearing the Ighb allotype developed high alkaline anti-DNA antibodies of pH 8.0 to 8.5, whereas non-Ighb mice failed to express such alkaline anti-DNA spectrotypes, and exhibited more neutral spectrotypes (pH 7.0 to 8.0). Studies on the Igh recombinant mice indicated that the observed quantitative and clonotypical differences in IgG anti-DNA production was not associated with the variable region, but with the constant region of the Igh gene complex. Our results have suggested that IgG anti-DNA responses occurring as a result of polyclonal B cell activation during the course of malaria infection markedly differs quantitatively and clonotypically among murine strains and appear to be controlled at least in part by the Igh-C gene or gene(s) closely linked to it.

Animals↗
PubMed1988

Recombinant murine IL-3 fails to stimulate T or B lymphopoiesis in vivo, but enhances immune responses to T cell-dependent antigens.

We have explored the in vivo effect of IL-3 on the lymphopoiesis and humoral responses of mice bearing osmotic minipumps loaded with murine rIL-3 for 1 to 4 wk. A marked splenomegaly due to the accumulation of hemopoietic precursors was seen, but no increase was found in the lymphoid organs in the total number of cells belonging to the T or B lymphocyte lineage, i.e., of L3T4+ or Lyt-2+, or of allospecific cytotoxic T lymphocyte precursor for the T lineage, or of sIg+ or B220+ cells, or of B colony-forming cells for the B lineage; total activity of natural killer and lymphokine-activated killer cells was decreased. In contrast to the splenomegaly, a marked diminution in the number of thymocytes was observed, suggesting that rIL-3 in large amounts does suppress the T lymphopoiesis, perhaps as the result of the selective stimulation of early progenitor cells toward the hemopoietic pathway. rIL-3 perfusion during immunization increased the IgM and IgG responses to a T cell-dependent antigen, human IgG, and prevented tolerance induction by the deaggregated human IgG, although in the same conditions it did not modify the response to a T cell-independent antigen. Our results suggest that in vivo IL-3 does not act directly on lymphocytes or their precursors, but may potentiate the humoral immune response to T cell-dependent antigens, presumably by acting on accessory cells.

Animals↗
PubMed1988

The Y chromosome from autoimmune BXSB/MpJ mice induces a lupus-like syndrome in (NZW x C57BL/6)F1 male mice, but not in C57BL/6 male mice.

The Y chromosome of the BXSB mouse has been shown to be responsible for the acceleration of lupus-like autoimmune syndrome in inbred BXSB mice and in their F1 hybrids with NZB or NZW mice. To further define the role of this as yet unidentified gene linked to the BXSB Y chromosome, designated Yaa (Y chromosome-linked autoimmune acceleration), the Y chromosome was transferred from the BXSB strain to nonautoimmune C57BL/6 (B6) mice. The effect of the Yaa gene on the autoantibody formation and the development of glomerulonephritis was investigated in B6 mice and in their F1 hybrids with NZW mice. The presence of the BXSB Y chromosome was not able to induce significant autoimmune responses in B6 mice. However, (NZW x B6)F1 males bearing the BXSB Y chromosome developed a severe lupus-like autoimmune syndrome, as documented by the production of anti-DNA antibodies and gp70-anti-gp70 immune complexes and the development of lethal lupus nephritis. Both sexes of (NZW x B6)F1 hybrids without the BXSB Y chromosome were essentially normal. Our results suggest that (a) the BXSB Y chromosome by itself is not sufficient to initiate autoimmune responses in nonautoimmune B6 mice, and (b) it is able to induce autoimmune responses in mice potentially capable of developing the disease, but whose autosomal abnormality by itself is not sufficient to develop autoimmune diseases.

Animals↗
PubMed1988

Selective production of interleukin 3 (IL3) and granulocyte-macrophage colony-stimulating factor (GM-CSF) in vitro by murine L3T4+ T cells: lack of spontaneous IL3 and GM-CSF production by Ly-2-/L3T4- lpr subset.

Murine spleen and lymph node L3T4+ T cells were found to spontaneously produce high levels of interleukin 3 (IL3) and granulocyte-macrophage colony-stimulating factor (GM-CSF) in cultures containing 10% fetal calf serum (FCS) in the absence of other stimulation. The IL3 and GM-CSF activities in culture supernatants peake between the fifth and seventh day of culture. The specificity of the bioassays was attested by the use of rabbit anti-IL3 and anti-GM-CSF antibodies, as well as by the detection of a maximal accumulation of IL3 and GM-CSF mRNA on the fourth day. In contrast, no significant activities of IL2, IL4 or interferon-gamma were detected in these culture supernatants. The markedly limited production of IL3 and GM-CSF in cultures performed in 1% autologous normal mouse serum and the inhibitory effect of anti-Ia or anti-L3T4 monoclonal antibody strongly suggest that the selective production of most, if not all IL3 and GM-CSF by L3T4+ T cells is a result of activation of L3T4+ T cells by fetal calf serum. All the strains of mice tested except athymic nude mice produced substantial amounts of IL3 and GM-CSF during the culture. This is in contrast to a previous report (Palacios, Eur. J. Immunol. 1984. 14: 599), indicating that only spleen cells of the MRL strain homozygous for the lpr gene spontaneously release IL3 in cultures. We found that spleen and lymph node cells from MRL/MpJ-lpr/lpr or C57BL/6J-lpr/lpr mice released, in fact, much less IL3 and GM-CSF in cultures. This was, however, due to the high proportion of the peculiar lpr Ly-2-/L3T4-T cells in spleen and lymph nodes, since after depletion of this lpr T cell subset, lymph node cells from C57BL/6J-lpr/lpr mice produced IL3 and GM-CSF at levels comparable to those in C57BL/6J-+/+ mice. These results further support the notion that the lpr Ly-2-/L3T4- T cell subset is immunologically nonfunctional and its accumulation dilutes functional L3T4+ T cells in mice bearing the lpr mutation.

Animals↗
PubMed1988

A member of a new VH gene family encodes antibromelinized mouse red blood cell autoantibodies.

A cDNA clone encoding the variable region of the heavy chain of a BALB/c antibromelinized mouse red blood cell (BrMRBC) monoclonal antibody has been characterized. The nucleic acid sequence indicates that the variable region of the heavy chain is likely encoded by variable-VCP12, diversity-DSP 2 (5, 7 or 8) and joining-JH1 germ-line genes. An identical combination of V genes was observed for six other CBA/J and NZB anti-BrMRBC hybridomas. The BALB/c VCP12 nucleotide sequence is less than 80% homologous to members of the 10 known VH families. Moreover, the genomic restriction fragments detected under moderate stringency conditions with the radiolabeled cDNA probe did not correspond to those obtained with probes of the most homologous VH families (7183 and X24). The results indicate that the VCP12 gene defines a new VH family which we propose to designate VH11. The observation of 1, 2 or 3 genomic restriction fragments at the most, with mice bearing the Igh-Vd or j, Igh-Va or b or Igh-Vc haplotypes, suggests the existence of a few VCP12-related genes.

Animals↗
PubMed1988

Effect of helper and/or cytotoxic T-lymphocyte depletion on low-dose streptozocin-induced diabetes in C57BL/6J mice.

The low-dose streptozocin (STZ) model of diabetes has been reported to involve direct STZ beta-cytotoxicity and/or immunologically mediated beta-cell destruction. Because the T-lymphocyte dependency of such a model is controversial, we further assessed the role of T-lymphocytes by determining the occurrence and magnitude of hyperglycemia as well as the pancreatic insulin contents in both STZ-injected nude C57BL/6J male mice and STZ-injected euthymic C57BL/6J male mice selectively depleted in helper and/or cytotoxic T-lymphocytes with monoclonal antibodies (MoAbs). The effectiveness of MoAb treatment was assessed in lymph node cells by flow-microfluorometry analysis and in spleen cells by concanavalin A stimulation, allospecific cytotoxic T-lymphocyte activity, and T-lymphocyte lymphokine production. Sixteen days after the first STZ injection, hyperglycemia (plasma glucose greater than 200 mg/dl) occurred in significantly fewer helper T-lymphocyte-depleted mice (P less than .005) or helper and cytotoxic T-lymphocyte-depleted mice (P less than .001) than in non-MoAb-treated mice. However, a progressive increase in the number of mice with hyperglycemia ensued in all MoAb-treated groups, and 2 mo after STZ was administered, the prevalence of hyperglycemia, mean plasma glucose levels, and pancreatic insulin contents did not differ significantly from the values obtained in the non-MoAb-treated animals. Similarly, STZ-injected C57BL/6J male nude mice developed hyperglycemia that was associated with a marked decrease in pancreatic insulin contents on a time course comparable with that of STZ-injected euthymic C57BL/6J male mice depleted in helper or in helper and cytotoxic T-lymphocytes by MoAbs.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1988

Resistance to tolerance induction to human gammaglobulin (HGG) in autoimmune BXSB/MpJ mice: functional analysis of antigen-presenting cells and HGG-specific T helper cells.

Autoimmune male, but not female, BXSB/MpJ mice resist the induction of tolerance to human gammaglobulin (HGG). To better define the cellular basis for this abnormality, we have compared in vitro the functional activity of antigen-presenting cells between tolerant-resistant male and susceptible female mice, and evaluated in vivo the immunological status of HGG-specific T helper cells in male BXSB mice after the treatment with monomeric deaggregated HGG (DHGG). Our results indicated that there were no significant differences in the ability of male and female antigen-presenting cells to present HGG to either male or female HGG-specific immune T blasts. Further, thymic cells from DHGG-treated male BXSB mice failed to support anti-HGG antibody responses when adoptively transferred with non-treated bone marrow cells, and that draining lymph node cells from male as well as female BXSB mice treated with DHGG prior to the challenge of immunogenic aggregated HGG (AHGG) were unable to exhibit the proliferation upon in vitro restimulation with AHGG. This indicates that HGG-specific T helper cells were indeed tolerized in tolerant-resistant male BXSB mice by the treatment with DHGG. In contrast, when the tolerance induction was inhibited by bacterial lipopolysaccharides, HGG-specific T helper cells from such mice exhibited a marked proliferation upon in vitro restimulation with AHGG. These results suggest that the cellular defect in the abnormal resistance to tolerance induction to HGG in male BXSB mice resides neither in the antigen-presenting cells nor in the HGG-specific T helper cells, and that the mechanism responsible for this abnormality in male BXSB mice is basically different from that involved when tolerance is overcome by lipopolysaccharide.

Animals↗
PubMed1988

Enzyme-linked immunosorbent assay for detection of retroviral gp70 and gp70-anti-gp70 immune complexes in sera from SLE mice.

Since a retroviral envelope glycoprotein, gp70, present in sera is prominently involved in the pathogenesis of murine systemic lupus erythematosus (SLE), the detection of gp70-anti-gp70 immune complexes (gp70 IC) is particularly useful for the study of murine SLE. To facilitate the detection of gp70 and gp70 IC, we have developed a simple and sensitive enzyme-linked immunosorbent assay (ELISA). Using an affinity column coupled with whole mouse serum proteins containing serum gp70 or with Rauscher murine leukaemia virus (MuLV), antibodies specific to serum gp70 or to Rauscher MuLV gp70 were purified from hyperimmune goat anti-Rauscher MuLV gp70 antisera. Only affinity-purified anti-serum gp70 fraction, but not anti-Rauscher MuLV gp70 fraction, was able to detect serum gp70 efficiently in the ELISA, because only a minor fraction of goat anti-Rauscher MuLV gp70 antibodies is cross-reacting with serum gp70. This procedure could be applied to other antigen-antibody systems, in which only antibodies to heterologous cross-reacting antigens are available, to detect free and antibody-complexed antigens in pathological sera.

Animals↗
PubMed1987

Autoimmune syndrome after induction of neonatal tolerance to alloantigens: effects of in vivo treatment with anti-T cell subset monoclonal antibodies.

BALB/c (H-2d) mice rendered tolerant to h-2b alloantigens by neonatal injection of semiallogeneic (C57BL/6 X BALB/c)F1 spleen cells develop autoimmune features due to an abnormal activation of persisting F1 donor B cells. The role of T cells in this autoimmune syndrome was studied by in vivo treatment of tolerant mice with anti-L3T4(GK-1.5) or anti-Ly-2 (H-35-17.2) monoclonal antibodies. The treatment of tolerant mice from day 2 to day 21 of life with anti-L3T4 MAb completely prevented the occurrence of circulating immune complexes of anti-ssDNA anti-Sm and anti-hapten (FITC) IgG antibodies as well as the glomerular deposition of Ig that were usually seen in untreated tolerant mice. This effect persisted for at least 6 wk after stopping this treatment. When the injections of anti-L3T4 MAb were delayed until day 15 of life, a very significant decrease of the autoimmune manifestations was still observed. Treatment of tolerant mice with anti-Ly-2 MAb during the same period had no effects on the autoimmune disease as compared with untreated tolerant mice. No effects on the maintenance of tolerance vs H-2b alloantigens were observed after treatment with anti-L3T4 MAb, as followed by the decrease of CTL and CTL-p alloreactivity and by the persistence of F1 donor B cells, indicated by the presence of Ig bearing the Ighb donor allotype. These results suggest the existence of interactions between L3T4+ T cells and persisting autoreactive B cells from F1 donor origin in the development of the autoimmune syndrome after neonatal induction of transplantation tolerance.

Animals↗
PubMed1987

Treatment with high doses of anti-IgM prevents, but with lower doses accelerates autoimmune disease in (NZW x BXSB)F1 hybrid mice.

We have treated autoimmune-prone (NZW x BXSB)F1 hybrid mice with polyclonal rabbit anti-mouse IgM antibodies starting from birth to define conditions leading to quantitative and functional elimination of the B cell compartment and to determine the effect of anti-IgM treatment on the development of autoimmune disease. A maintenance dose of anti-IgM antibodies (600 micrograms/wk), which efficiently induced B cell depletion in various non-autoimmune strains of mice, was not sufficient to deplete B cells from autoimmune-prone (NZW x BXSB)F1 mice. (NZW x BXSB)F1 mice required approximately twice as many anti-IgM antibodies (1200 micrograms/wk) to maintain the suppression of B cell development. Continuous treatment with the sub-suppressive dose of anti-IgM antibodies led to a marked acceleration of autoimmune disease in (NZW x BXSB)F1 mice. In contrast, elimination of B cells in (NZW x BXSB)F1 mice with a higher dose of anti-IgM antibodies (1200 micrograms/wk) completely prevented autoantibody production, immune complex formation, and development of glomerulonephritis and vascular lesions associated with mononuclear cell infiltrations. Our results are a direct demonstration of the primary role of autoantibodies for the development of various tissue lesions seen in systemic lupus erythematosus (SLE) and indicates that autoreactive effector T cells, if they exist, play no major direct role in the pathogenesis of SLE, at least in (NZW x BXSB)F1 hybrid mice.

Animals↗