| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
|
|
|
|||||||
|
|||||||||
2 Gene Underlies the IL-12 Unresponsiveness of Lps-Defective C57BL/10ScCr Mice1
*
The Scripps Research Institute, La Jolla, CA 92037; and
Max-Planck-Institut für Immunbiologie, Freiburg, Germany
 |
Abstract |
|---|
 Top Abstract IntroductionMaterials and MethodsResultsDiscussionReferences |
|---|
responses to different microorganisms. By
positional cloning methods, we show here that this second defect of Cr
mice is due to a mutation in a single gene located on mouse chromosome
6, in close proximity to the Ig
locus. The gene is
IL-12R
2. Cr mice carry a point mutation creating a
stop codon that is predicted to cause premature termination of the
translated IL-12R2 after a lysine residue at position 777. The
truncated 2 chain can still form a heterodimeric IL-12R that allows
phosphorylation of Janus kinase 2, but, unlike the wild-type IL-12R,
can no longer mediate phosphorylation of STAT4. Because the
phosphorylation of STAT4 is a prerequisite for the IL-12-mediated
induction of IFN-, its absence in Cr mice is responsible for their
defective IFN- response to microorganisms. |
Introduction |
|---|
|
TopAbstractIntroductionMaterials and MethodsResultsDiscussionReferences |
|---|
Three strains of LPS-resistant mice have been described. These are the C3H/HeJ (3), C57BL/10ScCr (Cr)4 (4), and its progenitor C57BL/10ScNCr (ScN) (5). In C3H/HeJ mice, the mutation abolishing LPS responsiveness is associated with the substitution of an evolutionarily conserved proline for histidine at position 712 of the Toll-like receptor (Tlr)4 polypeptide chain (6). In Cr mice, LPS unresponsiveness is due to a null mutation of Tlr4 corresponding to a 74-kb genomic deletion encompassing the locus (7).
Although Lps has now been identified and the corresponding
defects in C3H/HeJ and Cr mice elucidated, an important question
related to these two Tlr4 mutated strains has remained open.
This question has centered on fundamental differences in the responses
witnessed in these animals following treatment with Gram-negative and
Gram-positive bacteria, and two protozoa tested thus far
(Plasmodium chabaudi chabaudi, Leishmania
major) (1, 8, 9). Thus, Cr mice, but not
LPS-responsive congenic C57BL/10ScSn (Sn) mice, are incapable of
producing IFN- when inoculated with these microorganisms. By
contrast, both C3H/HeJ mice and the congenic responder strain C3H/HeN
produced normal quantities of IFN- in response to such challenges
(reviewed in Ref. 10). Because IFN- mediates the
sensitization to LPS that develops during infection, C3H/HeJ mice
pretreated with live or killed microorganisms become partially
susceptible to LPS, whereas Cr mice retain profound LPS resistance
(1, 10, 11). Thus the LPS response defect in the Cr mouse
is more severe than that observed in the C3H/HeJ strain (reviewed in
Ref. 10). It was considered possible that the mutant
receptor of C3H/HeJ mice might retain some signaling potential, which
under the influence of IFN- conferred partial responsiveness,
whereas in Cr the receptor did not exist, and therefore, signaling
would be absent under all circumstances. However, further studies gave
cause to reject this hypothesis (2). ScN, the progenitor
strain from which Cr arose, was found to have a deletion of the
Tlr4 locus identical with that observed in Cr. Yet ScN
animals, although resistant to LPS, showed normal IFN- production
when infected and like C3H/HeJ mice became thereby partially sensitive
to LPS. It seemed, then, that a second mutational event must have
occurred in the Cr strain following its separation from the ScN strain.
Confirmation for this was obtained when the defect in IFN-
production of Cr mice was found to be due to a failure of these mice to
respond to IL-12, whereas in ScN mice IL-12 responses were normal
(2).
In principle, the defect of IL-12 responsiveness could be related to
any component essential for IL-12 signaling. However, some of these
components (e.g., Janus protein tyrosine kinases (Jak) Tyk 2
and Jak 2, or the transcription factors STAT1 and STAT3) are
used for signaling also by other cytokines. Because the responses to
several cytokines including TNF-
(12), IFN-
(13), and IFN- (11) were shown to be
intact in Cr mice, we assumed that a component more specific for IL-12
effects, such as receptor subunits 1, 2, or STAT4
(14, 15, 16, 17), or an as yet unknown essential component, must
be affected. We now show that the defective response to IL-12 of Cr
mice is controlled by a single locus located on mouse chromosome 6
(unlinked to Tlr4). This locus is identical with the
IL-12R2 gene, and in the Cr mouse it carries a mutation
that leads to the production of a defective IL-12R2 chain and thus
to a malfunction of the Il-12R. Thus, the complex immune phenotype of
Cr mice results from the co-inheritance of two mutations, one in
Tlr4 and the other in IL-12R2.
|
Materials and Methods |
|---|
|
TopAbstractIntroductionMaterials and MethodsResultsDiscussionReferences |
|---|
Cr, Sn, ScN, 129 SvPas, and BALB/c mice were obtained from the breeding stock of the Max-Planck-Institut für Immunbiologie.
Materials
Listeria monocytogenes was grown and killed as
described previously (18). For use the bacteria were
suspended in pyrogen-free PBS, pH 7.2. Murine rIL-12 was purchased from
PharMingen (San Diego, CA). Murine rIFN- was provided by G. R.
Adolph (Bender & Co., Vienna, Austria). Con A was purchased from
Pharmacia (Freiburg, Germany).
Preparation and stimulation of splenocytes
Splenocyte suspensions were prepared from spleens of 6- to
10-wk-old mice by pressing spleens through a wire grid. For studies on
IFN- induction, cells from individual animals were suspended in
serum-free DMEM at 107 cells/ml and placed
(2 x 106 cells/well) in 96-well plates
(Nunc, Roskilde, Denmark). After culturing in the presence or absence
of stimulating agents (rIL-12, 1.25 ng; L. monocytogenes, 2
µg) in 10 µl/well at 37°C in a humidified atmosphere containing
8% CO2 for 24 h, the culture supernatants
were stored in aliquots at -80°C until determination of IFN-. For
immunoblotting analysis, pooled cells from 3 to 6 animals were
suspended in RPMI 1640 medium supplemented with 10% FCS, adjusted to a
concentration of 2 x 106 cells/ml, and
cultured in the presence of 5 µg/ml Con A at 37°C in a humidified
atmosphere containing 5% CO2. After 3 days the
Con A-activated splenocytes were washed free of serum and cultured for
3 h in serum-free RPMI 1640 in the absence of Con A
(starvation step). Thereafter, cells were centrifuged, resuspended at
5 x 107 cells/0.5 ml medium, and stimulated
at 37°C with murine rIL-12 (50 ng/ml, 15 min) or 50 µM
pervanadate-H2O2 (5 min) as
described (19) or left untreated (control).
Determination of IFN-
IFN- in supernatants of splenocytes was estimated by a
previously described ELISA (20).
Immunoprecipitation and immunoblotting
Cells were lysed in Brij 97 (Sigma-Aldrich, Taufkirchen, Germany) as described (21). STAT4 and Jak2 proteins were immunoprecipitated using anti-STAT4 mAb (C-20; Santa Cruz Biotechnology, Santa Cruz, CA) and anti-Jak2 antisera (Upstate Biotechnology, Lake Placid, NY), respectively, conjugated to protein A-coupled Sepharose beads (CL4B; Pharmacia Biotech, Uppsala, Sweden). The immunoprecipitates were resolved by 10% SDS-PAGE and transferred to a nitrocellulose membrane. For detection of tyrosine-phosphorylated STAT4 and Jak2, membranes were blocked in TBS containing 2% BSA and sequentially incubated with an anti-phosphotyrosine mAb (4G-10; Upstate Biotechnology) and HRP-conjugated rabbit anti-mouse Ab (DAKO, Glostrup, Denmark). After stripping with a buffer containing 0.062 M Tris pH 6.8, 0.1 M 2-ME, and 2% SDS, blots were incubated sequentially with anti-Jak2 or anti-STAT-4 mAb (both purchased from Santa Cruz Biotechnology) and HRP-conjugated swine anti-rabbit Ab (DAKO). The blots were developed by ECL (Amersham Little Chalfont, U.K.).
Linkage mapping, contig building, and gene identification
Single-strand-length polymorphism analysis was performed
according to standard procedures (22) using high m.w.
genomic DNA (23). MAP MAKER (24) was used to
construct a genetic map. A total of 150 D6 Mit markers surrounding
Ifnm were tested on the polymorphism between Cr and 129
strain of mice. Contigs of bacterial artificial chromosome (BAC) (1)
clones at the distal end of the Ig locus were established
as described (25, 26). Selected BACs were subjected to a
shotgun sequencing approach; the obtained sequences were compared with
the GenBank database entries, and selected regions were fully sequenced
by closing gaps with primer walking strategies.
IL-12R1 and IL-12R2 sequence analysis
Standard molecular biological procedures were used to determine
the cDNA and genomic sequence of IL-12R2 (accession no. U64199) for
Cr and ScN strains using PCR amplification. cDNA was derived by reverse
transcription of total splenic RNA. The primers used for the PCR
(positions 104–122 and 2769–2787) were situated adjacent to the start
and stop codons (positions 139 and 2761, respectively). Additional
internal primers were used to obtain the complete sequence. To
discriminate between wild-type and Cr alleles at IL-12R2,
specific PCR primers (5'-ACCACATGATCCCAGTTGTCAGAC-3' and
5'-TACGTTGGCTTTCTAGTATCAAGC-3') flanking the region containing the
C to G transversion resulting in premature termination of translated
protein were used to amplify genomic DNA from N2 mice. PCR products
were then directly sequenced. The cDNA sequence for IL-12R1
(accession no. U23922) in Cr and ScN strains was also compared from
position 40–2565. Cr and ScN sequences were identical but showed five
silent and three nonsilent changes in the coding region, and two
changes in the 3' untranslated region, when compared with the
published BALB/c sequence (77: C to G; 542: G to C; 607: G to T; 683: T
to C; 967: A to G; 1297: A to G; 1663: G to C; 2330: T to G; 2440: C to
G; open reading frame = 59–2275).
|
Results |
|---|
|
TopAbstractIntroductionMaterials and MethodsResultsDiscussionReferences |
|---|
To investigate whether the phenotypic variation is due to
different kinds of Tlr4 mutations, genetic linkage analysis
was performed. F1 animals produced by an outcross
of Cr animals to BALB/c, 129/SvPas, and Sn strains exhibited slightly
lower IL-12 responses than the respective wild-type parents, indicating
that the mutation is recessive or, at most, weakly codominant (data not
shown). To confirm that a single locus in Cr mice was responsible for
the IL-12 response defect, we backcrossed F1
(Cr x 129/SvPas) mice to the defective Cr parent. The first 23
mice from this backcross together with parental strains were analyzed
for the production of IFN- in response to IL-12. The results of this
analysis are shown in Fig. 1
A.
The approximate 1:1 distribution of phenotypes evident in
N2 animals derived from this backcross suggested
that mutation of a single genetic locus (provisionally termed
Ifnm) causes the defective response to IL-12. A concomitant
evaluation of the IL-12 responsiveness and the Tlr4 genotype
for each individual N2 animal revealed that the
two defects segregate independently (Fig. 1B), consistent
with the hypothesis that the two mutations of Cr mice are unlinked to
each other. To investigate the molecular nature of the Ifnm
locus, a positional cloning strategy was used.
|
For an initial genome-wide screening, a group of 23 mice was
examined with respect to a panel of 40 polymorphic simple sequence
repeats distributed over all of the autosomes (data not shown). The
Ifnm locus was initially mapped to mid-chromosome 6 of the
mouse, and was confined to the region flanked by markers D6 Mit55 and
D6 Mit188 (logarithm of score = 14.3). No other significant
associations were detected in this linkage screen, confirming that one
and only one mutation confers IL-12 resistance. An extended meiotic
mapping panel was used to further confine the gene with respect to
markers interposed between D6 Mit118 and D6 Mit188 (Fig. 2). Marker D6 Mit118 was used for further
analysis of recombinants because it was found to be more proximal to
Ifnm than D6 Mit55. Based on 140 meioses, the gene was
confined to an interval 4 cM in length, delimited by markers D6 Mit123
and D6 Mit188. In all, 19 D6 Mit markers were examined for polymorphism
in this region, and eight were found to distinguish Cr from the
129/SvPas strain. The genetic map in the region established the order,
shown in Fig. 3A. We achieved
higher resolution for the centromeric part of the region than that
presented in publicly available databases
(http://www.informatics.jax.org and European Collaborative
interspecific backcross) and ordered new markers (D6 Mit317, D6 Mit356)
within the area surrounding the Ifnm locus. The D6 Mit356
marker colocalized with Ifnm in the entire series of mice.
At the same time, we were not able to narrow the interval between
Ifnm and D6 Mit188, which contained six crossovers.
|
|
2 gene
The Ifnm locus is closely linked to the murine
Ig locus (Fig. 3
B), for which detailed
physical maps had previously been generated across a region several
megabases in length (25, 26). Here we have extended these
maps into the region upstream of Ig and localized several genes
(Fig. 3C). Among the genes identified in this region, the
IL-12R2 appeared to be the most likely candidate for the
Ifnm locus, because together with the IL-12R1 subunit,
its product forms the high affinity IL-12R. The human
IL-12R2 gene has been assigned to chromosome 1, band 31.2
(27), whereas the human Ig locus resides on
chromosome 2; two other genes flanking IL-12R2 gene in
the mouse, Cgi55 and Trop2, are also located on
human chromosome 1. Thus, the region between Trop2 and the
most distal V gene (IgV24f, Fig. 3C) on
mouse chromosome 6 contains the junction of two syntenic regions found
on human chromosomes 1 and 2.
IL-12R2 cDNAs from Cr and C57BL/10ScN (ScN) mice were amplified and
their sequences were compared. A single mutation (substitution of a C
for a G at position 2472) within the cytoplasmic domain of the molecule
was observed, creating a stop codon that is predicted to cause
premature termination of the translated protein after a lysine residue
at position 777, and to yield a truncated 2 chain that would lack
the C-terminal 97 aa (Fig. 4) of the
cytoplasmic domain. The mutation in IL-12R2 was confirmed
by sequencing the corresponding region of genomic DNA (data not shown).
In addition, IL-12R1 cDNAs from Cr and C57BL/10ScN (ScN) mice were
amplified and sequenced. They were found to be identical but were
polymorphic to the published BALB/c sequence.
|
2 gene we genotyped the first group of backcross
mice (Fig. 1) and found that the allele distribution in these animals
conforms to expectation; mice unresponsive to IL-12 are homozygous for
the nonsense mutation in the IL-12R2 gene, whereas those
animals that respond to IL-12 have both Cr and wild-type alleles (data
not shown). As was shown for the human IL-12R2 chain
(28), the proximal and distal parts of the cytoplasmic
domain contain binding sites for Jak2 and for the transcription factor
STAT4, respectively.
A mutation in the IL-12R2 gene disturbs signaling
In an attempt to show the functional significance of the
IL-12R2 mutation, we examined the phosphorylation of
endogenous STAT4 and Jak2 in splenocytes obtained from Cr and ScN mice.
STAT4 is a transcriptional activator (29) that was found
to be essential in IL-12 signaling in the mouse (16, 17).
Direct interaction of the Src homology 2 domain of the STAT4 with a
phosphotyrosine residue in the IL-12R has been proposed to be required
for subsequent STAT4 phosphorylation in human cells (30).
Using peptides from the cytoplasmic domain of IL-12R2, it was shown
that a small region surrounding pTyr800 is critically involved in
binding STAT4. If this result were to be applied to the mouse, then the
removal of 97 aa from the cytoplasmic domain of IL-12R2 should
abolish STAT4 phosphorylation (Fig. 4). As shown in Fig. 5A, stimulation of spleen
cells with IL-12 causes phosphorylation of STAT4 in cells from ScN mice
but not in cells from Cr mice. This result is evidence that the
STAT4-binding site in the truncated IL-12R2 subunit is absent. In
this respect, Cr is similar to the recently described
IL-12R2-/- mouse (15), in which
no phosphorylation of STAT4 in response to IL-12 takes place due to a
complete absence of 2. Next, we examined the interaction of
IL-12R2 with Jak2, which is implicated in the IL-12 transduction
pathway by association with the membrane-proximal region of the
cytoplasmic domain of IL-12R2. The results (Fig. 5B) show
that the deletion in the C-terminal domain of the IL-12R2 chain does
not affect the binding and subsequent phosphorylation of Jak2. Two
different Jaks are known to associate with the two different subunits
of the IL-12R. Jak2, as mentioned above, associates with the IL-12R2
subunit and Tyk2 associates with the IL-12R1 subunit
(31). The activation of these kinases occurs by
transphosphorylation (32). Therefore, the presence of
phosphorylated Jak2 in IL-12-stimulated Cr splenocytes also indicates
the presence of phosphorylated Tyk2. In this respect, Cr mice differ
from IL-12R1-/- and
IL-12R2-/- mice, which are expected to be
incapable of phosphorylating Tyk2 or Jak2 in response to IL-12 (see
also Fig. 5 for IL-12R1-/-).
|
|
Discussion |
|---|
|
TopAbstractIntroductionMaterials and MethodsResultsDiscussionReferences |
|---|
response to microorganisms. Using positional cloning
procedures, the defective gene in question was located on chromosome 6
and is shown to be identical with IL-12R2. The defective
gene carries a point mutation resulting in a IL-12R2 subunit that
lacks the 97 carboxyl-terminal amino acids. Thus, the IL-12R of Cr mice
consists of a normal 1 and a truncated 2 chain. As a result,
activation of STAT4 by IL-12 and subsequent induction of IFN- are
absent. This result documents that, as is the case in humans
(30), in mice the binding site for STAT4 in the IL-12R is
also located in the distal part of the cytoplasmic domain of its 2
chain. Furthermore, the loss of IL-12 responsiveness in Cr mice is in
agreement with current knowledge that both subunits are necessary
for an IL-12 functional receptor. As shown in mice, the targeted
disruption of IL-12R1 or IL-12R2 abolishes
the IFN- response to IL-12 (14, 15). In this respect,
IL-12R1-/- and
IL-12R2-/- mice are phenotypically identical
with Cr mice. This is understandable because the inability to activate
STAT4, which is essential in the IL-12-induced IFN- response
(16, 17), is a common feature of all three strains of
mice. However, unlike the two knockout mice, in which the IL-12
function is completely lost, the truncated IL-12R of Cr mice still
allows binding and activation of the Jaks Jak2 and Tyk2 after IL-12
stimulation.
It was recently reported that IL-12R2-/-
mice exhibit a deficient type 1 Th1 response (as determined by IFN-
production) when stimulated with the T cell mitogen Con A or soluble
anti-CD3 (15). In contrast, naive spleen cells of
adult Cr mice exhibit normal or only slightly diminished IFN-
(2, 8, 13) and normal IL-2 (M. A. Freudenberg, unpublished
data) responses when stimulated with the above agents.
Furthermore, Cr splenocytes exhibit normal IL-2 responses when
stimulated with heat-killed bacteria (M. A. Freudenberg, unpublished
data). Thus, there seems to be a difference between Cr and the
IL-12R2-/- mice in their ability to mount
Th1 responses to T cell mitogens. This may suggest that the modified
IL-12R of Cr mice still retains a residual signaling potential
supporting the normal development of Th1 cells and their responses to
mitogens.
IL-12 is an important factor of the mammalian immune system, being a T
and NK cell activator, an IFN- inducer, and an initiator of type 1
Th1 cell development (reviewed in Ref. 33). TLR4 protein
is one of the primary sensors of the innate immune system, responsible
for detecting the LPS of Gram-negative bacteria. IL-12 and LPS
stimulate very different signaling pathways, and overall, the combined
IL-12R2 and Tlr4 defects in Cr mice are
expected to bring about several malfunctions of the innate and specific
immune systems. Nevertheless, Cr mice exhibit normal pre- and postnatal
development. They differ from wild-type Sn and from ScN mice only by a
slightly enhanced mortality of pups during the first few days after
birth. Otherwise, they exhibit a normal life span (2–3 years), at
least under specific pathogen-free or conventional conditions in the
animal facilities of the Max-Planck-Institute. Quantitative analysis
(FACS) of CD14+ macrophages,
CD45R+ B cells, CD3+,
CD4+, and CD8+ T cells, and
NK1.1+ cells present in the spleen of Cr and
IL-12 responder Sn mice revealed no significant differences between the
two strains (data not shown). These data show that IL-12 and Tlr4 are
not required for the normal development of T, B, and NK cells and are
in agreement with previous reports (14, 15, 34).
The availability of Cr, as well as the closely related Sn and ScN mice
opens interesting possibilities for studying the mechanisms involved in
the innate immune defense against pathogens on a defined genetic
background. In the past, Cr and Sn mice were successfully used to show
that IFN- is a cofactor of IFN- production and that endogenous
IFN- participates in the induction of IFN- by Gram-negative
bacteria (13).
A recent study described the exaggerated susceptibility of Cr mice to
infection by respiratory syncytial virus as a result of mutation of
Tlr4 (35). This interpretation needs to be
re-examined in light of the fact that Cr mice are incapable of
responding to IL-12. IL-12-associated defects seem to play a role also
in the development of allergy. Occurrence of atopic individuals,
heterozygous for defective IL-12R2, including those
exhibiting truncated IL-12R2 proteins, has been reported
(36). Moreover, insofar as the complex immune phenotype of
these mice was explained by sequential positional cloning approaches,
there is reason to hope that other complex immune phenotypes (e.g.,
murine systemic lupus erythematosus or type I diabetes) might
similarly be resolved through sequential approaches aimed at carefully
selected phenotypic components of the disorder in question.
|
Acknowledgments |
|---|
|
Footnotes |
|---|
2 A.P. and T.M. contributed equally to this work.
3 Address correspondence and reprint requests to Dr. Marina A. Freudenberg, Max-Planck-Institut für Immunbiologie, Stübeweg 51, D-79108 Freiburg, Germany. E-mail address: freudenberg{at}immunbio.mpg.de
4 Abbreviations used in this paper: Cr, C57BL/10ScCr; ScN, C57BL/10ScNCr; Jak, Janus protein tyrosine kinase; Sn, C57BL/10ScSn; Tlr, Toll-like receptor; BAC, bacterial artificial chromosome.
Received for publication April 19, 2001. Accepted for publication June 1, 2001.
|
References |
|---|
|
TopAbstractIntroductionMaterials and MethodsResultsDiscussionReferences |
|---|
interferon production in endotoxin-responder and -nonresponder mice during infection. Infect. Immun. 59:3484. and tumor necrosis factor in mice during Salmonella typhimurium infection. Pathobiology 59:194.[Medline]
interferon mediates Propionibacterium acnes-induced hypersensitivity to lipopolysaccharide in mice. Infect. Immun. 60:1994., a cofactor in the interferon production induced by Gram-negative bacteria in mice. J. Exp. Med. 181:953.1
chain (IL-12R1)-deficient mice: IL-12R1 is an essential component
of the functional mouse IL-12 receptor. J. Immuno1.
59:1658.
interferon in mice is a function of the lipopolysaccharide component. Infect. Immun. 68:1600. during infection of mice with Plasmodium chabaudi chabaudi. Immunobiology 179:353.[Medline]
locus. Eur. J. Immunol. 29:2072.[Medline]
light chain locus. Immunogenetics 45:180.[Medline]
1 and 2 chains, to human chromosome 19 band p13.1 and chromosome 1 band p31.2, respectively, by in situ hybridization. Cytogenet. Cell Genet. 77:257.[Medline]
2 subunit and Jak2 tyrosine kinase: Jak2 associates with cytoplasmic membrane-proximal region of interleukin-12 receptor 2 via amino-terminus. Biochem. Biophys. Res. Commun. 257:400.[Medline]
1 and 2 and JAK kinases. J. Biol. Chem. 272:6073. production and type 1 cytokine responses. Immunity 4:471.[Medline]
2 chain gene in atopic subjects. Biochem. Biophys. Res. Commun. 266:551.[Medline]This article has been cited by other articles:
|
|
 |
|
  S. F. Martin, J. C. Dudda, E. Bachtanian, A. Lembo, S. Liller, C. Durr, M. M. Heimesaat, S. Bereswill, G. Fejer, R. Vassileva, et al. Toll-like receptor and IL-12 signaling control susceptibility to contact hypersensitivity J. Exp. Med., September 1, 2008; 205(9): 2151 - 2162. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 A. Goldberg, M. Parolini, B. Y. Chin, E. Czismadia, L. E. Otterbein, F. H. Bach, and H. Wang Toll-like receptor 4 suppression leads to islet allograft survival FASEB J, September 1, 2007; 21(11): 2840 - 2848. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 M M Heimesaat, A Fischer, H-K Jahn, J Niebergall, M Freudenberg, M Blaut, O Liesenfeld, R R Schumann, U B Gobel, and S Bereswill Exacerbation of murine ileitis by Toll-like receptor 4 mediated sensing of lipopolysaccharide from commensal Escherichia coli Gut, July 1, 2007; 56(7): 941 - 948. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 S. Spiller, S. Dreher, G. Meng, A. Grabiec, W. Thomas, T. Hartung, K. Pfeffer, H. Hochrein, H. Brade, W. Bessler, et al. Cellular Recognition of Trimyristoylated Peptide or Enterobacterial Lipopolysaccharide via Both TLR2 and TLR4 J. Biol. Chem., May 4, 2007; 282(18): 13190 - 13198. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 M. Jayachandran, G. J. Brunn, K. Karnicki, R. S. Miller, W. G. Owen, and V. M. Miller In vivo effects of lipopolysaccharide and TLR4 on platelet production and activity: implications for thrombotic risk J Appl Physiol, January 1, 2007; 102(1): 429 - 433. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 B. Liu, Y. Yang, J. Dai, R. Medzhitov, M. A. Freudenberg, P. L. Zhang, and Z. Li TLR4 Up-Regulation at Protein or Gene Level Is Pathogenic for Lupus-Like Autoimmune Disease J. Immunol., November 15, 2006; 177(10): 6880 - 6888. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 J. S. Lee, C. W. Frevert, G. Matute-Bello, M. M. Wurfel, V. A. Wong, S.-M. Lin, J. Ruzinski, S. Mongovin, R. B. Goodman, and T. R. Martin TLR-4 pathway mediates the inflammatory response but not bacterial elimination in E. coli pneumonia Am J Physiol Lung Cell Mol Physiol, November 1, 2005; 289(5): L731 - L738. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
A.-C. Oliveira, J. R. Peixoto, L. B. de Arruda, M. A. Campos, R. T. Gazzinelli, D. T. Golenbock, S. Akira, J. O. Previato, L. Mendonca-Previato, A. Nobrega, et al. Expression of Functional TLR4 Confers Proinflammatory Responsiveness to Trypanosoma cruzi Glycoinositolphospholipids and Higher Resistance to Infection with T. cruzi J. Immunol., November 1, 2004; 173(9): 5688 - 5696. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 S. Antoniazi, H. P. Price, P. Kropf, M. A. Freudenberg, C. Galanos, D. F. Smith, and I. Muller Chemokine Gene Expression in Toll-Like Receptor-Competent and -Deficient Mice Infected with Leishmania major Infect. Immun., September 1, 2004; 72(9): 5168 - 5174. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 P. Kropf, N. Freudenberg, C. Kalis, M. Modolell, S. Herath, C. Galanos, M. Freudenberg, and I. Muller Infection of C57BL/10ScCr and C57BL/10ScNCr mice with Leishmania major reveals a role for Toll-like receptor 4 in the control of parasite replication J. Leukoc. Biol., July 1, 2004; 76(1): 48 - 57. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
P. Kropf, M. A. Freudenberg, M. Modolell, H. P. Price, S. Herath, S. Antoniazi, C. Galanos, D. F. Smith, and I. Muller Toll-Like Receptor 4 Contributes to Efficient Control of Infection with the Protozoan Parasite Leishmania major Infect. Immun., April 1, 2004; 72(4): 1920 - 1928. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 J.-i. Oyama, C. Blais Jr, X. Liu, M. Pu, L. Kobzik, R. A. Kelly, and T. Bourcier Reduced Myocardial Ischemia-Reperfusion Injury in Toll-Like Receptor 4-Deficient Mice Circulation, February 17, 2004; 109(6): 784 - 789. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 M. A. Freudenberg, C. Kalis, Y. Chvatchko, T. Merlin, M. Gumenscheimer, and C. Galanos Role of interferons in LPS hypersensitivity Innate Immunity, October 1, 2003; 9(5): 308 - 312. [Abstract] [PDF]
|
|
|
|
|
|
F. Bihl, L. Salez, M. Beaubier, D. Torres, L. Lariviere, L. Laroche, A. Benedetto, D. Martel, J.-M. Lapointe, B. Ryffel, et al. Overexpression of Toll-Like Receptor 4 Amplifies the Host Response to Lipopolysaccharide and Provides a Survival Advantage in Transgenic Mice J. Immunol., June 15, 2003; 170(12): 6141 - 6150. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
B. Beutler Review paper: LPS in microbial pathogenesis: promise and fulfilment Innate Immunity, October 1, 2002; 8(5): 329 - 335. [Abstract] [PDF]
|
|
|
|
|
|
M. Gumenscheimer, I. Mitov, C. Galanos, and M. A. Freudenberg Beneficial or Deleterious Effects of a Preexisting Hypersensitivity to Bacterial Components on the Course and Outcome of Infection Infect. Immun., October 1, 2002; 70(10): 5596 - 5603. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 J. A. Thomas, M. F. Tsen, D. J. White, and J. W. Horton TLR4 inactivation and rBPI21 block burn-induced myocardial contractile dysfunction Am J Physiol Heart Circ Physiol, October 1, 2002; 283(4): H1645 - H1655. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
M. A. Freudenberg, T. Merlin, C. Kalis, Y. Chvatchko, H. Stubig, and C. Galanos Cutting Edge: A Murine, IL-12-Independent Pathway of IFN-{gamma} Induction by Gram-Negative Bacteria Based on STAT4 Activation by Type I IFN and IL-18 Signaling J. Immunol., August 15, 2002; 169(4): 1665 - 1668. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
G. B. Johnson, G. J. Brunn, Y. Kodaira, and J. L. Platt Receptor-Mediated Monitoring of Tissue Well-Being Via Detection of Soluble Heparan Sulfate by Toll-Like Receptor 4 J. Immunol., May 15, 2002; 168(10): 5233 - 5239. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 M. A. Farmer, J. P. Sundberg, I. J. Bristol, G. A. Churchill, R. Li, C. O. Elson, and E. H. Leiter A major quantitative trait locus on chromosome 3 controls colitis severity in IL-10-deficient mice PNAS, November 9, 2001; (2001) 241258698. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
M. A. Farmer, J. P. Sundberg, I. J. Bristol, G. A. Churchill, R. Li, C. O. Elson, and E. H. Leiter A major quantitative trait locus on chromosome 3 controls colitis severity in IL-10-deficient mice PNAS, November 20, 2001; 98(24): 13820 - 13825. [Abstract] [Full Text] [PDF]
|
|
| |||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
2 analysis of allele distribution of 23 backcross mice
(p value is 0.98; 
, Homozygote; 
, heterozygote. The number of
offspring inheriting each type of chromosome is listed at the bottom of
each column. R, Distance in cM. SE values are listed to the right of
the figure.
,
presence and absence (x) of these markers as determined by PCR.
90 and 116 kDa, respectively).