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*
Department of Dermatology, Keio University School of Medicine, Tokyo, Japan; and
Department of Internal Medicine, Faculty of Veterinary Medicine, Tokyo University of Agriculture and Technology, Tokyo, Japan
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Abstract |
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 Top Abstract IntroductionMaterials and MethodsResultsDiscussionReferences |
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Introduction |
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TopAbstractIntroductionMaterials and MethodsResultsDiscussionReferences |
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Characterizing the Dsg binding sites of the pathogenic pemphigus autoantibodies is an essential step in understanding the pathophysiology of blister formation in pemphigus, as well as the basic molecular mechanism of Dsg-mediated cell-cell adhesion. This characterization is hindered by the fact that binding of autoantibodies to Dsgs is dependent not only on amino acid sequence, but also on molecular conformation (9, 13, 14, 15). This dependence on molecular conformation is shown by the observation that recombinant Dsg1 and Dsg3, when expressed in baculovirus as secreted proteins, immunoadsorbs heterogeneous autoantibodies from PF and PV patients’ sera, and that this immunoadsorptive activity is lost upon denaturation by Ca2+ chelation, acid or alkaline treatment, or boiling. Furthermore, the importance of conformational epitopes was also demonstrated in the production of pathogenic Abs by mouse immunization (16, 17, 18). Therefore, a conventional approach using variously truncated Dsg molecules is inappropriate for definition of the conformational epitopes of Dsgs in pemphigus.
Dsg1 and Dsg3 have similar structures, but distinct epitopes. Recently, we have shown that Dsg1- and Dsg3-domain-swapped molecules are useful for characterization of the conformational epitopes of Dsg3 in PV (19). In this work, we extend the study, using 10 domain-swapped molecules and six point-mutated molecules to map conformational epitopes of Dsg1 and Dsg3. Competition ELISAs with these domain-swapped molecules reveal that dominant epitopes map to amino acid residues 26–87 of Dsg1 and 25–88 of Dsg3. Furthermore, within those regions we have identified important conformational epitopes at which amino acid substitutions alter the binding specificity of pemphigus autoantibodies. These findings are valuable for understanding the molecular mechanism of Dsg-mediated cell-cell adhesion, as well as for development of epitope-specific therapeutic strategies for pemphigus.
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Materials and Methods |
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TopAbstractIntroductionMaterials and MethodsResultsDiscussionReferences |
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Sera were obtained from 43 patients with PF and 40 patients with PV, whose diagnoses were confirmed by clinical, histologic, and immunopathologic findings. All PF sera were positive for anti-Dsg1 IgG and were negative for anti-Dsg3 IgG as determined by ELISA analysis using recombinant Dsg3 and Dsg1 (20, 21). Two PF (PF#73 and PF#2284) sera obtained by plasmapheresis were used for passive transfer study with neonatal mice. All PV sera were positive for anti-Dsg3 IgG autoantibodies and 14 of the PV samples were also positive for anti-Dsg1 IgG. In the PF samples, reactivity against Dsg1 was not reduced by immunoadsorption by Dsg3-His. Similarly, in the PV samples, reactivity against Dsg3 was not significantly altered by immunoadsorption by Dsg1-His.
Plasmid constructs
We previously constructed forms of recombinant Dsg1 and Dsg3
that are secreted upon expression in baculovirus (13, 14, 20, 22). These recombinant proteins contain the entire extracellular
domain of Dsg1 or Dsg3 fused with the constant region of human IgG1
and/or a His-tag. In this study, 10 domain-swapped molecules and six
Dsg3 point mutants were constructed (see Fig. 1
).
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) using pEVmod-PVIg (GenBank accession
number M76482) (13) and pKS-Dsg1 (GenBank accession number
X56654) as templates, respectively. For gross epitope mapping, four
domain-swapped constructs were produced that contained the constant
region of human IgG1 and a His-tag at the C terminus, as previously
described (19) (Fig. 1
A). To narrow the
pemphigus autoantibody epitopes, another six domain-swapped constructs
were produced, each containing an E-tag (Pharmacia Biotech, Uppsala,
Sweden) and a His-tag at their C termini (Fig. 1B). The PCR
products for the Dsg1 fragments comprising residues 1–87, 1–64 and
1–24, 89–496, and 63–496 and 26–496 were digested with
BglII/AatII, BglII/SpeI,
AatII/SalI, and SpeI/SalI,
respectively. The PCR products for Dsg3 fragments comprising residues
1–88, 1–63 and 1–26, 87–566, and 65–566 and 25–566 were digested
with BglII/AatII,
BglII/SpeI, AatII/XhoI, and
SpeI/XhoI, respectively. The resulting
products were ligated to BglII/XhoI-digested
vector pEVmod-His (20). These constructs were designated
Dsg11–87/Dsg387–566,
Dsg11–64/Dsg365–566,
Dsg11–24/Dsg325–566,
Dsg31–88/Dsg189–496,
Dsg31–63/Dsg163–496,
and
Dsg31–26/Dsg126–496.
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). In brief, the
megaprimer containing the mutation was generated by a first round of
PCR with a mutagenic primer (5'-GACTTGGTTGAATACTCACCAG-3')
and a plasmid template coding the extracellular domain of Dsg3
(pEVmod-Dsg3-His). This procedure eliminated a unique ScaI
restriction site (shown in boldface) in the ampr
gene (23). The megaprimer was then used to amplify
the entire plasmid with the same plasmid template in a second round of
PCR. After DpnI digestion, the PCR product was used for
transformation. All mutants were sequenced to verify the presence of
mutation and to ensure that no other mutations were introduced.
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The plasmids were cotransfected with BaculoGold baculovirus DNA
(BD PharMingen, San Diego, CA) into cultured insect Sf9 cells, and
recombinant viruses were collected from culture supernatant as
previously described (20, 22). High-Five cells cultured in
serum-free EX cell 405 medium (JRH Biosciences, Lenexa, KS) were
infected with high-titer virus stock and incubated for 3 days. The
culture supernatant contained 
5–10 µg/ml recombinant protein.
These proteins were purified on TALON affinity resin (Clontech, Palo
Alto, CA) according to the manufacturer’s recommendation.
Immunoblot analysis
The production of recombinant protein was confirmed by immunoblot analysis. Mouse anti-human Dsg3 mAb 5H10 (25) and anti-His-tag mAb (R&D Systems, Minneapolis, MN) were used as primary Abs, and a 1/1000 dilution of alkaline phosphatase-conjugated goat anti-mouse IgG Abs (Zymed Laboratories, San Francisco, CA) was used as the secondary Ab.
Competition ELISA analysis
Sera from pemphigus patients were preincubated at 4°C overnight either with the designated amount of purified recombinant protein in phosphate-buffered saline containing 1% BSA and 0.5 mM CaCl2 (PBS-Ca), or with culture supernatant containing recombinant protein. When culture supernatant was used, sera were diluted 200-fold. The sera were then subjected to ELISA against the entire extracellular domain of Dsg1 or Dsg3 (21). When necessary, sera were diluted to keep A450 below 1.2. Competition by immunoadsorption during preincubation was calculated using the formula: competition (%) = (1 - (A450exp - A450pos) / (A450neg - A450pos)) x 100. A450pos values for Dsg1 and Dsg3 are the measurements obtained for sera preincubated with recombinant Dsg1-His and recombinant Dsg3-His, respectively; A450neg is the measurement obtained for sera preincubated in PBS-Ca or in culture supernatant of uninfected High-Five cells; A450exp is the measurement obtained for sera preincubated with the recombinant protein of interest.
Passive transfer study with neonatal mice
To evaluate the pathogenic activity of PF sera that were
immunoadsorbed with domain-swapped molecules, we performed a passive
transfer study with neonatal mice, as previously described (13, 22). In brief, 5 ml of two PF sera (PF#73 and PF#2284) were
immunoadsorbed with either Dsg1-His, Dsg3-His,
Dsg11–161/Dsg3163–566, or
Dsg31–161/Dsg1164–496
purified on TALON affinity resin (Clontech) from 200 ml of culture
supernatant. IgG was prepared from the pass-through fraction by
precipitation with 40% ammonium sulfate, dialyzed against PBS, and
concentrated down to 600 µl with a microconcentrator, Centriprep
30 (Amicon, Beverly, MA). Then, 150 µl of IgG solution were injected
s.c. into neonatal ICR mice (12–24 h of age; body weight, 1.5–1.8 g).
The neonatal mice were examined and biopsied 18–24 h after the
injection to evaluate blister formation. At least three neonatal mice
were tested for each immunoadsorbed IgG fraction.
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Results |
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TopAbstractIntroductionMaterials and MethodsResultsDiscussionReferences |
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A series of Dsg1- and Dsg3-domain-swapped molecules and
point-mutated Dsg3 molecules were expressed in baculovirus as
secreted proteins (Figs. 1 and 2).
Dsg11–24/Dsg325–566,
Dsg11–64/Dsg365–566,
and
Dsg11–87/Dsg387–566 were
detected as doublets of 85 and 91 kDa;
Dsg31–26/Dsg126–496,
Dsg31–63/Dsg163–496, and
Dsg31–88/Dsg189–496 were
detected as doublets of 81 and 85 kDa; and Dsg3-M1-His to Dsg3-M6-His
were detected as doublets of 77 and 82 kDa. The lower band of each
doublet is most likely the result of proteolytic processing of
the prosequence present in the upper band, as previously described
(13, 14).
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). Competition increased
in a dose-dependent fashion, reaching a plateau at 2.5–10 µg/ml
competitor protein. Competition levels obtained using culture
supernatant containing recombinant proteins before purification were
nearly equal to or higher than the maximum competition level obtained
with purified proteins. Therefore, we used culture supernatant as the
source of competitor protein for subsequent competition ELISA.
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). Similarly, the reactivity of the PV sera against
Dsg3 was abolished by the extracellular domain of Dsg3, but was not
altered by that of Dsg1. These findings indicated that there was no
significant cross-reactivity between Dsg1 and Dsg3 in the pemphigus
patients’ sera tested in this study, and additionally showed that the
Dsg1- and Dsg3-domain-swapped molecules could be used for epitope
mapping. However, some original epitopes could be lost by making
swapping molecules due to the difference between Dsg1 and Dsg3
molecules, which is a limitation of our approach. We characterized epitopes recognized by anti-Dsg1 IgG in PF sera and by anti-Dsg3 IgG in PV sera. In addition, epitopes recognized by anti-Dsg1 IgG in PV sera were also examined, because mucocutaneous PV sera contain anti-Dsg1 IgG as well as anti-Dsg3 IgG.
Most conformational epitopes recognized by pemphigus Abs map to the N-terminal 161 amino acids of Dsg1 and Dsg3
Four domain-swapped molecules, Dsg11–401/Dsg3405–566, Dsg11–161/Dsg3163–566, Dsg31–403/Dsg1404–496, and Dsg31–161/Dsg1164–496 were used for gross mapping of conformational epitopes on Dsg1 and Dsg3.
For epitope mapping of anti-Dsg1 IgG in PF sera, each PF serum
sample was preincubated with baculovirus culture supernatant containing
one of the four recombinant proteins described above, Dsg1-IgHis
(positive control), or no recombinant protein (negative control). The
depleted samples were then subjected to ELISA analysis against Dsg1-His
and the level of competition for each domain-swapped molecule was
calculated. The results for the 43 PF sera tested are shown in the same
order in each plot (Fig. 4). The
order is determined by the level of competition found for
Dsg11–161/Dsg3163–566.
Residues 1–401 of Dsg1
(Dsg11–401/Dsg3405–566)
yielded an average competition level of 98.2% (Fig. 4A),
whereas residues 404–496 of Dsg1
(Dsg31–403/Dsg1404–496)
showed an average level of only 5.8% (Fig. 4C), indicating
that the critical epitopes for PF sera are in residues 1–401 of Dsg1.
Residues 1–161 of Dsg1
(Dsg11–161/Dsg3163–566)
yielded an average competition level of 62.5%; this level exceeded
50% in 30 (69.8%) of the 43 samples (Fig. 4B). In
contrast, residues 164–496
(Dsg31–161/Dsg1164–496)
yielded an average competition level of 16.5%, and this level exceeded
50% in only two (4.7%) samples (Fig. 4D). This finding
indicates that most of the epitopes recognized by anti-Dsg1 IgG in
PF sera are present in residues 1–161 of Dsg1. PF sera that were not
significantly competed by residues 1–161
(Dsg11–161/Dsg3163–566)
tended to display significant competition by residues 164–496
(Dsg31–161/Dsg1164–496),
suggesting that the epitopes for these PF sera are present in residues
164–401 of Dsg1.
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). Residues 1–403 of Dsg3
(Dsg31–403/Dsg1404–496)
yielded an average competition level of 85.8% (Fig. 5A),
whereas residues 405–566 of Dsg3
(Dsg11–401/Dsg3405–566)
yielded an average level of only 12.7% (Fig. 5C). Residues
1–161 of Dsg3
(Dsg31–161/Dsg1164–496)
yielded an average competition level of 67.4%; this level
exceeded 50% in 31 (77.5%) of the 40 samples (Fig. 5B). In
contrast, residues 163–566
(Dsg11–161/Dsg3163–566)
gave an average competition level of 17.8%, and this level exceeded
50% only in four (10%) samples (Fig. 5D). PV sera that
displayed no significant competition by residues 1–161
(Dsg31–161/Dsg1164–496)
tended to show significant competition by residues 163–566
(Dsg11–161/Dsg3163–566).
These findings indicate that most of the epitopes of anti-Dsg3 IgG
in PV sera are present in residues 1–161 of Dsg3 and that some minor
epitopes are present in the middle region of Dsg3 (residues 163–403).
A comparison of mucosal dominant and mucocutaneous PV sera showed no
significant differences in Dsg3 epitope mapping (data not shown).
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When taken together, our results show that the epitopes on Dsg1 and Dsg3 have a very similar distribution. Although the localization of epitopes was slightly different for each patient, most of the epitopes of PF and PV sera were located in the N-terminal 161 residues of Dsg1 and Dsg3, and some minor epitopes were found in the middle regions of Dsg1 (residues 164–401) and Dsg3 (residues 163–403). There were no apparent epitopes in the C-terminal extracellular domains of Dsg1 (residues 404–496) and Dsg3 (residues 405–566).
The N-terminal 161 residues of Dsg1 contain critical pathogenic epitopes for blister formation in PF
To show the relevance of the above epitope mapping to the
pathogenesis of PF, we performed a passive transfer study with neonatal
mice using immunoadsorbed PF sera by domain-swapped molecules. PF#73
showed 100 and 74.8% competition by residues 1–401 of Dsg1
(Dsg11–401/Dsg3405–566)
and residues 1–161 of Dsg1
(Dsg11–161/Dsg3163–566),
respectively, but no significant competition by residues 164–496 of
Dsg1
(Dsg31–161/Dsg1164–496)
or residues 404–496 of Dsg1
(Dsg31–403/Dsg1404–496)
(Fig. 6A). PF#2284 showed
96.3, 43.5, 12.5, and 5.9% competition by residues 1–401, 1–161,
164–496, and 404–496, respectively (Fig. 6B). Therefore,
PF#73 contains the dominant epitopes on the N-terminal 161 residues of
Dsg1, while PF#2284 contains some epitopes on the N-terminal 161
residues, as well as minor epitopes on the middle residues
164–401.
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and 7). Mice injected with PF#73 adsorbed
with residues 1–161 of Dsg1 showed markedly diminished in vivo IgG
deposition on keratinocyte cell surfaces and no apparent blister
formation (data not shown). In contrast, mice injected with PF#73
adsorbed with residues 164–496 demonstrated strong in vivo IgG
deposition and extensive blister formation (data not shown). Mice
injected with PF#2284 adsorbed with residues 1–161 of Dsg1 did not
show apparent blisters, while mice injected with PF#2284 adsorbed with
residues 164–496 showed extensive blisters, although both mice showed
in vivo IgG deposition (Fig. 7). The finding for PF#2284 indicated that
the removal of Abs against the epitopes on residues 1–161 was
sufficient to eliminate the pathogenic activity of this serum.
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Dominant conformational epitopes map to amino acids 26–87 of Dsg1 and 25–88 of Dsg3
To further narrow down critical conformational epitopes on the N-terminal regions of Dsg1 and Dsg3, six additional domain-swapped molecules (Dsg11–24/Dsg325–566, Dsg11–64/Dsg365–566, Dsg11–87/Dsg387–566, Dsg31–26/Dsg126–496, Dsg31–63/Dsg163–496, and Dsg31–88/Dsg189–496) were used in competition ELISA. These studies were performed using the 26 PF sera samples and the 30 PV sera samples that showed >50% competition with the N-terminal 161 residues of Dsg1 and Dsg3, respectively. The competition levels in this set of experiments were calculated relative to the results for residues 1–161 of Dsg1 or Dsg3.
Residues 1–24 of Dsg1
(Dsg11–24/Dsg325–566)
displayed an average of only 14.9% competition (Fig. 8A), whereas residues 26–161
(Dsg31–26/Dsg126–496)
displayed an average of 55.1% competition. Of the 26 PF sera samples,
13 (50%) gave >50% competition with residues 26–161 (Fig. 8D), indicating that the most of the epitopes are present in
the region C-terminal to residue 26 of Dsg1. In contrast, residues
1–87 yielded an average competition level of 41%, and this level was
>50% for 10 (38.5%) of the 26 samples (Fig. 8C). Residues
89–161 gave an average of only 18.4% competition (Fig. 8F), indicating that most of the epitopes are N-terminal to
residue 87. Residues 1–64
(Dsg11–64/Dsg365–566) and
63–161
(Dsg31–63/Dsg163–496) of
Dsg1 displayed average competition levels of 38.5 and 39.3%,
respectively (Fig. 8, B and E). Results for
mucocutaneous PV sera were similar (data not shown). These findings
indicate that most of the epitopes recognized by anti-Dsg1 IgG in
PF and PV sera are in the Dsg1 region comprised of residues 26–87.
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A), whereas residues 25–161
yielded an average of 80.8% competition. Twenty-six (86.7%) of the 30
PV samples yielded >50% competition with residues 25–161 (Fig. 9D), indicating that most of the Dsg3 epitopes are
C-terminal to residue 25. In contrast, residues 1–88 had an average
competition level of 53.3%, with 18 (60%) of the samples yielding
>50% competition (Fig. 9C). Residues 87–161 gave an
average of only 14.2% competition (Fig. 9F), indicating
that most of the epitopes are N-terminal to residue 88. Residues 1–63
(Dsg31–63/Dsg163–496) and
65–161
(Dsg11–64/Dsg365–566)
yielded an average of 22.1 and 38.2% competition, respectively (Fig. 9, B and E). These findings indicate that most of
the epitopes recognized by anti-Dsg3 IgG in PV sera are within
residues 25–88 of Dsg3.
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Comparison of the Dsg1 and Dsg3 amino acid sequences reveals that
the N-terminal EC1 or EC2 domains are more conserved than the
C-terminal EC3 or EC4 domains (2). The regions shown above
to contain the dominant conformational epitopes of Dsg1 and Dsg3 are in
the N-terminal EC1 domains. Residues 26–87 of Dsg1 include several
amino acids that are not conserved in Dsg3. Those nonconserved residues
are likely to define the specific epitopes of Dsg1 recognized by
anti-Dsg1 pemphigus autoantibodies. Six nonconserved Dsg3 clusters
were chosen, and site-directed mutagenesis was used to replace the
residues in these clusters with Dsg1-specific residues (Fig. 1C and Table II).
The six point-mutated Dsg3 proteins (Dsg3-M1 through -M6) were used as
competitors in ELISA with 26 PF sera, and competition levels were
measured against the entire extracellular domain of Dsg1 (Fig. 10). Interestingly, Dsg3-M1, which
contains His25, Cys28, and Ala29 of
Dsg1, gave an average of 19.7% competition, with >50% competition in
three (11.5%) of the 26 samples and >30% competition in seven (27%)
of the 26 samples. In contrast, no significant competition was observed
for the five other point-mutated Dsg3 proteins, although Dsg3-M2
yielded a slightly higher average competition level (8.8%) than the
remaining M3-M6 proteins (averages of 3–4.1%). This competition by
Dsg3-M1 was abolished by acid-treatment (0.1 M citrate, pH 3.0) (data
not shown), indicating that the Dsg1 epitope defined by Dsg3-M1 is
conformation-dependent (15). Similar studies with 12 PV
sera samples containing anti-Dsg1 IgG gave similar results; Dsg3-M1
protein exhibited a significantly higher competition level than did
other point-mutated Dsg3 molecules (data not shown). Taken together,
these findings demonstrate that one of the Dsg1-specific epitopes is
composed of residues His25, Cys28, and
Ala29.
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Discussion |
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TopAbstractIntroductionMaterials and MethodsResultsDiscussionReferences |
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We first performed gross mapping of the epitopes of Dsg1 and Dsg3,
using four domain-swapped molecules, which divide the entire
extracellular domain of Dsg1 and Dsg3 into three parts (Fig. 1A). In both PF and PV patients, most epitopes were mapped
to the respective N-terminal 161 residues of Dsg1 and Dsg3 (Figs. 4 and 5). These N-terminal 161 residues contained critical epitopes
recognized by pathogenic IgG Abs because the immunoadsorption of two PF
sera with residues 1–161 of Dsg1 removed their activity to induce
blisters in neonatal mice (Figs. 6 and 7). We then used another six
domain-swapped molecules to narrow down the dominant epitopes within
this region (Figs. 8 and 9). Although there was no single major epitope
on Dsg1 and Dsg3, dominant epitopes were mapped to residues 26–87 of
Dsg1 and 25–88 of Dsg3, both of which are in the N-terminal EC1
domain. Furthermore, within these residues, we found that one of the
epitopes of Dsg1 was defined by His25, Cys28,
and Ala29, using point-mutated Dsg3 molecules containing
Dsg1-specific residues (Fig. 10).
Although the three-dimensional molecular structures and precise functional domain maps of Dsg1 and Dsg3 remain to be elucidated, nuclear magnetic resonance spectroscopy and radiographic characterization have revealed the three-dimensional molecular structure of the N-terminal domains of classic cadherins (26, 27, 28, 29). It is generally agreed that the N-terminal domains (EC1 and EC2) of classic cadherin molecules have two dimer interfaces. One of these interfaces is formed between molecules in a parallel or lateral pair to form a lateral "strand dimer" believed to serve as a functional unit. The other interface is formed between molecules in an antiparallel pair and it is postulated that this interface corresponds to the adhesive interface between cadherins emanating from opposing cells. In addition to this structural evidence, biological evidence supports lateral dimerization or clustering as an essential step in mediating cell-cell adhesion by classic cadherins (30, 31, 32). It is postulated that each individual strand dimer interacts with an opposing strand dimer on another cell through the adhesive interfaces. According to the predicted crystallographic structure (27), side chains directly involved in adhesive interfaces come from residues 35, 37, 39, 44, 45, 53, 54, 55, 56, 79, 81, 83, 84, and 86. If we superimpose our mapping results of Dsg1 and Dsg3 on the predicted three-dimensional structure of classic cadherins, residues 26–87 of Dsg1 and 25–88 of Dsg3 correspond to the region forming the adhesive interfaces. Therefore, these findings suggest that the pathogenic autoantibodies in PF and PV may be dominantly raised against the adhesive interfaces of Dsg1 and Dsg3.
In contrast, Dsg epitopes recognized by some PF and PV autoantibodies
did not map to the N-terminal regions, but rather to the middle regions
of the molecules (Figs. 4 and 5). These sera showed no significant
competition with Dsg11–161 or Dsg31–161, but
did show competition with Dsg1164–496 or
Dsg3163–566. No significant clinical differences were
noted between patients with autoantibodies against the N-terminal
domains vs those with autoantibodies against the middle regions (data
not shown). Although these latter cases constitute a minor portion of
the total, the existence of such cases suggests that the pathogenic IgG
autoantibodies do not necessarily recognize the N-terminal region of
Dsg1 or Dsg3, and that autoantibodies against the middle portion of the
molecule may also be able to block the adhesive function of Dsg1 or
Dsg3 and induce the loss of keratinocyte adhesion.
It is intriguing that pemphigus autoantibodies are raised against the N-terminal rather than the C-terminal region of Dsg molecules. When the extracellular domains of Dsg1 and Dsg3 are compared, the homology is greater in the N-terminal regions than in the C-terminal regions. The identities between Dsg1 and Dsg3 are 73% in EC1, 65% in EC2, 57% in EC3, and 28% in EC4, with no significant homology for the EC5 domain (2). Therefore, specific recognition of Dsg1 or Dsg3 as "non-self" by the immune system would seem most likely to occur through Abs against the C-terminal regions, which contain more isotype-specific residues. However, pemphigus autoantibodies are not raised against the C-terminal domains. This finding may reflect some aspect of the pathophysiological mechanism that triggers the autoimmune reaction against Dsgs.
Our study is the first comprehensive conformational epitope mapping analysis of Dsg1 and Dsg3 in PV and PF. These findings provide new knowledge useful for elucidating the molecular mechanism of adhesion by Dsg1 and Dsg3, as well as the pathophysiological mechanism of blister formation in pemphigus. In addition, our finding provides a basis to develop epitope-specific therapeutic strategies for pemphigus.
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Acknowledgments |
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Footnotes |
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2 Address correspondence and reprint requests to Dr. Masayuki Amagai, Department of Dermatology, Keio University School of Medicine, 35 Shinanomachi, Shinjuku-ku, Tokyo 160-8582, Japan. E-mail address: amagai{at}sc.itc.keio.ac.jp
3 Abbreviations used in this paper: Dsg, desmoglein; PF, pemphigus foliaceus; PV, pemphigus vulgaris.
Received for publication November 27, 2000. Accepted for publication August 31, 2001.
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References |
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TopAbstractIntroductionMaterials and MethodsResultsDiscussionReferences |
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S. Thoma-Uszynski, W. Uter, S. Schwietzke, G. Schuler, L. Borradori, and M. Hertl Autoreactive T and B Cells from Bullous Pemphigoid (BP) Patients Recognize Epitopes Clustered in Distinct Regions of BP180 and BP230 J. Immunol., February 1, 2006; 176(3): 2015 - 2023. [Abstract] [Full Text] [PDF]
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C. M. Veldman, K. L. Gebhard, W. Uter, R. Wassmuth, J. Grotzinger, E. Schultz, and M. Hertl T Cell Recognition of Desmoglein 3 Peptides in Patients with Pemphigus Vulgaris and Healthy Individuals J. Immunol., March 15, 2004; 172(6): 3883 - 3892. [Abstract] [Full Text] [PDF]
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S. Ortiz-Urda, A. Elbe-Burger, J. Smolle, Y. Marquart, Y. Chudnovsky, T. W. Ridky, P. Bernstein, K. Wolff, and K. Rappersberger The Plant Lectin Wheat Germ Agglutinin Inhibits the Binding of Pemphigus Foliaceus Autoantibodies to Desmoglein 1 in a Majority of Patients and Prevents Pathomechanisms of Pemphigus Foliaceus In Vitro and In Vivo J. Immunol., December 1, 2003; 171(11): 6244 - 6250. [Abstract] [Full Text] [PDF]
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 N. Li, V. Aoki, G. Hans-Filho, E. A. Rivitti, and L. A. Diaz The Role of Intramolecular Epitope Spreading in the Pathogenesis of Endemic Pemphigus Foliaceus (Fogo Selvagem) J. Exp. Med., June 2, 2003; 197(11): 1501 - 1510. [Abstract] [Full Text] [PDF]
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K. Tsunoda, T. Ota, M. Aoki, T. Yamada, T. Nagai, T. Nakagawa, S. Koyasu, T. Nishikawa, and M. Amagai Induction of Pemphigus Phenotype by a Mouse Monoclonal Antibody Against the Amino-Terminal Adhesive Interface of Desmoglein 3 J. Immunol., February 15, 2003; 170(4): 2170 - 2178. [Abstract] [Full Text] [PDF]
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