(Journal of Leukocyte Biology. 2001;70:59-64.)
© 2001
by Society for Leukocyte Biology
Dimeric S100A8 in human neutrophils is diminished after phagocytosis
Rakesh K. Kumar*,
Zheng Yang*,
Susan Bilson*,
Soula Thliveris*,
Bridget E. Cooke
and
Carolyn L. Geczy*
* School of Pathology, University of New South Wales, Sydney, Australia; and
Department of Anatomical Pathology, Prince of Wales Hospital, Randwick, Australia
Correspondence: R. K. Kumar, School of Pathology, University of New South Wales, Sydney, Australia 2052. E-mail:
R.Kumar{at}unsw.edu.au
 |
ABSTRACT
|
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S100A8 is a major cytoplasmic protein of neutrophils and
monocytes/macrophages and has been associated with myeloid cell
differentiation and activation. Little is known about its functions or
mechanisms of release from neutrophils. We have developed a monoclonal
antibody to murine S100A8, which cross-reacts with human S100A8. This
antibody, which recognizes the homodimeric form of the protein, detects
its expression specifically in human neutrophils and is reactive in
formalin-fixed, paraffin-embedded tissues. Using this antibody as well
as a commercially available antibody to human S100A8, we show that
phagocytic activation of neutrophils, in vivo in acute
appendicitis and in vitro following phagocytosis of
opsonized zymosan, is characterized by loss of cytoplasmic
immunoreactivity for S100A8. In vitro, phagocytosis is
associated with rapid diminution of immunostaining without loss of
viability. Loss of immunoreactivity for S100A8 may serve as a marker of
localized neutrophil activation in tissues.
Key Words: acute inflammation neutrophil activation immuno-histochemistry S100 proteins
 |
INTRODUCTION
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The S100 proteins designated S100A8 and S100A9 have been detected
in the cytoplasm of neutrophils, monocytes, and tissue macrophages at
sites of inflammation. These proteins are believed to be present as
noncovalent heterodimers, which constitute approximately 40% of the
cytosolic protein of neutrophils [1
]. Intracellular
functions are still incompletely understood [2
] but
include a role in regulation of neutrophil activation involving
Ca2+-dependent signaling [3
] and involvement
in transporting unsaturated fatty acids [4
].
Extracellular S100A9 has anti-microbial activity, possibly by virtue of
its ability to chelate zinc [5
]. A9 may also modulate
the affinity of integrins expressed on neutrophils [6
],
and A8 inhibits this activity [6
]. S100A9 inhibits the
oxidative burst of bacillus Calmette-Guerin (BCG)-activated macrophages
and suppresses inflammatory pain [7
, 8
].
High levels of extracellular A8/A9 complex are suggested markers of
disease activity in inflammatory disorders such as arthritis and
ulcerative colitis [9
, 10
]. Whether the
complex is released by dying cells [11
] or its presence
is a result of active secretion remains unclear. The proteins lack
signal sequences associated with classical secretory pathways, although
a tubulin-dependent mechanism of secretion by monocytes is suggested
[12
]. There is no information available about mechanisms
of secretion of A8 and/or A9 by neutrophils.
Our laboratory has a long-standing interest in a murine S100 protein,
originally designated CP-10 [13
], the nearest human
counterpart to which is S100A8 [14
]. Unlike human
S100A8, from which it exhibits substantial sequence divergence, CP-10
is a potent chemoattractant for phagocytic cells [15
].
However, like the human protein, it is expressed in high amounts by
neutrophils and by activated macrophages [16
,
17
] so that it has come to be known as murine S100A8
(mA8) [18
]. Previously, we demonstrated that in murine
experimental-acute alveolitis induced by bleomycin, large quantities of
this protein are released into the extracellular fluid in a
biologically active, monomeric form, apparently by recruited
neutrophils [19
]. In the present study, we have used
antibodies to human and murine S100A8 to examine the expression of the
A8 protein by human neutrophils, in vivo and in
vitro. We show for the first time that homodimeric S100A8 is
present in the cytoplasm of human neutrophils and that following
phagocytosis, neutrophils exhibit rapid loss of cytoplasmic
immunoreactivity for homodimeric S100A8, which may serve as a marker of
localized neutrophil activation in tissues.
 |
MATERIALS AND METHODS
|
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Preparation of a rat monoclonal antibody (mAb) to mA8
Sprague-Dawley rats, aged 34 weeks (Animal Resources Centre,
Perth, Western Australia), were immunized on days 0, 9, and 14 with
710 µg bacterial fusion protein of mA8 with glutathione
S-transferase (GST) bound to glutathione-agarose
beads. Popliteal lymph-node cells from immunized animals were
harvested, mixed with myeloma cells (P3-X63-Ag8.653) at a ratio of
2.5:1 [20
], and fused in 50% polyethylene glycol (Merck
4000, Merck, Rahway, NJ). Cells were resuspended in a mixture
of RPMI 1640 medium, 20% fetal calf serum, 40% rat
thymocyte-conditioned medium, and 1%
hypoxanthine-aminopterin-thymidine, then dispensed into 96-well plates,
and pre-seeded with macrophage feeder cells. Hybridoma supernatants
were screened 1221 days post-fusion with an indirect enzyme
immunoassay using plates coated with 500 ng/well of CP-10/GST fusion
protein or GST alone. Of the 131 hybridomas tested, 13 positive clones
were detected, which were unreactive to GST, and of these, five were
re-cloned twice after selecting for immunoglobulin G (IgG)-positive
clones. The mAb designated CP10.1 was selected for further use, based
on its high immunoreactivity with native and recombinant mA8 as well as
with relevant target cells. Because the hybridoma could not be grown as
an ascites in mice or rats, cells were maintained in appropriately
supplemented HY medium (Sigma Chemical Co., St. Louis, MO).
Immunoblotting
Recombinant S100A8, S100A9, or S100A12 (2 µg) purified from C4
reverse-phase HPLC [21
] was lyophilized, resuspended in
50 mM Tris-HCl, pH 7.5, and oxidized in 2 mM copper sulfate at room
temperature for 30 min. The formation of homo- or heterodimers was
confirmed by polyacrylamide gel electrophoresis (PAGE) and silver
staining. Samples were mixed with an equal volume of 2x loading
buffer, heated at 100°C for 3 min, and analyzed by 10% tricine
sodium dodecyl sulfate (SDS)-PAGE [22
]. Gels run in
parallel were silver stained or transferred to polyvinylidene
difluoride membranes (Millipore, Bedford, MA). Antigenic reactivity of
the S100 protein monomers and dimers to the rat mAb CP10.1 or the 85-C2
mouse mAb (BMA Biomedicals AG, Augst, Switzerland) was detected using
horseradish peroxidase (HRP)-conjugated, goat anti-mouse or anti-rat
IgG (Bio-Rad, Hercules, CA), respectively, and visualized by
chemiluminescence [enhanced chemiluminescence (ECL) system, Amersham
Australia, Sydney, Australia].
Immunostaining
Immunostaining was performed using a capillary-action staining
system as described previously [19
]. Cells expressing
cytoplasmic immunoreactivity for S100 A8 were identified using CP10.1
or 85-C2. For sections of archival, formalin-fixed blocks of tissue
from tuberculous lymph nodes and acute appendicitis, antigen retrieval
was performed by boiling in 0.01 M citrate buffer, pH 6.0, for 10 min.
Sections were washed with phosphate-buffered saline (PBS) containing
0.1% Triton X-100 and blocked with 50% normal rabbit serum for 10 min
at 37°C. They were then incubated for 30 min at 37°C with an
appropriate concentration of the primary antibody. Sections were washed
four times with PBS-Triton after this and each subsequent incubation.
Bound antibody was detected by sequential, 30-min incubations with
biotinylated rabbit anti-rat or anti-mouse IgG (Dako, Sydney,
Australia), followed by a complex of streptavidin (Boehringer Mannheim,
Sydney, Australia) and biotinylated HRP in PBS-1% bovine serum albumin
(BSA). Diaminobenzidine was used as the substrate, and sections were
counterstained lightly with hematoxylin. For cytospin preparations, a
similar procedure was used, but antigen retrieval was not required, and
nuclei were counterstained with methyl green.
Enzyme immunoassay
Wells of a microtitre plate (Nunc, Roskilde, Denmark) were
coated with 500 ng recombinant human or murine S100A8 (prepared
according the protocols described in ref. [16
] and
comprising a mixture of monomeric and dimeric forms) in
carbonate-bicarbonate buffer, pH 9.6, for 2 h at 37°C, washed
four times with Tris-buffered saline (TBS; pH 7.4) containing 0.01%
Tween-20, blocked with TBS-Tween containing 0.1% ovalbumin for 60 min
at 37°C, and washed again. To compare the binding of CP10.1 with the
two forms of S100A8, serial dilutions of mAb supernatant were added to
the wells in triplicate and incubated overnight at 4°C. To assess
competitive inhibition, a 1:25 dilution of CP10.1 antibody was added to
each well of a plate coated with human S100A8 in the presence of
0.050.5 µg/ml recombinant murine or human S100A8. The wells were
then washed four times, and bound antibody was detected by incubation
for 60 min at room temperature with biotinylated rabbit, anti-rat IgG,
followed by additional washes and incubation with streptavidin-HRP
complex (Amersham Australia). Enzyme activity was revealed by
incubation with ABTS substrate (Kirkegaard & Perry,
Gaithersburg, MD), and the reaction product was read using a Titertek
Multiskan photometer with a 405 nm filter.
Stimulation of neutrophils in vitro
Freshly collected blood samples were layered onto Mono-Poly
Resolving medium (Ficoll-Hypaque, ICN Biomedicals, Aurora, OH),
according to the manufacturers instructions and centrifuged at 600
g for 1 h. Neutrophils removed from the interface were
washed twice and resuspended in RPMI 1640 at 5 x 106
cells/ml.
Neutrophils were exposed to N-formyl-Met-Leu-Phe (fMLP;
10-7 M; Sigma) or to opsonized zymosan for 15 min or
2 h. Opsonized zymosan was prepared according to the method of
Markert et al. [23
] and used at dilutions
ranging from 1:11:20. After incubation, aliquots of the neutrophil
suspension were removed for assessment of viability using trypan blue
exclusion and for preparation of cytospin slides. The latter were
air-dried, fixed in 2% paraformaldehyde for 30 min, rinsed in PBS for
at least 5 min, and stored at 4°C.
 |
RESULTS
|
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Specificity of CP10.1 antibody
Immunblotting demonstrated that mAb CP10.1 reacted with human
S100A8 but not with S100A9 or with S100A12 (Fig. 1
). Of interest was the observation that whereas the mAb 85-C2
detected monomeric and dimeric forms of S100A8, CP10.1 only reacted
with the homodimer.

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Figure 1. Immunoblotting of monomeric and dimeric forms of S100A8, S100A9, and
S100A12 using CP10.1 and 85-C2 mAbs reacted against monomeric S100A8
(A8m), homodimeric S100A8 (A8d), monomeric S100A9 (A9m), homodimeric
S100A9 (A9d), a 1:1 mixture of oxidized S100A8 and S100A9 (A8/9), or
S100A12 (A12). (A) 85-C2 reacts with monomeric and dimeric forms of
S100A8 but not with S100A9 or S100A12. (B) CP10.1 reacts only with
homodimeric S100A8 and exhibits no cross-reactivity with S100A9 or
S100A12. (C) The corresponding silver-stained gel shows the migration
patterns of the S100 proteins. Note that A8 + 9 contains
homodimeric A8 (20 kDa), A8/A9 heterodimeric complex (24 kDa), and
homodimeric A9 (28 kDa).
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CP10.1 reactivity with human S100A8 was confirmed by titration
and cross-absorption experiments. Using an enzyme immunoassay in which
human or murine S100A8 was immobilized onto a plastic surface,
comparable binding of CP10.1 to both proteins was demonstrated
(Fig. 2
). Furthermore, binding to human S100A8 was inhibited specifically
by increasing concentrations of human or murine S100A8 (with >90%
inhibition of binding of a 1:25 dilution by 100 ng/ml of either
protein).

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Figure 2. Binding serial dilutions of CP10.1 antibody to wells coated with 500 ng
recombinant human or murine S100A8 or to control wells. Values are
optical density at 405 nm (mean±SE of triplicate
samples).
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Cellular immunolabeling with CP10.1 antibody
The 85-C2 mAb to human S100A8 strongly labeled neutrophils and
macrophages in tissue sections of human lymph node (Fig. 3A
). In contrast, CP10.1 antibody generated against murine S100A8
appeared to label only neutrophils (Fig. 3B)
. This difference in
specificity was obvious, particularly when immunostaining sections of
granulomas in tuberculous lymph nodes in which modified macrophages,
including morphologically distinctive epithelioid and giant cells, were
labeled by 85-C2, whereas only neutrophils in the caseous necrotic
center were recognized by CP10.1 (Fig. 3C
and 3D)
.

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Figure 3. Immunolabeling leukocytes by antibodies to S100A8 in sections of human
lymph node involved by tuberculous lymphadenitis. (A) Using 85-C2
antibody, reactivity of intravascular neutrophils and tissue
macrophages in subcapsular tissue is apparent, whereas in B, only
neutrophils are labeled by CP10.1 antibody. (C) 85-C2 antibody labels
epitheloid cells in a tuberculous granuloma, as well as neutrophils in
the caseous necrotic center, and in D, only neutrophils exhibit
immunoreactivity with CP10.1 antibody.
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Immunostaining neutrophils in tissues by CP10.1 was blocked by excess
human or murine S100A8 (unpublished results). It is interesting that
immunostaining by 85-C2 was blocked by human but not by murine S100A8.
Immunolabeling neutrophils in acute appendicitis by CP10.1
Using a polyclonal antibody to S100A8, we showed that in an
experimental inflammatory lesion in mice, neutrophils were apparently
activated to release S100A8, with loss of immunoreactivity in tissue
sections [19
]. To investigate whether a similar process
occurred in human inflammatory lesions, sections of acute appendicitis
were immunostained for S100A8 using CP10.1 antibody. An obvious
gradation of intensity of immunostaining of neutrophils was observed
from the serosa to the lumen. Intense staining of cells was noted in
the serosa, where the neutrophils are recruited as part of an exudative
inflammatory response (Fig. 4A
). Staining intensity diminished through the muscularis and the
mucosa, which are sites of bacterial invasion in established
appendicitis (Fig. 4B and 4C)
. In the lumen, which contained large
numbers of neutrophils participating in the suppurative inflammatory
response, virtually none of the cells exhibited positive staining (Fig. 4D) . Identical results with respect to immunostaining of neutrophils
were obtained with the 85-C2 antibody (unpublished results).

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Figure 4. Immunolabeling neutrophils for S100A8 in various layers of the appendix
in acute appendicitis, using CP10.1 antibody. (A) Intense reactivity of
neutrophils in the serosa is obvious, whereas in B, the staining of
neutrophils in between the smooth-muscle fibersis less
marked. Neutrophils infiltrating the mucosal layer in C are still less
strongly reactive, and the cells in the (D) lumen exhibit no
immunostaining for S100A8.
|
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Immunolabeling neutrophils by CP10.1 after stimulation in
vitro
Next, we investigated whether the loss of immunoreactivity of
neutrophils for S100A8 at an inflammatory site in vivo could
be triggered by exposure to bacterial products or required activation
by phagocytosis. Following activation with fMLP, isolated neutrophils
remained strongly immunoreactive for S100A8 with CP10.1 and 85-C2 mAbs
and were indistinguishable from the unstimulated, control cells
(Fig. 5A
). In contrast, neutrophils that had phagocytozed opsonized
zymosan demonstrated markedly diminished immunoreactivity after 15 min
of incubation, with a proportion exhibiting no staining at all (Fig. 5B)
. This loss of immunostaining was observed using both mAbs. It is
important that cells that had reduced immunoreactivity exhibited no
evidence of selective loss of viability as estimated by trypan blue
exclusion (Table 1
). Indeed, the viability of all three preparations was virtually
identical after 15 min, by which time loss of immunoreactivity was
apparent already. After 2 h, only the cells exposed to fMLP showed
any noticeable decrease in viability relative to controls, yet these
cells were still strongly immunoreactive for S100A8.

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Figure 5. Isolated human neutrophils immunolabeled for S100A8 using CP10.1
antibody. (A) Neutrophils exposed to 10-7 M
fMLP remained strongly immunoreactive. (B) Many of the neutrophils that
had phagocytosed opsonized zymosan exhibited markedly diminished
reactivity (e.g., vertical arrow) with some cells completely failing to
stain for S100A8 (horizontal arrow).
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 |
DISCUSSION
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In this study, we show that homodimeric S100A8 is present in the
cytoplasm of human neutrophils. Activated neutrophils lose
immunoreactivity for S100A8, in vitro and in
vivo, and apparently, this is related to phagocytosis. In
vitro, loss of cytoplasmic immunostaining is not associated with
any reduction in viability.
Demonstration of changes in cytoplasmic immunoreactivity of neutrophils
was facilitated by a novel mAb, which we designated CP10.1, raised
against murine S100A8 and cross-reactive with human S100A8. This
exhibited specific staining of the protein in human neutrophils. In
earlier studies, there has been conflicting information about patterns
of immunostaining for S100A8 in different inflammatory lesions (e.g.,
refs. [24
, 25
]). However, most such
antibodies were poorly characterized in terms of epitopes recognized.
Variability in staining patterns may be a consequence of
cross-reactivity with other S100 proteins, which is likely in view of
their high degree of sequence homology, particularly in the
calcium-binding and N-terminal domains [26
]. At least
some mAbs to S100A8 cross-react with S100A9 [27
], and
others recognize the A8/A9 complex preferentially [28
].
Among antibodies specific for S100A8, different commercially available
antibodies apparently recognize different epitopes on S100A8, because
some permit demonstration of immunoreactivity in formalin-fixed,
paraffin-embedded tissue (with or without antigen retrieval), whereas
others do not.
However, differential staining of neutrophils and monocytes by an
antibody to S100A8 has not been shown previously. The CP10.1 antibody
specifically recognizes an epitope on homodimeric S100A8, which is
evidently present on human and murine S100A8, is distinct from the
epitopes recognized by other antibodies, and is expressed only by the
protein in neutrophils. Of particular value for immunocytochemistry is
the preservation of the neutrophil-specific epitope in
paraffin-embedded tissues. Thus, the antibody to murine S100A8 provides
a unique reagent with which to investigate the expression of this
protein by human neutrophils.
In acute appendicitis, the inflammatory response is triggered by
bacterial proliferation within the lumen, with subsequent spread of
organisms through the wall of the appendix leading to transmural
inflammation. Therefore, neutrophils in the lumen are virtually certain
to have encountered and phagocytosed bacteria, whereas those in the
serosal layers are less likely to have participated in a phagocytic
response. In this context, the differential intensity of staining for
S100A8 of neutrophils in the various layers of the appendicular wall
could be explained in terms of phagocytic activation following
interaction with the bacteria. Whether this represents extracellular
release of the protein or alteration of the intracellular protein
leading to loss of immunoreactivity is unclear. Release of neutrophil
S100A8 in response to bacterial infection has not been demonstrated in
human disease, although previously, we have shown high levels of S100A8
in murine abscess fluid [29
].
To ascertain whether the loss of immunoreactivity was more likely to
have been elicited by exposure to bacterial products or by the
phagocytic response, we examined neutrophils activated by the potent
bacterial chemoattractant fMLP, compared with cells that had
phagocytosed particles of opsonized zymosan. There was no alteration in
immunostaining following exposure to an optimal chemoattractant
concentration of fMLP, whereas reactivity was reduced rapidly and
strikingly after phagocytosis. This suggests that phagocytosis is an
important trigger for the diminution of cytoplasmic immunoreactivity
for S100A8, although it is unlikely to be the only one, because
previously, we have demonstrated loss of neutrophil immunoreactivity
for S100A8 in a model of alveolitis in which no particulate irritant
was present [19
]. The reduction in immunostaining was
not merely a consequence of leakage of the protein from dead or dying
cells, because there was no evidence of any selective decrease in
neutrophil viability after engulfment of particles. Thus, it is
possible that the loss of immunoreactivity might be a consequence of
release of S100A8 by active secretion. However, we were unable to
demonstrate convincingly increased levels of S100A8 in cellular
supernatants commensurate with the loss of immunoreactivity by
immunoblotting or enzyme immunoassay, although clearly, A8 and A9 were
present in the supernatants (unpublished results).
Earlier studies demonstrate Ca2+-dependent translocation of
the S100A8/A9 complex to the membrane of neutrophils activated with
fMLP or activated zymosan [3
, 30
], and
these proteins are postulated to regulate Ca2+-dependent
processes important in neutrophil migration, phagocytosis, and
activation. Guignard et al. [31
] show that
maximal A8/A9 translocation was provoked by zymosan, whereas that by
fMLP was relatively weak. The mechanism by which cytoplasmic
immunoreactivity for A8 is lost is unclear. One possibility is that it
might be related to alteration of protein conformation or redox state,
e.g., by hypochlorite generated by activated neutrophils, so that the
epitope recognized by the CP10.1 antibody on homodimeric S100A8 is no
longer available. However, immunostaining using the 85-C2 antibody was
diminished in parallel, in vitro and in vivo,
suggestive of extracellular release of the protein. In any case, loss
of immunoreactivity for S100A8 appears to be a marker of phagocytically
activated neutrophils.
If neutrophil S100A8 is released, it would be of interest to establish
whether this occurs as the free protein (monomeric or oligomeric) or in
association with S100A9. In parallel experiments using a polyclonal
antibody to human S100A9, we noted comparable loss of immunostaining
for A9 (unpublished results), consistent with release of the complex.
An important and as yet unresolved issue is the function of S100A8
following release. In the light of studies of anti-microbial activity
of the A8/A9 complex and of zinc sequestration by A9 in the complex
[5
], release in response to phagocytosis of bacteria
could be important in microbial defense. Of particular interest,
however, is that S100A8 can be oxidized rapidly by hypochlorite to
yield novel oxidation products ([32
] and unpublished
results), and an intriguing possibility is that it may minimize
nonspecific tissue damage by neutrophil-derived, reactive oxygen
species. Clearly, further investigation of these issues is needed.
 |
ACKNOWLEDGEMENTS
|
|---|
This work was supported by grants from the National Health and
Medical Research Council of Australia and by the Community Health and
Anti-Tuberculosis Association.
Received June 19, 2000;
revised February 21, 2001;
accepted February 22, 2001.
 |
REFERENCES
|
|---|
-
Hessian, P. A., Edgeworth, J., Hogg, N. (1993) MRP-8 and MRP-14, two abundant Ca2+-binding proteins of neutrophils and monocytes J. Leukoc. Biol. 53,197-204[Abstract]
-
Donato, R. (1999) Functional roles of S100 proteins, calcium-binding proteins of the EF-hand type Biochim. Biophys. Acta 1450,191-231[Medline]
-
Guignard, F., Mauel, J., Markert, M. (1995) Identification and characterization of a novel human neutrophil protein related to the S100 family Biochem. J. 309,395-401
-
Roulin, K., Hagens, G., Hotz, R., Saurat, J. H., Veerkamp, J. H., Siegenthaler, G. (1999) The fatty acid-binding heterocomplex FA-p34 formed by S100A8 and S100A9 is the major fatty acid carrier in neutrophils and translocates from the cytosol to the membrane upon stimulation Exp. Cell Res. 247,410-421[Medline]
-
Sohnle, P. G., Hunter, M. J., Hahn, B., Chazin, W. J. (2000) Zinc-reversible antimicrobial activity of recombinant calprotectin (migration inhibitory factor-related proteins 8 and 14) J. Infect. Dis. 182,1272-1275[Medline]
-
Newton, R. A., Hogg, N. (1998) The human S100 protein MRP-14 is a novel activator of the ß2 integrin Mac-1 on neutrophils J. Immunol. 160,1427-1435[Abstract/Free Full Text]
-
Aguiar-Passeti, T., Postol, E., Sorg, C., Mariano, M. (1997) Epithelioid cells from foreign-body granuloma selectively express the calcium-binding protein MRP-14, a novel down-regulatory molecule of macrophage activation J. Leukoc. Biol. 62,852-858[Abstract]
-
Giorgi, R., Pagano, R. L., Dias, M. A. A., Aguiar-Passeti, T., Sorg, C., Mariano, M. (1998) Antinociceptive effect of the calcium-binding protein MRP-14 and the role played by neutrophils on the control of inflammatory pain J. Leukoc. Biol. 64,214-220[Abstract]
-
Brun, J. G., Jonsson, R., Haga, H. J. (1994) Measurement of plasma calprotectin as an indicator of arthritis and disease activity in patients with inflammatory rheumatic diseases J. Rheumatol. 21,733-738[Medline]
-
Roseth, A. G., Aadland, E., Jahnsen, J., Raknerud, N. (1997) Assessment of disease activity in ulcerative colitis by faecal calprotectin, a novel granulocyte marker protein Digestion 58,176-180[Medline]
-
Lehrer, R. I. (1993) Holocrine secretion of calprotectin: a neutrophil-mediated defense against Candida albicans? J. Lab. Clin. Med. 121,193-194[Medline]
-
Rammes, A., Roth, J., Goebeler, M., Klempt, M., Hartmann, M., Sorg, C. (1997) Myeloid-related protein (MRP) 8 and MRP14, calcium-binding proteins of the S100 family, are secreted by activated monocytes via a novel, tubulin-dependent pathway J. Biol. Chem. 272,9496-9502[Abstract/Free Full Text]
-
Geczy, C. L. (1996) Regulation and proinflammatory properties of the chemotactic protein, CP-10 Biochim. Biophys. Acta 1313,246-252[Medline]
-
Lackmann, M., Cornish, C. J., Simpson, R. J., Moritz, R. L., Geczy, C. L. (1992) Purification and structural analysis of a murine chemotactic cytokine (CP-10) with sequence homology to S-100 proteins J. Biol. Chem. 267,7499-7504[Abstract/Free Full Text]
-
Lackmann, M., Rajasekariah, P., Iismaa, S. E., Jones, G., Cornish, C. J., Hu, S. P., Simpson, R. J., Moritz, R. L., Geczy, C. L. (1993) Identification of a chemotactic domain of the pro-inflammatory S100 protein CP-10 J. Immunol. 150,1-11[Abstract]
-
Iismaa, S. E., Hu, S. P., Kocher, M., Lackmann, M., Harrison, C. A., Thliveris, S., Geczy, C. L. (1994) Recombinant and cellular expression of the murine chemotactic protein, CP-10 DNA Cell Biol 13,183-192[Medline]
-
Hu, S. P., Harrison, C., Xu, K., Cornish, C. J., Geczy, C. L. (1996) Induction of the chemotactic S100 protein, CP-10, in monocyte/macrophages by lipopolysaccharide Blood 87,3919-3928[Abstract/Free Full Text]
-
Kerkhoff, C., Klempt, M., Sorg, C. (1998) Novel insights into structure and function of MRP8 (S100A8) and MRP14 (S100A9) Biochim. Biophys. Acta 1448,200-211[Medline]
-
Kumar, R. K., Harrison, C. A., Cornish, C. J., Kocher, M., Geczy, C. L. (1998) Immunodetection of the murine chemotactic protein CP-10 in bleomycin-induced pulmonary injury Pathology 30,51-56[Medline]
-
Kearney, J. F., Radbruch, A., Liesegang, B., Rajewsky, K. (1979) A new mouse myeloma cell line that has lost immunoglobulin expression but permits the construction of antibody-secreting hybrid cell lines J. Immunol. 123,1548-1550[Abstract/Free Full Text]
-
Raftery, M. J., Harrison, C. A., Alewood, P., Jones, A., Geczy, C. L. (1996) Isolation of the murine S100 protein MRP14 (14 kDa migration-inhibitory-factor-related protein) from activated spleen cells: characterization of post-translational modifications and zinc binding Biochem. J. 316,285-293
-
Schagger, H., von Jagow, G. (1987) Tricine-sodium dodecyl sulfate-polyacrylamide gel electrophoresis for the separation of proteins in the range from 1 to 100 kDa Anal. Biochem. 166,368-379[Medline]
-
Markert, M., Andrews, P. C., Babior, B. M. (1984) Measurement of O2-production by human neutrophils. The preparation and assay of NADPH oxidase-containing particles from human neutrophils Methods Enzymol. 105,358-365[Medline]
-
Zwadlo, G., Bruggen, J., Gerhards, G., Schlegel, R., Sorg, C. (1988) Two calcium-binding proteins associated with specific stages of myeloid cell differentiation are expressed by subsets of macrophages in inflammatory tissues Clin. Exp. Immunol. 72,510-515[Medline]
-
Brandtzaeg, P., Dale, I., Gabrielsen, T. O. (1992) The leucocyte protein L1 (calprotectin): usefulness as an immunohistochemical marker antigen and putative biological function Histopathology 21,191-196[Medline]
-
Kligman, D., Hilt, D. C. (1988) The S100 protein family Trends Biochem. Sci. 13,437-443[Medline]
-
Guignard, F., Mauel, J., Markert, M. (1996) The monoclonal antibody Mac 387 recognizes three S100 proteins in human neutrophils Immunol. Cell Biol. 74,105-107[Medline]
-
Hogg, N., Allen, C., Edgeworth, J. (1989) Monoclonal antibody 5.5 reacts with p8,14, a myeloid molecule associated with some vascular endothelium Eur. J. Immunol. 19,1053-1061[Medline]
-
Kocher, M., Kenny, P. A., Farram, E., Abdul Majid, K. B., Finlay-Jones, J. J., Geczy, C. L. (1996) Functional chemotactic factor CP-10 and MRP-14 are abundant in murine abscesses Infect. Immun. 64,1342-1350[Abstract]
-
Lemarchand, P., Vaglio, M., Mauel, J., Markert, M. (1992) Translocation of small cytosolic calcium-binding protein (MRP-8) to plasma membrane correlates with human neutrophil activation J. Biol. Chem. 267,19379-19382[Abstract/Free Full Text]
-
Guignard, F., Mauel, J., Markert, M. (1996) Phosphorylation of myeloid-related proteins MRP-14 and MRP-8 during human neutrophil activation Eur. J. Biochem. 241,265-271[Medline]
-
Harrison, C. A., Raftery, M. J., Walsh, J., Alewood, P., Iismaa, S. E., Thliveris, S., Geczy, C. L. (1999) Oxidation regulates the inflammatory properties of the murine S100 protein S100A8 J. Biol. Chem. 274,8561-8569[Abstract/Free Full Text]
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