| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
|
|
|
|||||||
|
|||||||||
* Department of Pathology and
Division of Rheumatology, Department of Internal Medicine, Juntendo University Graduate School of Medicine, Tokyo, Japan;
Toin Human Science and Technology Center, Toin University, Yokohama, Japan; and
Department of Infectious and Transplantation Immunology, Shinshu University Graduate School of Medicine, Matsumoto, Japan
 |
Abstract |
|---|
 Top Abstract IntroductionMaterials and MethodsResultsDiscussionReferences |
|---|
3.5 kb in the C1qa
upstream region of NZB mice. C1q levels in sera and culture
supernatants of LPS-stimulated peritoneal macrophages and
C1q messages in spleen cells were all lower in
disease-free young NZB and (NZB x NZW)F1 mice than in
age-matched non-autoimmune NZW and BALB/c mice. Quantitative trait loci
analysis using (NZB x NZW)F1 x NZW backcrosses
showed that NZB microsatellites in the vicinity of the
C1q allele on chromosome 4 were significantly linked to
low serum C1q levels and the development of nephritis. These data imply
that not only C1q deficiency but also regulatory region polymorphisms
down-regulating C1q levels may confer the risk for lupus nephritis by
reducing IC clearance and thus promoting IC deposition in
glomeruli. |
Introduction |
|---|
|
TopAbstractIntroductionMaterials and MethodsResultsDiscussionReferences |
|---|
Homozygous deficiencies of early complement components, including C1q, are frequently associated with SLE (2, 3, 4, 5, 6, 7, 8, 9). C1q-deficient mice are prone to glomerulonephritis with IC deposition (10). It has been postulated that deficiency in early complement components will result in impaired ability to clear ICs, leading to their tissue deposition, which triggers inflammation and tissue damage (8, 9). There are significantly greater numbers of glomerular apoptotic bodies in C1q-deficient mice compared with C1q-intact controls, thereby suggesting the important role of C1q in clearance of self-Ag-containing apoptotic bodies (10). Thus, C1q may also contribute to prevention of autoantibody responses to self-Ags derived from apoptotic bodies. All these findings suggest that the C1q gene deficiency is one underlying genetic factor for SLE susceptibility.
The molecular basis of C1q deficiency is single base-pair mutations leading to termination codons, frame shift, or amino acid exchange in each one of the three C1q genes (a, b, and c) associated with absence of detectable protein or expression of reduced levels of dysfunctional protein (5, 6, 11, 12). Although these homozygous C1q deficiencies are a strong risk factor in SLE, they are rare in lupus patients overall (7, 13, 14). In contrast, there is a large body of data on the association between low serum levels of functional C1q and clinical activities of SLE (7). Such low levels have generally been considered to be due to consumption of C1q molecules mediated by circulating or tissue-deposited ICs or to inactivation by anti-C1q autoantibodies found in patients with SLE (8). However, because SLE is a complex multigenic disease and because majorities of potent candidate susceptibility genes are polymorphic in nature (15), it may be reasonable to assume that certain C1q gene polymorphisms may cause down-regulation of C1q production and thus increase the susceptibility to SLE. In the present studies, we addressed this issue by investigating C1q gene polymorphisms, serum C1q levels, C1q-producing ability of cells, and their associations with SLE manifestations in a model of (NZB x NZW)F1 mice that spontaneously develop SLE under complex multigenic control (15). We propose that the New Zealand Black (NZB)-type polymorphism in the noncoding region of the C1q gene may be related to a limited degree of C1q production and thus may confer one genetic susceptibility to lupus nephritis.
|
Materials and Methods |
|---|
|
TopAbstractIntroductionMaterials and MethodsResultsDiscussionReferences |
|---|
BALB/c, NZB, New Zealand White (NZW), and (NZB x NZW)F1 mice, originally obtained from the Shizuoka Laboratory Animal Center (Shizuoka, Japan), were maintained in the animal facility of Juntendo University (Tokyo, Japan). Backcross mice were obtained by crossing female (NZB x NZW)F1 mice with male NZW mice. All these animals were housed in the same room and fed an identical diet. Because of female predominance of SLE, only female mice were used in the present study.
Measurement of proteinuria
The onset of renal disease was monitored by biweekly testing for
proteinuria, as described (16). Mice with proteinuria of
111 mg/100 ml or more in repeated tests were considered positive. For
quantitative trait loci (QTL) analysis, severity of renal disease was
scored from grade 0 to grade 6, according to the amount of urinary
albumin: 0, <37 mg/100 ml; 1, 
37 mg/100 ml; 2, 74 mg/ml; 3, 111
mg/100 ml; 4, 333 mg/100 ml; 5, 1000 mg/100 ml; 6, 3000
mg/100 ml.
Autoantibodies
Serum levels of autoantibodies to dsDNA and chromatin were determined by ELISA, using ELISA plates coated with dsDNA derived from the calf thymus and avian erythrocyte naive long chromatin, respectively. Binding activities were expressed in units, referring to a standard curve obtained by serial dilution of a standard serum pool from NZB mice >6 mo of age for IgM class Abs and (NZB x NZW)F1 mice >8 mo of age for IgG class Abs, respectively. Both contain 1000 unit activities per milliliter.
C1q production by peritoneal macrophages
Peritoneal exudate cells were obtained by washing the peritoneal cavity of the mice with 5% FCS RPMI 1640 medium. The cells were then washed with PBS (pH 7.4) and plated in 24-well flat-bottom plates (Nunc, Roskilde, Denmark) at 2 x 106 cells/well in 1 ml of RPMI 1640 medium supplemented with 10% FCS, 2 mM L-glutamine, 100 IU/ml penicillin, and 100 mg/ml streptomycin. After incubation for 2–3 h at 37°C in a humidified atmosphere containing 5% CO2, nonadherent cells were removed by aspirating off culture supernatants. Remaining adherent cells were cultured for 20 h in 0.5 ml/well culture medium in the presence of 2.5 µg/ml LPS (Difco, Detroit, MI), and the amount of C1q in the supernatant was determined in hemolytic assays.
Hemolytic assay for C1q activities
The activity of C1q in serum and in culture supernatants of peritoneal macrophages was measured. C1q-depleted human serum (C1q-D) was prepared by passing human serum through a human IgG-Sepharose 4B affinity column, as described (17). Ab-sensitized SRBCs (EA) were purchased from Nihon Biotest (Tokyo, Japan). A total of 100 µl of serum diluted to 1/2000 or culture supernatant diluted to 1/2 with GVB++ (ionic veronal buffered saline (pH 7.5) containing 1.5 x 10-4 M CaCl2, 5 x 10-4 M MgCl2, and 0.1% gelatin) was incubated with 5 µl of C1q-D and 100 µl of 1 x 108 EA/ml for 25 min at 37°C. After incubation, mixtures were placed on ice for 5 min and the reaction was halted by adding 0.4 ml of GBV containing 0.01 M EDTA. Remaining EA were removed by centrifugation at 4000 rpm for 5 min at 4°C, and the amount of hemoglobin released in the supernatant by hemolysis was measured spectrophotometrically at 412 nm.
Measurement of C1q protein levels by ELISA
Serum C1q protein levels were also determined using ELISA. Briefly, ELISA plates (Immulon 2; Dynatech Laboratories, Chantilly, VA) were coated overnight with 50 µl/well of 2 µg/ml rat anti-mouse C1q mAb (RMC7H8; Cedarlane Laboratories, Hornby, Ontario, Canada) in 0.1 M phosphate buffer (pH 9) at 4°C. After washing with washing medium (PBS with 0.05% Tween 20), nonspecific binding of proteins was blocked by incubating wells with 50% FCS in PBS at room temperature for 30 min. Wells were then washed with washing medium and incubated with 50 µl of 1/100 diluted serum samples in dilution buffer (washing medium supplemented with 1% BSA) at room temperature for 120 min. Next, the wells were incubated with 50 µl of 2 µg/ml biotinylated rat anti-mouse C1q mAb at room temperature for 60 min, followed by washing with washing medium and incubating with 50 µl of 1/10,000 diluted HRP (DAKO, Glostrup, Denmark) at room temperature for 30 min. After washing in washing medium, wells were developed with H2O2 and o-phenylendiamine. The reaction was stopped with 2.5 N H2SO4 and absorbance at 492 nm was measured on a microplate reader.
Genotyping for microsatellite markers
DNA was extracted from the mouse tail tissues. Genotyping for microsatellite markers was done using PCR. Microsatellite primers were purchased from Research Genetics (Huntsville, AL). PCR were run in a 96-well plate with 7.5 µl total volume containing 40 ng of genomic DNA. A three-temperature PCR protocol (94, 55, and 72°C) was conducted for 45 cycles in a Geneamp 9600 Thermal Cycler (PE Applied Biosystems, Foster City, CA). PCR products were diluted 2-fold with loading buffer consisting of xylene cyanol and bromophenol blue dyes in 50% glycerin and were run on 15% polyacrylamide gels. After electrophoresis, gels were stained with ethidium bromide.
H-2 typing
H-2 typing was done by flow cytometry analysis using peripheral lymphocytes stained with FITC-conjugated anti-IAu (Ia17) and anti-IAd (m52) mAbs.
Sequencing of C1q genes
Total RNA was isolated from spleens using ISOGEN (Nippon Gene, Tokyo, Japan). First-strand cDNA was synthesized using an oligo(dT) primer and coding sequences of C1qa, C1qb, and C1qc were analyzed using a PE Applied Biosystems 373A sequencer with Taq DNA polymerase and dye terminator. Sequencing of 5' and 3' flanking regions and introns of each of the a, b, and c genes was done using genomic DNA obtained from the mouse tail. Primers used were designed referring to the reported sequence (18). For sequencing of upstream region of the C1qa gene, we subcloned the 11.5-kb KpnI fragment including upstream region of the C1qa gene obtained from a BAC clone (Incyte Genomics, St. Louis, MO) into the KpnI site of pBluescript II SK+ (Stratagene, La Jolla, CA) and then sequenced using appropriate primers.
Southern blot hybridization
Genomic DNA was prepared from mouse liver tissue and 3 µg
of DNA was digested with BamHI or EcoRI (Life
Technologies, Gaithersburg, MD), according to the manufacturer’s
instructions. After digestion, DNA was run on 0.6% agarose gels,
transferred to nitrocellulose filters, and hybridized with radiolabeled
probes. Probes used were as follows: probe 1, the 0.118-kb
HincII-BstEII fragment of C1qa gene
upstream region; probe 2, the 0.18-kb fragment containing part of the
first exon of C1qa; probe 3, the 0.78-kb fragment containing
the intron/second exon boundary of C1qc (Fig. 1
A).
|
Total RNA was isolated from spleen cells and treated with DNase 1 (Life Technologies). Each C1qa, C1qb, and C1qc mRNA expression was measured by PCR, using the TaqMan method (19) and the ABI prism 7700 sequence detection system (PE Applied Biosystems), according to the manufacturer’s instructions. Primers used for amplification were as follows: for C1qa, forward 5'-TCTCAGCCATTCGGCAGAC-3' and reverse 5'-TGGTTGGTGAGGACCTTGTCA-3'; for C1qb, forward 5'-TCACCAACGCGAACGAGAA-3' and reverse 5'-AAGTAGTAGAGGCCAGGCACCTT-3'; and for C1qc, forward 5'-ACACATCGCATACGGCCAA-3' and reverse 5'-AACATGTGGTCGCAGAAGCTG-3'. To standardize amounts of RNA and to facilitate the calculation of relative amounts of each C1qa, C1qb, and C1qc mRNA expression, a reference control gene (GAPDH) was also amplified in a separate tube, according to the manufacturer’s instructions. The probes used were FAM-5'-CAATGACGCTTGGCAACGTGGTTATCT-3'-TAMRA for C1qa, FAM-5'-TATGAGCCACGCAACGGCAAGTTCA-3'-TAMRA for C1qb, and FAM-5'-TGCACCTGAACCTCAACCTTGCCA-3'-TAMRA for C1qc.
Statistics
Linkages of particular microsatellite loci with development of
proteinuria or low serum C1q levels were estimated using a computer
package program of MAPMAKER/EXP and MAPMAKER/QTL (20) to
identify chromosomal locations of QTL. The likelihood ratio statistic
(base-10 likelihood of the odds (LOD) score) of 3.3 was used as the
threshold for statistically significant linkage. For comparisons of C1q
and Ab levels, Student’s t test was used and p
values of <5% were considered to have a statistical significance.
|
Results |
|---|
|
TopAbstractIntroductionMaterials and MethodsResultsDiscussionReferences |
|---|
To determine whether there are any C1q gene polymorphisms, we first performed nucleotide sequence analyses of previously reported regions of the C1q gene, i.e., two exons and an intervening intron of each C1qa, C1qb, and C1qc gene and short segments of the 5' and 3' flanking regions of each C1q gene, including putative regulatory regions (18). Results showed no nucleotide substitutions in NZB, NZW, and BALB/c strains.
We then investigated polymorphisms in upstream regions of each
C1qa, C1qc, and C1qb gene by Southern
blot hybridization. DNA was digested with BamHI,
electrophoresed, and hybridized using probes with the C1qa
gene upstream region (probe 1), the first exon of C1qa gene
(probe 2), and the second exon of C1qc gene (probe 3) in
BALB/c, NZB, NZW, and (NZB x NZW)F1 mice
(Fig. 1
A). As shown in Fig. 1B, RFLP was only
detected with probe 1, but not with probe 2 and probe 3. The specific
band detected with the probe 1 in the NZB strain (9.7 kb) was longer
than that found in BALB/c and NZW strains (6.2 kb), suggesting two
possibilities. One is that the BamHI cutting site 7 kb
upstream from C1qa gene is missing in the NZB strain because
of sequence polymorphism. Another is that there is insertion of 3.5
kb between two BamHI cutting sites upstream from the
C1qa gene in the NZB strain (Fig. 1A). To
determine which is the case, DNA was also digested with
EcoRI, electrophoresed, and hybridized using probe 1.
Results showed that the band detected in the NZB strain (11.7 kb)
was longer than that found in BALB/c and NZW strains (8.2 kb) (Fig. 1C), thus indicating that the latter possibility is
feasible. However, exact sequence analysis for insertion polymorphism
has not been completed.
Linkage of C1q gene polymorphism to C1q production
To determine whether the noncoding region polymorphism of the NZB
C1q gene is indeed related to the level of C1q production,
we first compared serum C1q levels among BALB/c, NZB, NZW, and
(NZB x NZW)F1 mice aged 2 mo, using both
hemolytic assay and ELISA. Fig. 2A shows data of hemolytic
assay, indicating that NZB and (NZB x
NZW)F1 mice showed significantly lower serum C1q
activities than did BALB/c and NZW mice. These data were comparable
with data of serum C1q protein levels, as determined by ELISA, and mean
values of OD ± SE were 0.189 ± 0.014 in NZB, 0.202 ±
0.013 in (NZB x NZW)F1, 0.303 ± 0.015
in NZW, and 0.247 ± 0.009 in BALB/c mice. Values of NZB and
F1 mice were significantly lower than values of
NZW (p < 0.002 and p < 0.002,
respectively) and BALB/c mice (p < 0.003 and
p < 0.01, respectively). Because serum samples were
obtained from young mice before onset of disease, the observed low C1q
levels in NZB and (NZB x NZW)F1 mice were
unlikely to be due to C1q consumption by circulating and/or
tissue-deposited ICs. To confirm this issue, we then compared the
ability of cultured peritoneal macrophages obtained from 2-mo-old mice
to produce C1q in vitro. As shown in Fig. 2B, results were
comparable with those obtained by serum samples, indicating that C1q
activities in culture supernatants from NZB and (NZB x
NZW)F1 mice were significantly lower than those
from BALB/c and NZW mice. Table I shows
the result of quantitative real-time PCR assay demonstrating that each
C1qa, C1qb, and C1qc mRNA level was
significantly lower in NZB than in NZW mice, both at age 2 mo.
|
|
, the low serum C1q level was
significantly linked to D4 Mit70, a microsatellite closely
linked to the C1q allele, on NZB chromosome 4 (LOD, 3.6).
There was no linkage to the H-2 locus on chromosome 17,
suggesting that the low C1q level is not due to the result of disease,
because disorders in (NZB x NZW)F1 mice are
highly restricted to H-2d/z heterozygosity
(21, 22, 23).
|
To assess the effect of the polymorphic NZB C1q allele
on lupus nephritis, genome-wide QTL analysis for proteinuria was
performed, using the same backcross mice. Two major QTLs were detected;
one is located in the vicinity of the H-2 complex on
chromosome 17 in keeping with our earlier findings
(21, 22, 23) and the other is in the vicinity of NZB-type
D4 Mit70 on chromosome 4. LOD score was 17.5 for the former
and 5.2 for the latter, indicating a significant linkage (Fig. 4). Fig. 5A shows effects of
the H-2-linked and the
D4 Mit70-linked susceptibility alleles on the development of
lupus nephritis. The backcross progeny was separated into four groups,
according to combinations of H-2 and D4 Mit70
genotypes: group A, H-2d/z and NZB/NZW
D4 Mit70 genotypes; group B,
H-2d/z and NZW/NZW D4 Mit70;
group C, H-2z/z and NZB/NZW D4
Mit70; and group D, H-2z/z and NZW/NZW
D4 Mit70. The onset and cumulative incidence of proteinuria
were compared among these four groups. Compared with the result in
group D, the cumulative incidence of proteinuria was higher in either
group B or group C. It was to be noted that group A showed an earlier
onset and a higher incidence of proteinuria than either group B or
group C progeny, and that the onset and the cumulative incidence were
almost comparable to those found in (NZB x
NZW)F1 mice (Fig. 5B). Thus, it is
conceivable that the susceptibility to lupus nephritis in (NZB x
NZW)F1 mice is mainly determined by combined
effects of these H-2-linked and D4 Mit70-linked
genes.
|
|
Table II shows the effect of
H-2-linked and D4 Mit70-linked alleles on serum
levels of anti-dsDNA and anti-chromatin Abs in (NZB x
NZW)F1 x NZW backcross mice aged 8 mo. While the
levels of IgG class Abs to dsDNA and chromatin were significantly
associated with the H-2d/z heterozygosity,
there were no significant associations between the NZB-type D4
Mit70-linked allele and serum levels of both IgG and IgM
anti-dsDNA and anti-chromatin Abs; albeit the progeny
with NZB/NZW-type D4 Mit70 showed a tendency toward higher
serum levels of IgG anti-dsDNA Abs than were seen in the
NZW/NZW-type progeny in H-2d/z heterozygous
backcross mice.
|
|
Discussion |
|---|
|
TopAbstractIntroductionMaterials and MethodsResultsDiscussionReferences |
|---|
The functional C1q molecule consists of six pairs of A, B, and C
chains, each encoded by the C1qa, C1qb, and
C1qc gene, respectively (18, 24, 25). We found
no differences among NZB, NZW, and BALB/c strains in coding and intron
sequences of each C1qa, C1qb, and
C1qc, and in 5' flanking regions of C1qa and
C1qb, including reported putative promoter elements
(18). Thus, the decrease in C1q mRNA expression
levels in NZB mice appears to be due to undefined regulatory region
polymorphism. This polymorphism may be reflected by the observed RFLP
with C1qa upstream probe (probe 1), located between two
BamHI cutting sites in the C1qa upstream region.
There is an 3.5-kb insertion polymorphism in this region from NZB
mice. Studies to identify sequence polymorphism in this region are
ongoing in our laboratory. There was no RFLP in intervening sequences
between C1qa and C1qc genes and between
C1qc and C1qb genes; however, we could not
exclude the possibility that other regulatory elements are present in
these regions. Involvement of a regulatory region polymorphism of the
C1q gene in a certain type of familial C1q deficiency was
suggested by Petry (12), in which no sequence abnormality
was revealed in coding regions of all three C1qa,
C1qb, and C1qc genes and the intron-exon
boundaries.
Clearance of ICs in the circulation is a major function of early
complement components (8). Thus, decrease in C1q may
result in the impaired ability to clear ICs, leading to their tissue
deposition and subsequent tissue inflammation, especially in the
kidney. C1q proteins also play an important role in the clearance of
apoptotic bodies (8, 10, 26). Relevant was the finding
that there are increased numbers of glomerular apoptotic bodies in
C1q-deficient mice (10). In addition to the Ig-recognizing
subunit, C1q molecules have binding subunits for DNA (27)
and serum amyloid P component (SAP) (28, 29). SAP can bind
chromatin and solubilize chromatin of apoptotic cells
(30). C1q molecules bind to chromatin-SAP complexes and
mediate clearance of these macromolecular complexes from the
circulation. This mechanism may function to prevent vigorous autoimmune
responses to a variety of nuclear Ags. In support of this notion, both
C1q- and SAP-deficient mice develop a lupus-like disease with elevated
titers of antinuclear autoantibodies and progressive renal disease
(10, 30). In the present genetic studies in (NZB x
NW)F1 x NZW backcross mice, neither the number
of apoptotic bodies in renal glomerular lesions (data not shown) nor
autoantibody production against dsDNA and chromatin (Table II) was
significantly associated with C1q allele polymorphism.
Therefore, we speculate that the limited production of C1q in NZB and
(NZB x NZW)F1 mice may contribute to renal
disease mainly because of the impaired ability to clear ICs.
A single gene defect does not account for the pathogenesis of lupus nephritis (15). This notion is consistent with the renal disease model associated with C1q deficiency. Although C1q-deficient mice on a hybrid (129/Ola x C57BL/6) genetic background develop glomerulonephritis, no glomerulonephritis is detected in any of C1q-deficient mice on a pure 129/Ola background (10). Thus, unidentified C57BL/6 background gene(s) may be involved in this disorder. In the present studies, we found that a combination of both C1q-linked and H-2-linked NZB alleles contributes to the early onset and high incidence of severe renal disease in (NZB x NZW)F1 mice. Because the heterozygosity of H-2d from NZB and H-2z from NZW acts as a strong restriction element for production of pathogenic, high-affinity IgG autoantibodies (21, 22, 23), the H-2-linked NZB allele is thought to augment IC synthesis and the C1q-linked NZB allele may accelerate IC-type lupus nephritis through the effect of impaired IC clearance. In addition, because H-2d/z-congenic NZB mice with both H-2-linked and C1q-linked NZB genes do not develop severe renal disease as seen in (NZB x NZW)F1 mice (23), an additional unidentified gene(s) derived from the NZW strain is assumed to be involved.
Other investigators have mapped susceptibility alleles, nba-1 (31), Lbw2 (32), and Sle2 (33), for lupus nephritis on chromosome 4. The nba-1 and Lbw2 were shown to be located on the distal part of NZB chromosome 4 and thus may possibly be identical to the NZB-type C1q allele. Sle2 is located in the middle part of chromosome 4 of the NZM strain, a recombinant inbred strain generated from crosses between NZB and NZW strains (34). As Sle2 is the allele derived from the NZW strain, it differs from the NZB-type C1q allele in the present studies. In any instance, there may be several immunologically important, undefined genes clustering in the vicinity of C1q on the distal chromosome 4, and some such genes may also be involved in the susceptibility to lupus nephritis. The final goal to confirm the role of these genes in lupus susceptibility will largely depend on the generation of mutant mice with homologous recombination of these genes.
|
Acknowledgments |
|---|
|
Footnotes |
|---|
2 Address correspondence and reprint requests to Dr. Sachiko Hirose, Department of Pathology, Juntendo University School of Medicine, 2-1-1 Hongo, Bunkyo-ku, Tokyo 113-8421, Japan. E-mail address: sacchi{at}med.juntendo.ac.jp
3 Abbreviations used in this paper: SLE, systemic lupus erythematosus; IC, immune complex; LOD, likelihood of the odds; EA, Ab-sensitized SRBC; QTL, quantitative trait loci; SAP, serum amyloid P component.
Received for publication January 17, 2002. Accepted for publication May 17, 2002.
|
References |
|---|
|
TopAbstractIntroductionMaterials and MethodsResultsDiscussionReferences |
|---|
This article has been cited by other articles:
|
|
 |
|
  H A Martens, M W Zuurman, A H M de Lange, I M Nolte, G van der Steege, G J Navis, C G M Kallenberg, M A Seelen, and M Bijl Analysis of C1q polymorphisms suggests association with systemic lupus erythematosus, serum C1q and CH50 levels and disease severity Ann Rheum Dis, May 1, 2009; 68(5): 715 - 720. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 D. A. Fraser, M. Arora, S. S. Bohlson, E. Lozano, and A. J. Tenner Generation of Inhibitory NF{kappa}B Complexes and Phosphorylated cAMP Response Element-binding Protein Correlates with the Anti-inflammatory Activity of Complement Protein C1q in Human Monocytes J. Biol. Chem., March 9, 2007; 282(10): 7360 - 7367. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 W. Shiroiwa, K. Tsukamoto, M. Ohtsuji, Q. Lin, A. Ida, S. Kodera, N. Ohtsuji, K. Nakamura, H. Tsurui, K. Kinoshita, et al. IL-4R{alpha} polymorphism in regulation of IL-4 synthesis by T cells: implication in susceptibility to a subset of murine lupus Int. Immunol., February 1, 2007; 19(2): 175 - 183. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 D. A. Fraser, S. S. Bohlson, N. Jasinskiene, N. Rawal, G. Palmarini, S. Ruiz, R. Rochford, and A. J. Tenner C1q and MBL, components of the innate immune system, influence monocyte cytokine expression J. Leukoc. Biol., July 1, 2006; 80(1): 107 - 116. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 M. K. Haraldsson, N. G. dela Paz, J. G. Kuan, G. S. Gilkeson, A. N. Theofilopoulos, and D. H. Kono Autoimmune Alterations Induced by the New Zealand Black Lbw2 Locus in BWF1 Mice J. Immunol., April 15, 2005; 174(8): 5065 - 5073. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 N. Li, K. Nakamura, Y. Jiang, H. Tsurui, S. Matsuoka, M. Abe, M. Ohtsuji, H. Nishimura, K. Kato, T. Kawai, et al. Gain-of-function polymorphism in mouse and human Ltk: implications for the pathogenesis of systemic lupus erythematosus Hum. Mol. Genet., January 15, 2004; 13(2): 171 - 179. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
K. Nakamura, Y. Xiu, M. Ohtsuji, G. Sugita, M. Abe, N. Ohtsuji, Y. Hamano, Y. Jiang, N. Takahashi, T. Shirai, et al. Genetic dissection of anxiety in autoimmune disease Hum. Mol. Genet., May 15, 2003; 12(10): 1079 - 1086. [Abstract] [Full Text] [PDF]
|
|
| |||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
, and probes used for Southern blot
analysis are shown below. Restriction sites previously
reported (
