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PubMed1982

Aminopeptidase A is angiotensinase A. II. Biochemical studies on aminopeptidase A and M in rat kidney homogenate.

Biochemical fluorometric methods were used to investigate aminopeptidase A (APA; E.C.3.4.11.7) in the rat kidney homogenate and glomeruli and to compare it with aminopeptidase M (APM; E.C.3.4.11.2). It is shown that APA is a calcium-ion-dependent enzyme, while APM is not. To clarify the functional importance of APA and APM in the kidney, their activities were measured under the influence of angiotensins. Fluorimetric measurements in renal homogenate (with 2-naphthylamide derivatives as substrates), which represents mixed-enzyme tissue preparations containing a variety of peptidases besides APA and APM, showed a Km of 0.13 mM for APA and competitive inhibition of ANG II (K1 = 0.015 mM), and a Km of 0.24 for APM and competitive inhibition by ANG III (K1 = 0.003 mM). The remaining two angiotensins showed non-competitive inhibition of APA (ANG I, III) and APM (ANG I, II) in this preparation. For comparison purposes, fluorometric measurements were performed in microdissected glomeruli which contain only APA. A Km of 0.23 mM for the APA and a competitive inhibition of APA by ANG I and II were determined. Thus it was possible to show biochemically that APA is equivalent to angiotensinase A and that both APA and APM participate in angiotensin degradation in the kidney. APA initiating the breakdown of ANG I and II, and APM possibly continuing it in sequential fashion.

Aminopeptidases↗

PubMed2006

Localization of angiotensin II, the AT1 receptor, angiotensin-converting enzyme, aminopeptidase A, adipocyte-derived leucine aminopeptidase, and vascular endothelial growth factor in the human ovary throughout the menstrual cycle.

OBJECTIVE: To assess the expression and cellular distribution of angiotensin II (Ang II), angiotensin type 1 receptor (AT1R), angiotensin-converting enzyme (ACE), aminopeptidase A (APA), adipocyte-derived leucine aminopeptidase (A-LAP), and vascular endothelial growth factor (VEGF) in human ovarian tissue during the menstrual cycle. DESIGN: Ovarian tissues (n = 52) and corpora lutea (n = 34) were obtained from patients undergoing hysterectomy/oophorectomy, and tissue sections were immunostained for each antigen. SETTING: University hospital. PATIENT(S): Patients undergoing hysterectomy or oophorectomy for benign conditions. INTERVENTION(S): Immunostaining of tissue sections using antibodies to each antigen. MAIN OUTCOME MEASURE(S): Microscopic evaluation to assess the presence, distribution, and cellular localization. RESULT(S): The luteal tissue is the major site of Ang II, ACE, AT1R, and VEGF, with highest staining intensity found during the midluteal phase and at pregnancy. The AT1R was found in theca cells. The APA was strongly immunolocalized in pericytes. Immunolocalization of AT1R was almost similar to that of VEGF including oocytes in the primordial and intermediate follicles. CONCLUSION(S): The expression and distinct pattern of the cellular localization of Ang II and its related proteins in human ovarian tissue during folliculogenesis and in the luteal tissue suggest their roles in the growth and differentiation of theca, granulose, and luteal cells.

Aminopeptidases↗

PubMed1994

Differential inhibition of aminopeptidase A and aminopeptidase N by new beta-amino thiols.

Aminopeptidase A (APA) is a highly selective peptidase, which cleaves the N-terminal Glu or Asp residues of biologically active peptides, and has therefore been proposed to be involved in angiotensin II and CCK8 metabolism. Highly potent and selective APA inhibitors are consequently required to study the physiological regulation of these two peptides. Using, as a model, Glu-thiol (4-amino-5-mercaptopentanoic acid), which was the first efficient APA inhibitor described but is however equipotent on APA (0.14 microM) and aminopeptidase N (APN) (0.12 microM), several beta-amino thiol inhibitors have been synthesized. In these molecules, the length of the side chain was varied and the carboxylate group of Glu-thiol was replaced by other negatively charged groups, such as phosphonate, sulfonate, hydroxamate, and thiol. The inhibitory potency of one of these compounds, 22h (S)-3-amino-4-mercaptobutanesulfonate, was found to be nearly 100-fold better for APA than for APN, with an affinity (0.29 microM) almost equivalent to that of Glu-thiol. Hence, this compound is the first selective APA inhibitor reported, and as such, it should be an interesting probe to explore the physiological involvement of APA in the metabolism of neuropeptides like angiotensin II and CCK8.

Aminopeptidases↗

PubMed1994

Rat kidney glutamyl aminopeptidase (aminopeptidase A): molecular identity and cellular localization.

Glutamyl aminopeptidase [aminopeptidase A (EAP), EC 3.4.11.7] is an ectoenzyme that selectively hydrolyzes acidic amino acid residues from the amino terminus of oligopeptides. EAP activity is highest within the kidney and small intestine. The murine pre-B cell BP-1/6C3 and the human kidney glycoprotein gp160 differentiation antigens have been reported to have biochemical properties indistinguishable from EAP. It is not known, however, if rat kidney EAP is a homologue of these antigens or molecularly distinct. Using the reverse transcription-polymerase chain reaction method with oligonucleotide primers based on the BP-1/6C3 nucleotide sequence, we isolated a 450-bp partial cDNA from rat kidney poly(A)+ RNA. The partial cDNA encoded a predicted protein that was 92% and 86% identical to the murine BP-1/6C3 and human gp160 antigens, respectively; the amino acid sequence within the zinc-binding domain was completely conserved. Purification of EAP from rat kidney and microsequence analysis of a tryptic digest peptide fragment (18-mer) indicated that the fragment was highly similar to a region within the BP-1/6C3 and gp160 proteins. Northern blot hybridization and immunoblot analyses were also consistent with labeling of products the same size as reported for the BP-1/6C3 and gp160 antigens. There was a good correlation between the cellular distribution of EAP mRNA and EAP immunoreactivity, with proximal tubules and glomerular mesangial cells having the highest densities. These results indicate that rat kidney EAP is a species homologue of the murine BP-1/6C3 and human gp160 antigens. Furthermore, on the basis of its cellular localization, rat kidney EAP is likely to be involved in degradation of oligopeptides within the glomerulus and the glomerular filtrate. Since cells that express EAP also express receptors for angiotensin II, an intrarenal vasoactive hormone that is a substrate for EAP, these results further suggest that EAP may play a role in modulating the activity of intrarenal angiotensin II.

Amino Acid Sequence↗

PubMed1996

Peptide hydrolysis in lens: role of leucine aminopeptidase, aminopeptidase III, prolyloligopeptidase and acylpeptidehydrolase.

The distribution of leucine aminopeptidase, aminopeptidase III, prolyloligopeptidase and acylpeptidehydrolase activities in different regions of a bovine lens was determined and correlated with the distribution of crystallin fragments (measured as < 18 kDa protein) and water-insoluble proteins in the same lens. A gradient of activity was observed for all the peptidases tested, with the highest specific activity present in the cortical fibers which decreased to one half or below in the inner cortical fibers and nucleus. An inverse correlation between peptidase activities and the amount of crystallin fragments was observed in different regions of the lens. However, a direct correlation between the water-insoluble protein content and the crystallin fragments was observed in all fibers of the same lens. The amount of crystallin fragments and the amount of water-insoluble proteins increased from 2.7% and 8% in the outer cortical fibers to 13% and 68% in the nucleus of the same lens. The water-insoluble fraction from both cortical and nuclear fibers however displayed 4-5 fold more crystallin fragments compared to that present in the water-soluble fraction of the same preparation. When the bovine lens cortical and nuclear extracts were tested for their ability to hydrolyze the peptide substrate, Ile-Ser-bradykinin, the cortical extract was found to be at least ten times superior to the nuclear extract. Prior inactivation of prolyloligopeptidase and other serine proteases by diisopropylfluorophosphate however diminished the ability of the cortical extract to hydrolyze peptide substrates. Bovine lens cortical extract was able to completely hydrolyze alpha-melanocyte stimulating hormone as well as N-Acetyl-Met-Asp-Arg-Val-Leu-Ser-Arg-Tyr showing the presence of active acylpeptidehydrolase facilitating the complete hydrolysis of N-terminally blocked peptides. The human lens extract was found to contain both diisopropylfluorophosphate sensitive and resistant enzymes capable of hydrolyzing peptide substrates.

Amino Acid Sequence↗

PubMedDate not supplied

Colpocytograms and maternal serum placental cystine aminopeptidase, tissue cystine aminopeptidase, alkaline phosphatase and heat stable alkaline phosphatase activity in monitoring the last four weeks before delivery in high-risk pregnancy.

On the basis of the results of serial enzyme and cytohormonal assays in the last lunar month of gestation in 232 pergnant patients with high-risk pregnancy, it has been shown that the "at term" and inflammatory smears, which persist for over five days before labor, and post-partum" smears, significantly correlate with abnormal (low or decreasing) results of serum placental cystine aminopeptidase activity and with the pathologic course of pregnancy and labor as well as with the poor neonates' condition. The average serum placental and tissue cystine aminopeptidase determinations were the lowest in women with "post-partum" smears or persisting "at term" smears. These activities reached their highest they temporarily decreased. The oxytocinase activity curves in women with cytolytic smears were similar to those in patients with the "before term" smear patterns, which persisted before delivery. The average oxytocinase activity in women with the inflammatory smears was at first the highest and later it decreased most rapidly of all the groups under consideration. The maternal serum alkaline phosphatase and its heat-stable fraction in pregnant patients with "post-partum" and persisting "at term" smears were at first the lowest and just before labor the highest of all the cytologic pregnancy patterns. Colpocytograms confirmed their high prognostic value when compared with the enzyme tests of placental function.

Alkaline Phosphatase↗

PubMed1997

Localization of alanyl aminopeptidase and leucyl aminopeptidase in cells of Pseudomonas aeruginosa by application of different methods for periplasm release.

Various methods for the isolation of periplasm were examined and compared with regard to the complete release of known periplasmic marker enzymes and the contamination of the periplasm by cytosol for Pseudomonas aeruginosa PAO1 as a significant Gram-negative test strain. The aim of the investigations was to clarify the exact localization of alanyl aminopeptidase (AAP) and leucyl aminopeptidase (LAP) of this microorganism and to evaluate these methods. The osmotic shock of NOSSAL and HEPPEL (1996) was the most effective method with the lowest contamination by the cytosolic marker enzyme malic enzyme, but some proteins, which are located near the inner side of the cytoplasmic membrane, can be released additionally into the periplasm. All other procedures like chloroform or polymyxin treatment, the magnesium chloride washing of intact bacteria and spheroblasting by lysozyme in the presence of EDTA or magnesium chloride resulted only in a partial, sometimes only very low release of periplasm. The periplasmic enzymes are bound either more by hydrophobic or more by ionic interactions to the cell envelope and show a different behaviour with the different releasing agents. These methods are useful for a further differentiation between really periplasmic protein, and those proteins, which were false positive found in periplasm as a result of the osmotic shock. Our results show that AAP from Pseudomonas aeruginosa is a periplasmic enzyme with hydrophobic interactions to the cytoplasmic membrane, corresponding to the early results of LAZDUNSKI and MURGIER for Escherichia coli (LAZDUNSKI et al. 1975a and b, MURGIER et al. 1977), and LAP is cytosolic, but located near the cytoplasmic membrane. The AAP is not a real amphipatic membrane protein, as could be demonstrated by phase separation experiments with Triton X-114.

Acid Phosphatase↗

PubMed1979

A new colorimetric method for the determination of serum enzyme, gamma-glutamyl transpeptidase, cystine aminopeptidase, and leucine aminopeptidase.

A new colorimetric method for the serum enzyme assay was developed, using the color reaction of a ferrous salt complex and a primary aromatic amine. For this method new substrates containing primary aromatic amines were synthesized. The aromatic amine liberated by the enzyme reaction was measured by its color reaction with pentacyanoammineferroate treated with hydrogen peroxide. The determination was made at a wavelength of around 700 nm, at which the assay is not affected by colored substances in serum. Therefore a blank assay was not necessary. This method was applied to the assay of serum gamma-glutamyl transpeptidase, cystine aminopeptidase, and leucine aminopeptidase. The results obtained were in good agreement with those of the p-nitroanilide method also used to assay each enzyme. This new method can be used on a Technicon autoanalyzer system.

Acyltransferases↗

PubMed1997

The main neutral aminopeptidase activity of human lymphoid tumour cell lines does not originate from the aminopeptidase N-(APN; CD13) gene.

Lymphocytes and related cell lines are predominantly CD13-negative, however, there are reports describing neutral aminopeptidase activity in or on these cells. The aim of this study was to answer the question, whether this activity originates from APN-gene expression. The total cellular activities (Ala-pNA hydrolysis) of lymphoid cell lines are up to 15 times higher than that of normal lymphocytes. Despite weak or lacking CD13 surface expression all lymphoid cell lines tested contain APNmRNA as quantified by competitive RT-PCR as well as low enzymatic activity in their particulate fractions. By isoelectric focusing two enzyme species with isoelectric points of 5.4 or between 3.5 to 4.8, respectively, were detected. To investigate whether these activities result from APN-gene we established transfectants lacking cellular APN expression of the CD13-positive histiocytic cell line U937 and the CD13-negative T-cell line H9. Studies on these transfectants proved (I) that the main neutral aminopeptidase activity expressed in lymphoid cells is definitively not related to APN and (II) that APN is also expressed in lymphoid cells, although on a low level only.

Aminopeptidases↗

PubMed1998

Inhibition of Streptomyces griseus aminopeptidase and effects of calcium ions on catalysis and binding--comparisons with the homologous enzyme Aeromonas proteolytica aminopeptidase.

Streptomyces griseus aminopeptidase is a zinc metalloenzyme containing 2 mol zinc/mol protein, similar to the homologous enzyme Aeromonas proteolytica aminopeptidase. In addition, a unique Ca2+-binding site has been identified in the Streptomyces enzyme, which is absent in the Aeromonas enzyme. Binding of Ca2+ enhances stability of the Streptomyces enzyme and modulates its activity and affinity towards substrates and inhibitors in a structure-dependent manner. Among the three hydrophobic 4-nitroanilides of alanine, valine and leucine, the latter displays the largest overall activation (increase in k(cat)/Km). Large enhancements in affinity (1/Ki) upon Ca2+ binding have been observed for inhibitors with flexible (leucine-like) residues at their N-termini and smaller enhancements for inhibitors with rigid (phenylalanine-like) residues.

Aeromonas↗

PubMed2003

Aminopeptidase C of Aspergillus niger is a novel phenylalanine aminopeptidase.

A novel enzyme with a specific phenylalanine aminopeptidase activity (ApsC) from Aspergillus niger (CBS 120.49) has been characterized. The derived amino acid sequence is not similar to any previously characterized aminopeptidase sequence but does share similarity with some mammalian acyl-peptide hydrolase sequences. ApsC was found to be most active towards phenylalanine beta-naphthylamide (F-beta NA) and phenylalanine para-nitroanilide (F-pNA), but it also displayed activity towards other amino acids with aromatic side chains coupled to beta NA; other amino acids with non-aromatic side chains coupled to either pNA or beta NA were not hydrolyzed or were poorly hydrolyzed. ApsC was not able to hydrolyze N-acetylalanine-pNA, a substrate for acyl-peptide hydrolases.

Amino Acid Sequence↗

PubMed2003

Shedding of the type II IL-1 decoy receptor requires a multifunctional aminopeptidase, aminopeptidase regulator of TNF receptor type 1 shedding.

Proteolytic cleavage of the extracellular domain of the type II IL-1 decoy receptor (IL-1RII) generates soluble IL-1-binding proteins that prevent excessive bioactivity by binding free IL-1. In this study we report that an aminopeptidase, aminopeptidase regulator of TNFR1 shedding (ARTS-1), is required for IL-1RII shedding. Coimmunoprecipitation experiments demonstrate an association between endogenous membrane-associated ARTS-1 and a 47-kDa IL-1RII, consistent with ectodomain cleavage of the membrane-bound receptor. A direct correlation exists between ARTS-1 protein expression and IL-1RII shedding, as cell lines overexpressing ARTS-1 have increased IL-1RII shedding and decreased membrane-associated IL-1RII. Basal IL-1RII shedding is absent from ARTS-1 knockout cell lines, demonstrating that ARTS-1 is required for constitutive IL-1RII shedding. Similarly, PMA-mediated IL-1RII shedding is almost entirely ARTS-1-dependent. ARTS-1 expression also enhances ionomycin-induced IL-1RII shedding. ARTS-1 did not alter levels of membrane-associated IL-1RI or IL-1R antagonist release from ARTS-1 cell lines, which suggests that the ability of ARTS-1 to promote shedding of IL-1R family members may be specific for IL-1RII. Further, increased IL-1RII shedding by ARTS-1-overexpressing cells attenuates the biological activity of IL-1beta. We conclude that the ability of ARTS-1 to enhance IL-1RII shedding represents a new mechanism by which IL-1-induced cellular events can be modulated. As ARTS-1 also promotes the shedding of the structurally unrelated 55-kDa, type I TNF receptor and the IL-6R, we propose that ARTS-1 may play an important role in regulating innate immune and inflammatory responses by increasing cytokine receptor shedding.

Aminopeptidases↗

PubMed1990

[Urinary excretion of glycine.prolile dipeptidile aminopeptidase, N-acetyl-beta-D-glucosaminidase, alanine aminopeptidase and low molecular protein in patients with renal cell carcinoma].

Urinary excretion of glycine.prolile dipeptidile aminopeptidase (GP-DAP), N-acetyl-beta-D-glucosaminidase (NAG), alanine aminopeptidase (AAP) and beta 2-microglobulin (beta 2-M), alpha 1-microglobulin (alpha 1-M) was studied preoperatively in 32 patients with renal cell carcinoma. The excretion indices of GP-DAP, AAP and NAG were significantly higher than those in the healthy control group. The excretion of these enzymes obviously reflected the degree of the tumor progression. However, positive rates were not remarkable (37% for GP-DAP, 37% for AAP and 28% for NAG). The excretion of beta 2-M and alpha 1-M was not increased in renal cell carcinoma patients.

Acetylglucosaminidase↗

PubMed1977

Thermophilic aminopeptidase. IV. Cooperative effects in ANS binding by the thermophilic aminopeptidase I from B. stearothermophilus.

Aminopeptidase I is a membrane-bound metalloenzyme isolated from B. stearothermophilus which is thermostable and requires Co2+ for activity. The Co, Zn, and metal-free enzyme were titrated with ANS, and cooperative binding was noted with the active Co enzyme but not with the Zn (5% active) or apo (inactive) enzymes. There are a number of sites for ANS on each of the three enzyme forms and the agreement between the association constants of the Zn enzyme (identical and independent sites) and the non-cooperative sites of the Co enzyme suggest that these sites are intrinsically similar. However, binding to the first of these sites in the Co enzyme triggers a cooperative binding of a second molecule of ANS, and this cooperative binding is related to a concomitant decrease in enzymatic activity. The correspondence can be shown by comparison of the inhibition constant for the hydrolysis of Gly-Leu-Tyr (Ki-1=13,300 cm3/mmol) and the association constant for the cooperating site (12,500 cm3/mmol). The significance of these observations is discussed in terms of the nature of the binding sites and the possible consequences of the interactions on the regulation of aminopeptidase I activity.

Aminopeptidases↗

PubMed2006

Crystal structure of aminopeptidase N (proteobacteria alanyl aminopeptidase) from Escherichia coli and conformational change of methionine 260 involved in substrate recognition.

Aminopeptidase N from Escherichia coli is a broad specificity zinc exopeptidase belonging to aminopeptidase clan MA, family M1. The structures of the ligand-free form and the enzyme-bestatin complex were determined at 1.5- and 1.6-A resolution, respectively. The enzyme is composed of four domains: an N-terminal beta-domain (Met(1)-Asp(193)), a catalytic domain (Phe(194)-Gly(444)), a middle beta-domain (Thr(445)-Trp(546)), and a C-terminal alpha-domain (Ser(547)-Ala(870)). The structure of the catalytic domain exhibits similarity to thermolysin, and a metal-binding motif (HEXXHX(18)E) is found in the domain. The zinc ion is coordinated by His(297), His(301), Glu(320), and a water molecule. The groove on the catalytic domain that contains the active site is covered by the C-terminal alpha-domain, and a large cavity is formed inside the protein. However, there exists a small hole at the center of the C-terminal alpha-domain. The N terminus of bestatin is recognized by Glu(121) and Glu(264), which are located in the N-terminal and catalytic domains, respectively. Glu(298) and Tyr(381), located near the zinc ion, are considered to be involved in peptide cleavage. A difference revealed between the ligand-free form and the enzyme-bestatin complex indicated that Met(260) functions as a cushion to accept substrates with different N-terminal residue sizes, resulting in the broad substrate specificity of this enzyme.

Amino Acid Sequence↗

PubMedDate not supplied

Increased expression of interleukin-8 and aminopeptidase N by cell-cell contact: interleukin-8 is resistant to degradation by aminopeptidase N/CD13.

In rheumatic joints, high concentrations of interleukin-8 (IL-8) have been measured in synovial fluid and in pannus tissue. In both locations aminopeptidase N (APN)/CD13, an exopeptidase with reported activity towards IL-8 is also present. The surprising stability of IL-8 in the presence of an alleged IL-8-degrading peptidase prompted us to undertake the present study. Cocultivation of fibroblast-like synoviocytes (SFC) with T cells or with T lymphocytic cell membranes, or of T cells with SFC cell membranes, all resulted in increased IL-8 mRNA expression and IL-8 secretion into the medium, and an increase of APN expression on lymphocytes. IL-8 degradation was monitored by Western blots and HPLC. IL-8(72), as a partially processed form, was used throughout this study since it is abundant in tissues and has increased biological activity in comparison to IL-8(77). Thus its degradation/inactivation is considered of high biological significance. Whereas trypsin as a positive control rapidly degraded IL-8, we did not see any IL-8 degradation, either by a variety of soluble APNs, by leucine aminopeptidase or by APN expressed on the surface of SFC, or on ECV304 cells transfected with an APN expression vector. The much more sensitive HPLC technique resulted in negative results as well.

CD13 Antigens↗

PubMed1997

A dominant negative mutation in Saccharomyces cerevisiae methionine aminopeptidase-1 affects catalysis and interferes with the function of methionine aminopeptidase-2.

Methionine aminopeptidase (MetAP) enzymes require the metal ion cobalt, but little is known about the role of cobalt in the structural stability or catalysis of these enzymes. In Escherichia coli MetAP, for which a crystal structure is available, the five amino acid residues liganding the two cobalt ions are Asp97, Asp108, His171, Glu204, and Glu235. These five amino acids are conserved in all MetAPs sequenced to date. The C-terminal domain of the yeast Saccharomyces cerevisiae MetAP1 is 41% identical to E. coli MetAP and contains these cobalt coordinating residues. Using site-directed mutagenesis on the gene coding for yeast MetAP1, we replaced Asp219 (corresponding to Asp97 in E. coli MetAP) with Asn. The yeast D219N mutant enzyme has 10(3)-fold lower catalytic activity and a different substrate specificity when compared to wild-type yeast MetAP1. These results indicate that the side-chain of Asp219 is important for catalysis. Expression of D219N-MetAP1 in yeast causes a slow-growth phenotype and interferes with wild-type MetAP1 in a dominant manner. Expression of D219N-MetAP1 also affects the function of S. cerevisiae MetAP2.

Aminopeptidases↗

PubMed1998

Regulation of the expression of aminopeptidase A, aminopeptidase N/CD13 and dipeptidylpeptidase IV/CD26 in renal carcinoma cells and renal tubular epithelial cells by cytokines and cAMP-increasing mediators.

Aminopeptidase (AP) A is a transmembrane type II molecule widely distributed in mammalian tissues. Since APA expression may be absent in renal cell carcinoma (RCC), it is possible that there is an altered regulation or other defect of APA upon malignant transformation of proximal tubular cells. However, investigations into the regulation of APA on tumour cells are rare. We report, for the first time, that both transforming growth factor-beta 1 (TGF-beta1) and tumour necrosis factor-alpha (TNF-alpha) down-regulate APA mRNA as well as protein expression in renal tubular epithelial cells and RCC cells in culture. In addition to this, both cytokines decrease dipeptidylpeptidase (DP) IV/CD26 mRNA, but not APN/CD13 mRNA expression. Otherwise, IL-4 and IL-13 increase CD13 as well as CD26 expression, but do not alter APA expression. Interferon-alpha (IFN-alpha), IFN-beta and IFN-gamma increase mRNA expression of all the three membrane ectopeptidases, whereas IL-1, IL-6, IL-7, IL-12 and granulocyte-macrophage colony-stimulating factor (GM-CSF) have been found to be without any significant effect. Treatment of cultured cells with cAMP-increasing agents, such as 8-bromo-cAMP or A23187, results in an increase in APA and DPIV/CD26, but no change in APN/CD13 mRNA expression or even a decrease in it. Furthermore, AP inhibitors can influence APA mRNA expression, since bestatin causes an increase in APA expression in a time- and dose-dependent manner, whereas bestatin does not change CD13 or CD26 expression. No difference could be found with respect to the modulation by different mediators between RCC cells and renal epithelial cells, though permanent tumour cell lines such as Caki-1 and Caki-2 may have lost some of the normally expressed peptidases.

Adjuvants, Immunologic↗