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At least 19 recordsLinked to original sources
PubMed1990

Calgranulin expression and association with the keratinocyte cytoskeleton.

The molecules calgranulin A and B are two intracellular calcium-binding proteins which are expressed by the lesional keratinocytes of inflammatory dermatoses. We have investigated the induction of the calgranulin proteins in an in vitro system and characterized the epidermal form of calgranulin. Using calgranulin-specific monoclonal antibodies, we have shown that these proteins are expressed within the epidermis of skin explants after 12-24 h culture in vitro. The induction of calgranulin-specific staining on culture was prevented, however, by the inclusion of cycloheximide in the culture medium, in sufficient quantities to prevent de novo protein synthesis. Indirect immunofluorescence staining was used to analyse the subcellular localization of the calgranulin proteins. The specific staining pattern with antibodies which recognize the individual calgranulin proteins was retained in detergent insoluble cytoskeletal preparations of epidermis. In Western blotting experiments epidermal calgranulins could be solubilized only by using a urea-based protein extraction buffer. After sodium dodecyl sulphate (SDS) polyacrylamide gel electrophoresis of the epidermal extracts a single antigen, with a molecular weight of 13.0 kD was detected with the calgranulin-specific antibody MAC 387. The expression of calgranulins, similar to other members of the same protein family, may regulate cytoskeletal changes in skin disease.

Blotting, Western↗
PubMed1996

Rabbit polymorphonuclear neutrophils form 35S-labeled S-sulfo-calgranulin C when incubated with inorganic [35S]sulfate.

Rabbit peritoneal polymorphonuclear neutrophils reduced inorganic [35S]sulfate to [35S]sulfite in vitro, concomitant with incorporation of 35S into a 10.68-kDa cytosolic protein as a S-[35S]sulfo-derivative. Amino-terminal sequencing of the purified protein identified calgranulin C, a member of the S100 protein family. cDNA clones of calgranulins B and C were isolated using oligonucleotide primers based on the established amino acid sequences of other mammalian calgranulins. The complete amino acid sequence of rabbit calgranulin C was deduced from the nucleotide sequence of the corresponding cDNA. It comprises 91 amino acid residues, has a calculated molecular mass of 10.52 kDa, has 74% identity with porcine calgranulin C, and shows high homology with other S100 calcium-binding proteins. Rabbit calgranulin C has a single cysteine residue at position 30, which we believe to be modified to S-[35S]sulfo-cysteine as a consequence of sulfate reduction by neutrophils. The formation of S-[35S]sulfo-calgranulin C appears to be a reaction specific to neutrophils. The specific radioactivity of calgranulin C from the neutrophil culture medium was 50-fold greater than that of the calgranulin C within the cells, suggesting that S-sulfation of calgranulin C might be associated with its secretion.

Amino Acid Sequence↗
PubMed1994

Primary structure and binding properties of calgranulin C, a novel S100-like calcium-binding protein from pig granulocytes.

In this paper we report the biochemical characterization of calgranulin C, a new member of the S100 protein family. The protein is highly abundant in the cytosol of pig granulocytes, with relatively small amounts in lymphocytes. A simple protocol for the rapid purification of calgranulin C is described. The purified protein migrates as a single entity on SDS-polyacrylamide gel electrophoresis while it has two isoforms focusing at pH 5.8 and 5.5. Gel filtration and cross-linking experiments indicate that calgranulin C is capable of dimerization. The complete amino acid sequence was determined by Edman degradation of peptides generated by trypsin and V8 protease digestion. Calgranulin C consists of 91 residues and has a calculated molecular mass of 10,614 daltons. This value is virtually identical to that obtained by electrospray mass spectrometry. Sequence analysis predicts two EF-hand calcium-binding motifs, the first having an extended loop that is distinctive of the S100 protein family. The metal-binding properties were studied by means of a direct 45Ca(2+)-binding assay and by tyrosine fluorescence titration. Calgranulin C binds not only calcium but also zinc ions. A single high affinity Zn(2+)-binding site per monomer was evidenced by fluorimetric titration. Zinc binding to calgranulin C induces a remarkable increase in the protein affinity for calcium; in the absence of zinc, the protein binds 1 Ca2+/monomer with a binding constant of about 2 x 10(4) M-1, whereas the Zn(2+)-loaded form binds 2 Ca2+/monomer with Ka values of approximately 3 x 10(7) and 6 x 10(4) M-1. Circular dichroism analysis showed that the binding of calcium to calgranulin C induces a 15% decrease in the apparent alpha-helix content. This result and the calcium-dependent binding of the protein to a phenyl-Superose column strongly suggest that calgranulin C undergoes a gross conformational change upon calcium binding, thus supporting the idea that this protein may be involved in Ca(2+)-dependent signal transduction events.

Amino Acid Sequence↗
PubMed2006

Hexameric calgranulin C (S100A12) binds to the receptor for advanced glycated end products (RAGE) using symmetric hydrophobic target-binding patches.

Calgranulin C (S100A12) is a member of the S100 family of proteins that undergoes a conformational change upon calcium binding allowing them to interact with target molecules and initiate biological responses; one such target is the receptor for advanced glycation products (RAGE). The RAGE-calgranulin C interaction mediates a pro-inflammatory response to cellular stress and can contribute to the pathogenesis of inflammatory lesions. The soluble extracellular part of RAGE (sRAGE) was shown to decrease the inflammation response possibly by scavenging RAGE-activating ligands. Here, by using high resolution NMR spectroscopy, we identified the sRAGE-calgranulin C interaction surface. Ca2+ binding creates two symmetric hydrophobic surfaces on Ca2+-calgranulin C that allow calgranulin C to bind to the C-type immunoglobulin domain of RAGE. Apo-calgranulin C also binds to sRAGE using a completely different surface and with substantially lower affinity, thus underscoring the role of Ca2+ binding to S100 proteins as a molecular switch. By using native gel electrophoresis, chromatography, and fluorescence spectroscopy, we established that sRAGE forms tetramers that bind to hexamers of Ca2+-calgranulin C. This arrangement creates a large platform for effectively transmitting RAGE-dependent signals from extracellular S100 proteins to the cytoplasmic signaling complexes.

Amino Acid Sequence↗
PubMed1989

Calgranulin expression in inflammatory dermatoses.

We have used monoclonal antibodies to study the expression of calgranulins by keratinocytes in inflammatory dermatoses. Calgranulins are intracellular calcium binding proteins which have inflammatory cytokine activity and are composed of at least two different chains, calgranulin A and B. Antibody CF 145 and CF 557 identify calgranulin A and B, respectively. MAC 387 recognizes a molecule probably containing both calgranulins. Keratinocytes in normal skin did not contain these molecules. The keratinocytes in 52 cases of different inflammatory dermatoses showed expression of both calgranulin chains in lesional but not in non-lesional skin. Keratinocytes in inflammatory dermatoses therefore express an intracellular calcium binding protein which has cytokine activity.

Antibodies, Monoclonal↗
PubMed1998

Evidence that calgranulin is produced by kidney cells and is an inhibitor of calcium oxalate crystallization.

Urine produced by normal human kidneys is almost always supersaturated with respect to calcium oxalate (CaOx), the most common constituent of human kidney stones. Crystallization, with risk of renal damage and kidney stones, appears to be affected by molecules in urine that retard nucleation, growth, aggregation, and renal cell adherence of CaOx. The repertoire of such molecules is incompletely known. We have purified a 28-kDa protein from urine using salt precipitation, preparative isoelectric focusing, and sizing chromatography. Amino acid composition and NH2-terminal amino sequence analysis showed complete homology to calgranulin. Calgranulin was found to be a potent inhibitor of CaOx crystal growth (44% of control) and aggregation (50% of control) in the nanomolar range. Calgranulin cDNA was cloned from a human kidney expression library. Western analysis of human and rat kidney homogenates and mRNA temporal expression from two independent renal epithelial cell lines showed that calgranulin is produced in the kidney. Given its urinary abundance and potency, calgranulin may contribute importantly to the normal urinary inhibition of crystal growth and aggregation and therefore to the renal defense against clinical stone disease.

Animals↗
PubMed1992

Subunit structure of calgranulins A and B obtained from sputum, plasma, granulocytes and cultured epithelial cells.

The calcium-binding proteins calgranulins A and B co-purified with an elastase-specific inhibitor after the affinity and cation-exchange chromatography of the perchloric acid-soluble fraction of pooled sputum collected from patients with chronic obstructive pulmonary disease (Sallenave, J.-M. and Ryle, A.P. (1991) Biol. Chem. Hoppe-Seyler 372, 13-21). The calgranulins were separated from the inhibitor by reverse-phase FPLC. Protein blot analysis of the calgranulin fraction in the absence of reducing agent revealed a band of 25 kDa corresponding to the disulphide-bonded heterodimerization of the two monomer components. Similar results were obtained from the immunoprecipitation and protein blot analysis of plasma, granulocytes and cultured epithelial cells. This implies that the calgranulins exist in the heterodimeric form in secretions in vivo. Their association with pancreatic elastase during the affinity chromatography stage of purification implicates them in the tissue destruction elicited by the inflammatory response in chronic obstructive pulmonary diseases.

Calcium↗
PubMed2005

A strategy for high-resolution protein identification in surface-enhanced laser desorption/ionization mass spectrometry: calgranulin A and chaperonin 10 as protein markers for endometrial carcinoma.

Surface-enhanced laser desorption/ionization-mass spectrometry (SELDI-MS) has conventionally been practiced on linear time of flight (TOF) which has low mass accuracy and resolution. Here we demonstrate in an examination of both malignant and nonmalignant endometrial tissue homogenates that high mass accuracy and resolution in the MS stage are crucial. Using a commercially available quadrupole/TOF (QqTOF), we were able to resolve two potential cancer markers, subsequently identified off-line as chaperonin 10 and calgranulin A, that differ by 8 Da in mass. Two off-line protein identification protocols were developed: the first was based on size-exclusion chromatography (SEC), sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE), protein extraction, trypsin digestion, and matrix-assisted laser desorption/ionization-tandem MS (MALDI-MS/MS); the second on SEC and shotgun nano-liquid chromatography (nanoLC)-MS/MS. Analyses on a cohort of 44 endometrial homogenates showed 22 out of 23 nonmalignant samples had nondetectable to very low abundance of chaperonin 10 and calgranulin A; 17 of the 21 malignant samples had detectable to abundant levels of both proteins. Immunohistochemical staining of a tissue microarray of 32 samples showed that approximately half of malignant endometrial tissues exhibited positive staining for calgranulin A in the malignant epithelium, while 9 out of 10 benign tissues exhibited negative epithelial staining. In addition, macrophages/granulocytes in malignant as well as nonmalignant tissues showed positive staining. No immunostaining occurred in stroma or myometrium. Calgranulin A, in combination with chaperonin 10 and other proteins, may eventually constitute a panel of markers to permit diagnosis and screening of endometrial cancer.

Biomarkers, Tumor↗
PubMed2005

Transcript and proteome analysis reveals reduced expression of calgranulins in head and neck squamous cell carcinoma.

The calcium-binding proteins of the S100 and the annexin protein families have been implicated in a variety of important physiological functions including membrane remodeling, calcium-related intracellular signaling, cytoskeleton dynamics, tissue homeostasis, and formation of the cornified envelope in differentiating keratinocytes. Deregulated expression of members of these families has been reported in different types of neoplasia and other diseases, but the results were not consistent. Here we have applied a combination of cDNA microarrays, quantitative reverse transcriptase-PCR (qRT-PCR) and surface enhanced laser desorption ionisation-time of flight mass spectrometry (SELDI-TOF MS) to study differential expression of these genes in head and neck squamous cell carcinoma (HNSCC). The calgranulins A and B and annexins 1 and 2 were found to be down-regulated in HNSCC, compared with normal mucosa, at both the mRNA and protein level. Upon validation of the differential gene expression by tissue microarray immunohistochemistry, we detected novel expression patterns of calgranulins A and B both in normal mucosa as well as in HNSCC. In contrast to squamous cancer of skin and other cancers in which the calgranulins were found to be up-regulated, most HNSCC showed reduced and widely deranged staining patterns including heterogeneous nuclear, cytoplasmic and membranous staining, and even enhanced staining in the tumor stroma. These observations suggest that the normal function of the calgranulins A and B in mucosa might be different from that in skin.

Calgranulin A↗
PubMed1999

Calgranulin C has filariacidal and filariastatic activity.

The calgranulins are a family of calcium- and zinc-binding proteins produced by neutrophils, monocytes, and other cells. Calgranulins are released during inflammatory responses and have antimicrobial activity. Recently, one of the calgranulins, human calgranulin C (CaGC), has been implicated as an important component of the host responses that limit the parasite burden during filarial nematode infections. The goal of this work was to test the hypothesis that human CaGC has biologic activity against filarial parasites. Brugia malayi microfilariae and adults were exposed in vitro to 0.75 to 100 nM recombinant human CaGC. Recombinant CaGC affected adult and larval parasites in a dose-dependent fashion. Microfilariae were more sensitive to the action of CaGC than were adult parasites. At high levels, CaGC was both macrofilariacidal and microfilariacidal. At lower levels, the percentage of parasites killed was dependent on the level of CaGC in the culture system. The larvae not killed had limited motility. The filariastatic effect of low-level CaGC was reversed when the CaGC was removed from the culture system. Immunohistochemical analysis demonstrated that human CaGC accumulated in the cells of the hypodermis-lateral chord of adult and larval parasites. The antifilarial activity of CaGC was not due to the sequestration of zinc. Thus, the cellular and molecular mechanisms that result in the production and release of CaGC in humans may play a key role in the regulation of filarial parasite numbers.

Animals↗
PubMed1996

Complex assembly of calgranulins A and B, two S100-like calcium-binding proteins from pig granulocytes.

Calgranulin A (CAGA) and calgranulin B (CAGB) are two S100-like calcium-binding proteins that in human, bovine and mouse granulocytes are associated into a heterocomplex. We have previously identified in pig granulocytes the porcine homologue of CAGA and a novel S100-like protein which was named calgranulin C (CAGC). As pig CAGA is not associated with CAGC, we herein investigate its possible association with other proteins. CAGA was purified from pig granulocytes by gel filtration followed by Mono Q chromatography. The purified fractions were analysed by SDS-polyacrylamide gel electrophoresis, isoelectric focusing, mass spectrometry, chemical cross-linking and hydrophobic interaction chromatography. The CAGA-associated protein was further characterized by amino acid sequencing. Two CAGA-containing fractions were isolated. One of them was identified as a CAGA homodimer. The other fraction consists of a heterocomplex containing CAGA and a pI 7.0 calcium-binding protein; this protein has a molecular mass of 15,877.9 +/- 3.8 Da (mean +/- SD) whereas it migrates on 10 and 16% polyacrylamide gels as a 24- and 20-kDa protein, respectively. The pI 7.0 protein was identified by internal amino acid sequencing as the porcine homologue of CAGB. The stoichiometry of the heterocomplex was estimated to be 1:1. Both the CAGA homodimer and CAGA/CAGB were found to be non-covalently associated. Unlike the homodimer, CAGA/CAGB was bound to a Phenyl Superose column in a calcium-dependent manner. Our results suggest that pig granulocytes contain, in addition to CAGC, a CAGA homodimer and a CAGA/CAGB heterodimer. It is proposed that CAGB/CAGB and the CAGA homodimer may play different roles in vivo.

Amino Acid Sequence↗
PubMed1991

Morphological evidence for calcium-dependent association of calgranulin with the epidermal cytoskeleton in inflammatory dermatoses.

The association of calgranulins, intracellular calcium-binding proteins, with the keratinocyte cytoskeleton has been studied. These molecules are expressed in various inflammatory dermatoses and in organ-culture explants. Triton X-100 extraction in the presence of calcium or EDTA suggested that calgranulins are detergent insoluble in the presence of calcium. The molecules were localized in a plaque-like structure at the cell periphery in lesional skin and in organ-culture explants. Following induction of calgranulins in vitro there was a redistribution of the intermediate filament cytoskeleton into a perinuclear halo, although desmosomes remained intact. These various features suggest that these members of the S-100 protein family have a role in cytoskeletal changes seen in various skin diseases.

Blotting, Western↗
PubMed1990

Multimarker immunohistochemical staining of calgranulins, chloroacetate esterase, and S100 for simultaneous demonstration of inflammatory cells on paraffin sections.

Mac387 monoclonal antibody (MAb) recognizes two calcium binding, myeloid-associated proteins, now termed calgranulins, expressed at high levels by neutrophils and monocytes. Calgranulins are related to migration inhibitory factor (MIF) and are lost in a few days from monocytes differentiated in vitro. This marker is therefore potentially useful to analyze macrophage heterogeneity and turnover in tissue sections. In this study, we developed an immunohistochemical multimarker technique, including calgranulin demonstration, suitable for analyzing different inflammatory cells on paraffin-embedded material. The technique was carried out in subsequent steps demonstrating (a) naphthol AS-D chloroacetate esterase (CAE); (b) S100 immunoreactivity using a rabbit antibody in peroxidase-antiperoxidase (PAP) staining; and (c) Mac387 immunoreactivity using the alkaline phosphatase-anti-alkaline phosphatase (APAAP) technique. CAE staining was introduced in this method to distinguish Mac387+/CAE- macrophages from Mac387+/CAE+ neutrophils, and Mac387-/CAE+ mast cells. S100 protein is strongly expressed within lymphoid tissues by dendritic accessory cells and was then applied to distinguish these cells from S100-macrophages. We have also verified the possibility of reducing the staining time for this time-consuming procedure by use of microwave irradiation. The technique was applied to a representative variety of normal and pathological samples to assess its usefulness for study of cell heterogeneity. Our results showed the multimarker technique to be highly informative in the study of inflammatory lesions (e.g., rheumatoid arthritis, sarcoid and cat-scratch granulomas, dermathopathic lymphadenopathy), and is of wide potential value as an aid to histopathological diagnosis of several diseases.

Antibodies, Monoclonal↗
PubMed2003

Calgranulins in cystic fluid and serum from patients with ovarian carcinomas.

Ovarian cancer remains still associated with poor prognosis because it is diagnosed predominantly at advanced stages. Ovarian-specific tumor markers do not yet exist for early detection of the disease. At the search of diagnostic markers for ovarian cancer, proteomic-based approaches have focused on novel investigations of neoplastic processes in tumor patients. Cystic fluids of malignant and benign ovarian tumors and serum from the corresponding patients were collected and processed for two-dimensional gel electrophoresis. Proteins were visualized on the gels by silver staining. At the low molecular mass level between 10 and 20 kDa, selected protein spots were additionally processed for nanospray mass spectrometry and partial amino acid sequencing. For protein identification, the sequencing results were compared with computer information from a protein data bank. Protein patterns from cystic fluids of ovarian carcinomas differed significantly from those of benign cysts and revealed additional polypeptides at low molecular mass level between 10 and 20 kDa. Protein patterns from serum of patients with malignant ovarian tumors also contained additional polypeptides between 10 and 20 kDa that were not detected in serum from patients with benign cysts. The additional proteins in serum were present in similar electrophoretic positions compared with those found in the cystic fluid of the corresponding ovarian carcinomas. Protein spots in the range of 10-20 kDa were selected for partial amino acid sequencing. Two protein spots were identified as calgranulin A and three spots as calgranulin B. Either both proteins or only calgranulin A or B were present in cystic fluid from ovarian carcinomas and serum of the corresponding patients. These two proteins were absent or not detectable in fluid from benign ovarian cysts and in serum from those patients. Our investigations concerning protein patterns in cystic fluid of malignant and benign ovarian tumors provide new information about alterations in protein synthesis linked to neoplastic events of the ovary. With the proteomic strategy, new tumor markers are characterized and may serve for diagnostic purposes of patients with ovarian cancer.

Adult↗
PubMed2005

Psoriasin (S100A7) and calgranulin-B (S100A9) induction is dependent on reactive oxygen species and is downregulated by Bcl-2 and antioxidants.

S-100 proteins are calcium-binding proteins with important growth regulatory functions. Of these proteins, psoriasin and calgranulin-B have been shown to be highly upregulated in ductal carcinoma in situ (DCIS) of the breast and in psoriasis. The purpose of this study was to further elucidate the functional relevance of the overexpression of these two S-100 proteins in psoriasis and DCIS. We report the induction of both proteins by reactive oxygen species, phorbol ester TPA, and the induction of psoriasin in response to the PI3K inhibitor wortmannin. We also demonstrate that Bcl-2 overexpression represses the induction of psoriasin and calgranulin-B under these different conditions. The same effect was obtained with the antioxidant NAC, which indicates that the suppression of psoriasin and calgranulin-B induction is mediated by the antioxidant function of Bcl-2. Furthermore, we demonstrate that overexpression of a dominant negative IKKbeta also inhibits the induction of psoriasin suggesting that the NFkappaB pathway is involved in the induction of this protein. Also, we found NFkappaB responsive DNA elements in the upstream promoter region of psoriasin. MCF10A cells with a stable retroviral overexpression of psoriasin were significantly more resistant to H2O2-induced cell death than control cells further supporting the hypothesis that these S-100 proteins may play a role in oxidative stress response.

Acetylcysteine↗
PubMed1997

Cloning and sequence analysis of human and bovine corneal antigen (CO-Ag) cDNA: identification of host-parasite protein calgranulin C.

PURPOSE: The primary structure of a cornea-associated antigen (CO-Ag) has been identified and has been implicated in the pathogenesis of Mooren's ulcer. The study designs were to isolate full-length clones encoding CO-Ag from a bovine and a human corneal cDNA library so that complete sequence analyses might further define the possible role of this protein in Mooren's ulcer. METHODS: DNA fragments of bovine and human CO-Ag were generated using unique oligonucleotide primers and reverse transcription polymerase chain reaction. These fragments were used as probes to obtain cDNA clones from a bovine and a human corneal cDNA libraries. The clones with the longest cDNA inserts were selected for sequence analyses. Human cDNA fragment was digested with Stu I and Hind III and cloned into a expression vector, pPROEXHT, at the same restriction enzyme sites. The plasmid was transformed into E. coli cells. Correct cloning and the full-length sequence of human CO-Ag were determined by sequencing the insert cDNA. RESULTS: The bovine cDNA insert sequence was 273 nucleotides in length for the entire mRNA coding region, 212 nucleotides in the 5' untranslated region, 83 nucleotides in the 3' untranslated region and a poly(A) tail. The DNA base sequence of this clone also contained a standard initiation codon, termination codon, and the polyadenylation signal. This cDNA predicts a protein which contains 91 amino acids with a molecular weight of 10,584 daltons. Plasmid expression vector, pPROEXHT-CO-Ag, was constructed that direct the synthesis of human CO-Ag in E. coli as fusion protein. Human CO-Ag fusion protein was purified to 90% pure with a yield of 17.2 mg per liter of the bacterial cell lysate. The nucleotide sequence of the CO-Ag cDNA insert was completely identical to human neutrophil calgranulin C. The deduced amino acid sequence was completely identical to a Ca(2+)-binding protein isolated on the surface of filarial nematodes. CONCLUSIONS: The isolation and analysis of cDNA clones containing the complete coding sequence of bovine and human CO-Ag proteins is reported. The proteins identified by deduced amino acid sequences demonstrate 100% sequence homology with human and bovine calgranulin C. Immune recognition of calgranulin C to a filarial nematode may lead to a hyperactive autoimmune response to CO-Ag in the cornea leading to a Mooren's ulcer.

Amino Acid Sequence↗
PubMed1995

[Expression of calgranulin A and B in middle ear cholesteatoma].

Cholesteatoma epithelium is characterised by a keratinocyte dysregulation with a hyperproliferative growth and altered differentiation. Keratinocytes with a reduced turnover time show an increase of calcium binding proteins like calgranulin A and B. These proteins are highly linked with the modulation of cell growth and differentiation. The expression of calgranulin A and B was studied immunohistochemically using the monoclonal antibody F12 on cryosections of cholesteatoma biopsies. Normal skin served as control. The staining in normal skin was confined to the highly proliferative activated follicular keratinocytes, whereas most cholesteatomas showed a staining of all cell layers of the epithelium. Our findings show that the keratinocyte dysregulation of the cholesteatoma epithelium is reflected by variations of the expression of calcium binding proteins.

Biopsy↗
PubMed1992

Differential expression of calgranulin A and B in various epithelial cell lines and reconstructed epidermis.

The monoclonal antibody F12, raised against epidermal cells from a psoriatic lesion, decorated antigens highly expressed in psoriatic epidermis and in cultured normal human keratinocytes. In normal human skin, F12 reacted only with follicular keratinocytes. Characterization of the immunoprecipitated antigens by two-dimensional gel electrophoresis revealed their identity with calgranulin A and B. A semiquantitative study with various established epithelial cell lines demonstrated that the expression of calgranulin A and B in hyperproliferative keratinocytes correlates with their potential to undergo terminal differentiation. In epidermis reconstructed in vitro, the antigen expression was stimulated by retinoids and suppressed under vitamin A starvation.

Antibodies, Monoclonal↗