[The relationships of sex hormone binding globulin (SHBG) with high density lipoprotein cholesterol and fasting insulin in healthy men]

The relationships of sex hormone binding globulin (SHBG) with high density lipoprotein cholesterol (HDL-C) and fasting insulin (IRI) were investigated in healthy employed men (n = 235). In simple correlation analysis, the SHBG was positively related to total cholesterol and HDL-C, and negatively related to IRI. There were no relationships among SHBG, triglyceride and fasting blood glucose. In multiple linear regression analysis, SHBG was one of determinant of HDL-C, but not IRI. From these results, it was suggested that SHBG was one of the determinants of HDL-C level in healthy men.

Relationships of lipid and glucose metabolism with waist-hip ratio and physical fitness in obese men

The waist-hip ratio (WHR) is an indirect index of abdominal type obesity which has been shown to be strongly correlated with the risk of coronary heart disease. Empirically, men who have a higher WHR seem to have a lower level of physical fitness. In the present study, the relationships of lipid and glucose metabolism with WHR and physical fitness were examined in 207 Japanese obese men. Physical fitness was evaluated by the oxygen uptake at the onset of blood lactate accumulation (OBLA-VO2; ml/kg/min) which corresponds to 4 mmol/l of blood lactate during graded exercise test and is one of the best indicators of the muscle oxidative capacity. The WHR and percentage of body fat (% body fat) were significantly correlated with OBLA-VO2. The WHR and % body fat were significantly related to each other. After adjusting for % body fat, a significant negative correlation was observed between the WHR and OBLA-VO2 (r = -0.24; P < 0.05). A multiple linear regression was calculated for parameters relating to lipids, and glucose and insulin areas separately, when the WHR, OBLA-VO2, % body fat and age were entered as independent variables. OBLA-VO2 significantly showed a negative relationship with triglyceride (TG), HDL-C/total cholesterol, and the insulin area, while the WHR was only independently related to TG. From these results, we conclude that the physical fitness level evaluated by OBLA-VO2, which represents the capacity of the aerobic metabolism in muscle, may thus be a determinant of lipid and glucose metabolism in obese men.

Autocorrelation of short-term and daily average exposure levels in workplaces

Based on workplace exposure data for 16 worker-chemical combinations, the degree of autocorrelation in a series of short-term time-weighted average (TWA) exposure concentrations (7.5-min, 15-min, 30-min, and 60-min TWAs) was investigated. For 7.5-min and 15-min TWAs, consecutive values generally exhibited no correlation or positive correlation, but not negative correlation. Consecutive 30-min TWAs and 60-min TWAs showed either positive correlation, negative correlations, or no correlation. Autocorrelation functions displayed various patterns that depended on the exposure time series. The mean of the autocorrelation coefficients across all worker-chemical combinations was similar to an exponential function, which signifies that the degree of autocorrelation, on average, decreased as the interval between two averaging periods increased. Autocorrelation in a series of 8-hr TWAs also was analyzed for 10 worker-chemical combinations. In general, little autocorrelation was observed. Based on this analysis, the authors discuss a sampling strategy that, on average, would minimize the degree of correlation between measurements of short-term TWAs.

[Estimation of asbestos exposure among workers repairing asbestos cement pipes used for conduits]

Asbestos cement pipes (ACPs) containing 15 to 20% chrysotile or crocidolite have been used for underground conduits. Even today 16.2% of all conduits in Japan are ACPs, though the production of ACPs was suspended in 1985. When such a conduit is accidentally damaged the workers belonging to the Waterworks Bureau of a local government cut off the damaged conduit using a high-speed disk cutter and replace it with a new conduit. This operation develops a cloud of dust and the workers involved run the risk of asbestos exposure. It was the aim of the present study to estimate asbestos exposure levels among these workers. First, in the experiment, we established the typical working conditions and requested an experienced worker to cut an ACP using a high-speed disc cutter in a hole dug in the ground as he routinely does. The experiment was repeated three times. During a bout of each experiment, dust was sampled at several points both inside and outside the hole. Second, a self-administered questionnaire survey was conducted to obtain information from the workers regarding their working conditions in cutting ACPs. The subjects of the survey were 1,048 men belonging to conduit repair sections of the Waterworks Bureau of 119 local governments. The results obtained can be summarized as follows. 1) Each bout of cutting ACPs required about five minutes. The concentration of asbestos fibers longer than 5 microns with 3:1 aspect ratio ranged from 48 to 170 fibers/ml (92 fibers/ml on an average) inside and 1.7 to 15 fibers/ml outside the hole. The concentration inside the hole exceeded the ceiling limit (10 fibers/ml) recommended for asbestos by the Japanese Association of Industrial Health. A concentration of 92 fibers/ml is equivalent to 0.96 fibers/ml as 8-h time-weighted average. 2) The number of subjects with experience of cutting ACPs was 849 (81.0%). The average length of service in conduit repair section was 14.2 yr. Based on the information obtained from each subject regarding the average working days per yr for each decade from 1946, the cumulative days to date expended in cutting ACPs was estimated to average 235 d, that is, 17 d per yr. Only 18.1% of the subjects used a protective respiratory device.(ABSTRACT TRUNCATED AT 400 WORDS)

The expression of invasive behavior of differentiated squamous carcinoma cell line evaluated by an in vitro invasion model

In order to elucidate the factors contributory to the expression of invasiveness of oral squamous cell carcinoma, we conducted biochemical and morphological comparisons of well differentiated squamous carcinoma cell line OSC-19 (oral squamous cell carcinoma) and undifferentiated carcinoma cell line KB, both cultured on 3T3 cell-embedded collagen gel (in vitro invasion model). OSC-19 cells invaded 3T3 cell-embedded collagen gel, while KB cells and OSC-19 cells on 3T3 cell-free gel matrix were less invasive. Cultured OSC-19 cells were characterized by lower proliferating activity, lower secretion of laminin and higher secretion of fibronectin than those of KB cells. Although the basement membrane with deposition of laminin and type IV collagen was formed, it was discontinuous at the invasion front. Gelatin zymography and western blotting showed matrix metalloproteinases (MMP), i.e., 72 kDa gelatinase (MMP-2) and 92 kDa gelatinase (MMP-9). Gelatinolytic activity was assayed, and was higher in OSC-19 cells than in KB cells or OSC-19 cells of the 3T3 cell-free model. By immunohistochemical analysis, MMP-2-positive cells were found scattered in both cell lines without any preferential localization, and the positivity for MMP-9 was localized in the invasion front of OSC-19 cells. These results strongly suggest that the invasiveness of squamous cell carcinoma is well correlated with cell-matrix adhesion by fibronectin and with focal elaboration of metalloproteinases, especially MMP-9, which play a major role in degrading the extracellular matrix components.

Enhancing effect of 17 beta-estradiol on human NK cell activity

The in vitro effect of 17 beta-estradiol on NK activity was studied. The proliferation and NK activity of YT-N17 (a human NK-like cell line) were enhanced by 17 beta-estradiol (E2), and the enhancement was blocked by tamoxifen (Tx), an antagonist of E2. On the contrary, other steroid hormones such as Tx, progesterone, and testosterone had no effect. YT-N17 contained 11.8 fmol/mg protein of estrogen receptor (mean of two independent assays), a value which was 5-10-fold higher than that of other hematopoietic cell lines. An enhancement of NK activity by E2 was also seen in large granular lymphocytes obtained from normal subjects, and it was again suppressed by Tx. These data suggest that E2 is one of the activating factors for NK/LGL cells.

A synthetic analogue for the active site of plant-type ferredoxin: two different coordination isomers by a four-cys-containing [20]-peptide

The (Fe2S2)2+ complex of an artificial 20-peptide ligand, Ac-Pro-Tyr-Ser-Cys-Arg-Ala-Gly-Ala-Cys-Ser-Thr-Cys-Ala-Gly-Pro-Leu-Leu-T hr-Cys- Val-NH2, containing an invariant Cys-A-B-C-D-Cys-X-Y-Cys (A, B, C, D, X, Y = amino acid residues) fragment of plant-type ferredoxins was synthesized by a ligand exchange method with [Fe2S2(S-t-Bu)4]2-. 1H-nmr spectroscopic and electrochemical data of the complex indicate the presence of two coordination isomers. One of them having a Cys-X-Y-Cys bridging coordination to the two Fe(III) ions, has the (Fe2S2)2+ core environment similar to those of the denatured plant-type ferredoxins and exhibits a positive shifted redox potential at -0.64 V vs saturated colonel electrode (SCE) in N,N-dimethylformamide (DMF). Another isomer with the Cys-A-B-C-D-Cys bridging coordination shows a negative redox potential at -0.96 V vs SCE in DMF.

The presence of antibodies to purified p24gag protein of HTLV-I in sera of patients with systemic lupus erythematosus (SLE)

Sera of patients with systemic lupus erythematosus (SLE) were tested for their reactivity to HTLV-I by western blotting (WB). Seven (18%) of 40 SLE serum samples reacted to the p24gag protein of HTLV-I by WB using purified gag antigens. The specificity of anti-p24gag antibodies in the SLE sera was confirmed by competitive inhibition on WB. Two of the seven patients were shown to be HTLV-I carriers, because HTLV-I infected T cell lines were easily established from their peripheral blood mononuclear cells (PBMC). Except for these two carrier patients, the gag proteins were not detected in the lysates of PBMC by WB using anti-p24gag and anti-p19gag monoclonal antibodies. The gag and pX genes of HTLV-I were not detected by PCR in PBMC of the SLE patients, with the exception of the 2 HTLV-I carrier patients. These results show no direct involvement of HTLV-I in the etiology of SLE. However, the existence of a specific antibody to p24gag in the sera of some of the noncarrier SLE patients suggests a crossreactivity to either unknown viruses or some autoantigens.

In vitro induction of IgG anti-DNA antibody from high density B cells of systemic lupus erythematosus patients by an HLA DR-restricted T cell clone

An HLA-DR restricted T cell clone (26G11) which recognized a lymphoid cell-derived autoantigen associated with DR4 molecule was shown to induce not only autologous but also allogenic DR4+ B cells to produce large amounts of antibodies of the IgG and IgM classes. Using the helper activity of this clone, we investigated the mechanism of anti-DNA antibody production in DR-matched patients with systemic lupus erythematosus (SLE). When cultured with 26G11 cells, B cells from DR-matched normal control subjects produced large amounts of IgM anti-DNA antibody, but did not produce IgG anti-DNA antibody which is thought to have a pathological role in SLE. In contrast, B cells from DR-matched patients with active SLE spontaneously produced a fairly large amount of IgG anti-DNA antibody, and the production was augmented by the T cell clone. Little IgG anti-DNA antibody was produced by the B cells of patients with inactive SLE in either the presence or absence of T cell clone. We next fractionated B cells into low density B (LD-B) and high density B (HD-B) cells by centrifugation on discontinuous Percoll density gradients. IgG anti-DNA antibody was spontaneously produced by LD-B cells of active SLE patients but not by those either of inactive SLE patients or normal controls. On the other hand, although IgG anti-DNA antibody was not spontaneously produced by the HD-B cells of both active and inactive SLE patients, it could easily be induced by their culture with the T cell clone. Our results clearly show the existence of IgG anti-DNA antibody-producing B cells in the peripheral blood of SLE patients irrespective of their disease activity and suggest that autoreactive T cells may play a pathogenic role in SLE through the induction of autoantibody production.

Determination of exposure to cobalt and nickel in the atmosphere in the hard metal industry

Cobalt and nickel, matrices of hard metal, have been shown to be respiratory sensitizers. Airborne dust at hard metal-grinding worksites in a factor with a work-force of about 180 grinders was analysed for cobalt and nickel. The electron-microscopic X-ray microanalysis of airborne dust particles demonstrated that they had the same metallic components as hard metal products. Andersen sampling revealed that 66% of total dust was respirable (< 7 microns). Consecutive personal sampling for individuals indicated log-normally distributed concentrations of total dust and cobalt. Of the workers surveyed, 12% (16 out of 133) were exposed to cobalt at more than 50 micrograms m-3, while 1.5% (two out of 133) were exposed to nickel concentrations of more than 50 micrograms m-3. A correlation between cobalt exposure concentrations and nickel concentrations for individuals was significant and positive. Further improvement of the working environment is necessary because of the hazard caused by exposure to cobalt and nickel.

Induction and function of Fc epsilon RII on YT cells; possible role of ADF/thioredoxin in Fc epsilon RII expression

The regulation of low-affinity Fc receptor for IgE (Fc epsilon RII) and the characteristics of both membrane and soluble forms of Fc epsilon RII were studied using YT cell line. We found that YT cells, a human NK like cell line, expressed Fc epsilon RII after IL-1 stimulation. Cross-linking of Fc epsilon RII on IL-1-stimulated YT cells as well as the transfectant of Fc epsilon RII-cDNA (YTSER) resulted in the up-regulation of IL-2R alpha (p55/Tac). A 59 kDa protein phosphorylated at tyrosine residues was co-immunoprecipitated with Fc epsilon RII from YTSER lysate using H107 anti-Fc epsilon RII mAb. YTSER not only expressed Fc epsilon RII on their surface but also secreted soluble form of Fc epsilon RII (sFc epsilon RII/sCD23; IgE binding factor). Affinity purification revealed that sFc epsilon RII released from YTSER is heterogeneous and consisted of several proteins differing in molecular weight. Both EBV+ B cells and HTLV-1+ T cells are high producers of ATL derived factor (ADF)/thioredoxin (TRX) and express Fc epsilon RII and IL-2R alpha respectively. To clarify the mechanism of Fc epsilon RII and IL-2R alpha induction by ADF/TRX, we examined the effect of ADF/TRX on the bindability of nuclear factor kappa B (NF-kappa B), which is known to regulate IL-2R alpha gene expression. In the gel shift assay, ADF/TRX was shown to enhance the bindability of NF-kappa B to its responsive element.

Effects of isopropanol on the development of inflammatory reactions in rats

The effects of isopropanol on the development of inflammation were studied in rats. Isopropanol inhibited both the histamine-induced increase in cutaneous vascular permeability and the carrageenan-induced plasma exudation into the pleural cavity. The lipopolysaccharide-induced leucocyte emigration into the subcutaneous pouch was unaffected by isopropanol, but the leucocyte emigration of carrageenan-induced pleural inflammation was markedly inhibited by isopropanol. In contrast, when isopropanol was administered with an anti-inflammatory drug (indomethacin or dexamethasone), it enhanced the pleural inflammatory reaction. These results suggest that isopropanol may exert toxic effects through interference with the normal processes of inflammation and interaction with other agents that affect inflammatory reactions.

[Detection of Campylobacter species by using polymerase chain reaction and nonradioactive labeled DNA probe]

We have detected Campylobacter species which are now recognized as major pathogens of acute diarrheal disease in humans using polymerase chain reaction (PCR) and a nonradioactive labeled DNA probe. Diagnosis of Campylobacter enteritis without doing culture from stool samples is of great benefit in the laboratory. Two oligonucleotide primers (20 mer) complementary to a unique sequence of the DNA encoding ribosomal RNA (rRNA) of Campylobacter jejuni for PCR were synthesized by solid-phase phosphoamidite method. Amplified target DNA of 275 base pairs could be resolved on ethidium bromide-stained gels, and hybridized with an oligodeoxynucleotide probe (28 mer) conjugated to alkaline phosphatase. In identification experiments, it was shown that the nonradioactive probe was hybridized to clinical strains of C. jejuni (104), C. coli (5), C. laridis (5), C. hyointestinalis (1) and C. fetus subsp. fetus (1) with an accuracy of 99-100%, while it was not for Helicobacter pylori. Further, there was no evidence of amplification in strains of K. pneumoniae, S. marcescens and E. coli. Using direct detection to stool specimens, this method could be performed in C. jejuni in 39 of 43 culture-positive specimens (91%), and in 19 of 141 culture-negative specimens (13.5%), respectively. The results of this comparative study suggested that the DNA probe assay became a rapid and reliable technique to confirm culture of Campylobacter species.

The incidence of Listeria species in retail foods in Japan

Meat, fish and vegetable products obtained at retail shops in or around Tokyo were examined for Listeria contamination. Listeria spp. were isolated from 43 (56.6%) out of 76 samples of meat products. L. monocytogenes occurred in 26 (34%) of the samples, L. monocytogenes was isolated from 7 (6.1%) out of 114 samples of fish and fish products including 'ready-to-eat' foods. Listeria was not isolated from any of 21 samples of vegetable and vegetable product including 'ready-to-eat' foods investigated.

Antigen-induced apoptotic death of Ly-1 B cells responsible for autoimmune disease in transgenic mice

Studies on transgenic mice expressing immunoglobulins against self-antigens have shown that self-tolerance is maintained by active elimination (clonal deletion), functional inactivation (clonal anergy) of self-reactive B cells, or a combination of both. We have established and characterized a transgenic mouse line expressing an anti-erythrocyte autoantibody. In contrast to other autoantibody transgenic lines, about 50% of the animals of this transgenic line suffer from autoimmune disease, indicating a loss of self-tolerance. Here we show that peritoneal Ly-1 B cells (also known as B-1 cells) are responsible for this autoimmune disease in our transgenic mice. A few self-reactive Ly-1 B cells that have somehow escaped the deletion mechanism expand in the peritoneum because of the absence of self-antigen. These Ly-1 B cells are eliminated in vivo by apoptosis once exposed to self-antigen. On the basis of these results we propose a novel autoantibody production mechanism whereby self-reactive B cells sequestered in compartments free of self-antigens may survive, proliferate and be activated for generation of pathogenic autoantibodies in autoimmune diseases.

Biliary immune response to orally presented food antigen, ovomucoid, and its potentiation by cholera toxin B subunit

To clarify the biliary immune response against food antigen, we studied biliary antibody response to intravenous and oral primary immunization with ovomucoid (OM) and the effects of cholera toxin B subunit (CTB) on the oral response in mice. Specific antibodies against OM were induced in biliary and serum immunoglobulin (Ig) A, IgG and IgM by intravenous (i.v.) administration of the antigen. However, the antibodies were induced only in biliary Igs, but not in serum Igs, by oral intubation of the antigen. The higher levels of anti-OM in bile than in serum observed in the oral group may favour the assumption that antigen-stimulated lymphoid cells migrate to the liver, gall bladder or bile duct where they produce antibody. Both serum and biliary anti-OM responses to oral immunization were potentiated remarkably by oral administration of CTB with the antigen, the IgM anti-OM response being potentiated to the largest extent. In the CTB-treated mice, the IgA anti-OM level was higher in bile than in serum. Serum level of IgG anti-OM was much lower in the CTB-treated mice than in the i.v.-immunized mice, but the biliary level of IgG anti-OM in the CTB-treated mice was comparable to that in the i.v.-immunized mice. The relationship between serum and biliary IgA and IgG antibodies suggests that CTB potentiates biliary anti-OM responses not solely through increasing systemic levels of the antibodies but through modulating the processes specific to mucosal presentation of antigen.

[Detection of methicillin-resistant Staphylococcus aureus using PCR and non-radioactive DNA probe]

Two commonly used diagnostic tests for Staphylococcus aureus (MRSA) are cultivation of bacteria from clinical samples on mannitol-salt agar plate or on MRSA-screen agar plate with oxacillin. However, the use of PCR and DNA probes is considered more rapid and sensitive, as staphylococcal cells have high resistance to beta-lactam due to the novel penicillin-binding protein, PBP2'. Therefore, three different pairs of DNA primers (P1F-P1R, P2F-P2R and P3F-P3R) complementary with unique regions of the MRSA PBP2' gene were synthesized for use in polymerase chain reactions with DNA of MRSA. Amplified target DNA of 466, 480 and 630 bp could be resolved on ethidium bromide-stained gels, and hybridized with DNA probes conjugated to alkaline phosphatase. When applied to pure cultures on the MRSA screen agar, the DNA probes detected MRSA in 180 of 196 (P1F-P1R), 72 of 83 (P2F-P2R) and 66 of 71 (P3F-P3R) culture-positive specimens (accuracy range, 86.7-93.0%), while 61.6-89.3% of MRSA were detectable in culture-positive specimens streaked on the mannitol-salt agar. When applied directly to clinical samples, this DNA probe assay detected MRSA in culture-positive specimens within an accuracy range of 50.0-79.3%. It was thus clear that comparison of cultivation and DNA hybridization results yields good correlation with respect to detection of MRSA. These results suggest that the DNA probe assay may be useful in complementing existing culture techniques.

Fluctuations of occupational exposure indices to mixtures

In workplaces, two or more hazardous substances are often used simultaneously. Daily average exposure to each can vary considerably from day to day, and thus indices (Emix) combining exposures to all substances used must vary in a more complex manner. In this study, we examined the between-days distributions of Emix using occupational data for five workers exposed to two or more organic solvents, and found Emix to be log-normally distributed. To describe the between-days fluctuation of Emix, we propose a new model in which the causes of fluctuation were classified as a Specific Factor and a Common Factor. We also present a new method for estimating the distribution of Emix. The usefulness of our new model and new method is shown by their application to actual data.

The development of a revolving personal sampler

The American Conference of Governmental Industrial Hygienists recommends the use of threshold limit value-short-term exposure limit (TLV-STEL) and ceiling limit (TLV-C) as guide-lines to prevent workers from irritation, chronic or irreversible tissue damage, and narcosis caused by intense exposures to hazardous substances for short periods. To evaluate whether a worker's exposure level is within the specified limit, it is desirable to measure every 15-min time-weighted average concentration (15-min TWA) during a workday. The authors developed a revolving personal sampler that can collect consecutive short-term exposure samples. A recovery test of toluene of various concentrations was conducted by using this sampler. Toluene concentrations in the test atmosphere were 10, 50, 100, 200, and 400 ppm. The test results showed that the mean recovery at each concentration was 97.7% to 100.0%, and the coefficient of variation was 0.008 to 0.015. The revolving personal sampler can be used to monitor every 15-min TWA of a worker.

Demonstration of the requirement for self antigen in the activation of autoreactive T cells

An HLA-DR4-restricted T cell clone (26G11), which was reactive to autologous non-T cells without any nominal antigens, was established from an unimmunized normal subject that was DR1/4 positive. The reactivity of the clone was examined against L cells (LDR4) transfected with the particular DR4 genes obtained from the same subject. 26G11 cells proliferated slightly in response to LDR4 cells, but the proliferation was markedly augmented by the addition of cell lysate from an autologous B cell line. In addition, 26G11 cells killed LRD4 cells sensitized by preincubation with the cell lysate more efficiently than LDR4 cells without treatment. When LDR4 cells were preincubated with cell lysate from allogenic B cell lines, effective killing of the target cells by clone 26G11 was also observed. These data strongly suggest that this autoreactive T cell clone (26G11) recognizes endogenous antigen in the context of the DR4 molecule. This directly demonstrates the requirement for self antigen in the activation of human autoreactive T cells from a normal subject.

[Assessment of occupational exposures to industrial hazardous substances. V. A proposed method for evaluating employee's exposure averages (8-h TWAs) using a single day measurement]

Daily exposure averages (8-h TWAs) to hazardous substances may vary considerably day to day, even though a worker is engaged in the same job. Previously we proposed a method to evaluate a long-term exposure condition with interday fluctuation using some exposure measurements. As it is assumed that 8-h TWAs are log-normally distributed, geometric standard deviation (sigma g) representing true interday fluctuation of 8-h TWAs should be estimated. If a single day's 8-h TWA of a worker is measured, sigma g of his own distribution of 8-h TWAs cannot be estimated. Therefore, to evaluate a long-term condition using a single day's 8-h TWA, representative sigma g in all industrial workplaces must be determined beforehand. To investigate sigma g observed in many industrial workplaces, two days' 8-h TWAs of each worker were measured in a week on 260 workers exposed to 19 hazardous substances. Sg2 (geometric standard deviation estimated by two samples) ranged from 1.00 to 8.22 with a median of 1.47 and a 90% upper limit of 2.47. Transforming Sg2 into sigma g, median and 90% upper limit of sigma g were 1.75 and 2.47, respectively. According to a classification scheme in the proposed method, exposure levels (I to III) were calculated using sigma g of 1.75 and 2.47. A long-term exposure condition to hazardous substances can be evaluated by comparing a single day's 8-h TWA with the exposure levels.

A transgenic model of autoimmune hemolytic anemia

We made double transgenic mice bearing immunoglobulin heavy and light chain genes encoding an autoantibody against the mouse erythrocyte by the cross of C57BL/6 mice carrying the transgene for each chain of the immunoglobulin. Although no obvious disorders were found in the single-chain transgenic mice, severely anemic symptoms were found in some of the double transgenic mice, in which most B cells express, at least on their surface, the autoantibody reactive to self-antigens on the erythrocyte. Individual double-transgenic mice showed a wide variation of phenotypes between severe anemia and no symptoms. Both deletion and anergy of autoreactive B cells were seen in each individual mouse, but their relative contribution to self-tolerance was variable and not directly related to the severity of anemia or the amount of the autoantibody produced. This transgenic system provides a good autoimmune disease model for exploring its onset mechanism, and means of its treatment and prevention.