scholarly journals Monoclonal antibodies that specifically recognize neoepitope sequences generated by ‘aggrecanase’ and matrix metalloproteinase cleavage of aggrecan: application to catabolism in situ and in vitro

1995 ◽  
Vol 305 (3) ◽  
pp. 799-804 ◽  
Author(s):  
C E Hughes ◽  
B Caterson ◽  
A J Fosang ◽  
P J Roughley ◽  
J S Mort

Monoclonal antibodies have been prepared that react specifically with the neoepitopes present on proteoglycan degradation products generated from the proteolytic cleavage of aggrecan in the interglobular domain. Antibody BC-3 recognizes the new N-terminus (ARGSV...) on aggrecan degradation products produced by the action of the as yet uncharacterized proteolytic activity, ‘aggrecanase’, and antibody BC-4 recognizes the new C-terminus (...DIPEN) generated by the proteolytic action of matrix metalloproteinases. Specificity for these neoepitope sequences was determined in competitive e.l.i.s.a. using synthetic peptide antigens as inhibitors. Antibody BC-3 was used in the detection of aggrecan degradation products in the culture medium obtained from two different in vitro culture systems: bovine cartilage explants treated with either retinoic acid or interleukin-1, and secondly, rat chondrosarcoma cells treated with retinoic acid. Both interleukin-1 and retinoic acid treatment caused an increase in aggrecan catabolism resulting in an increased release to the medium of specific aggrecan degradation products containing the BC-3 neoepitope generated by the action of ‘aggrecanase'. However, several additional aggrecan catabolites were present that were not immunoreactive with antibody BC-3. In addition, under control conditions, in the bovine cartilage cultures the BC-3 epitope was found on some of these aggrecan catabolites. In contrast, no immune-reactive material was found in the aggrecan degradation products present in control media of rat chondrosarcoma cells cultured in the absence of retinoic acid. Collectively, these results demonstrate that ‘aggrecanase’ activity is not a constitutive event in all cartilage culture systems and also suggest that proteolytic agents other than ‘aggrecanase’ are involved in aggrecan catabolism in normal turnover compared with pathological conditions. Antibody BC-4 was used to demonstrate the identity of the G1 domain of aggrecan following proteolytic cleavage of a purified G1-G2 preparation with collagenase, gelatinase A or stromelysin. The G2 product of this cleavage did not react with antibody BC-3, indicating that, under the experimental conditions used, none of these enzymes exhibited ‘aggrecanase’ activity. It is expected that both of these antibodies will play a pivotal role in detailed studies elucidating molecular mechanisms of aggrecan degradation and they will be particularly useful for the sensitive monitoring of aggrecan degradation products in tissue extracts and body fluids.

1998 ◽  
Vol 335 (1) ◽  
pp. 59-66 ◽  
Author(s):  
John D. SANDY ◽  
Dan GAMETT ◽  
Vivian THOMPSON ◽  
Christie VERSCHAREN

A rat chondrosarcoma cell line and bovine cartilage explants have been used to study the control of aggrecan degradation by chondrocytes treated with interleukin-1 (IL-1) or retinoic acid (RA). Aggrecan fragment analysis with anti-neo-epitope antibodies suggests that aggrecanase (an as yet unidentified enzyme) is the only aggrecan-degrading proteinase active in these cultures. With rat cells, aggrecanase converts the aggrecan core protein into two major G1-domain-bearing products (60 kDa with a C-terminal Glu-373, and 220 kDa with a C-terminal Glu-1459). Both products were quantified on a standardized Western analysis system with a G1-specific antibody. Immunoblots were analysed by scanning densitometry and the sensitivity, linearity and reproducibility of the assay were established. With rat cells the aggrecanase response to IL-1 was optimal at about 2 mM glutamine, but was progressively inhibited at higher concentrations, with about 90% inhibition at 10 mM glutamine. Such inhibition by glutamine was not, however, observed with bovine explants. On the other hand, marked inhibition of aggrecanase-dependent cleavage was observed with both rat cells and bovine explants when d(+)-glucosamine was included at concentrations above 2 mM. Inhibition was apparently not due to cytotoxicity or interference with IL-1 signalling, since biosynthetic activity was not inhibited and inhibition of the aggrecanase response was also obtained when RA was used as the catabolic stimulator. Possible mechanisms for the inhibition of the aggrecanase response by glucosamine in chondrocytes treated with IL-1 or RA are discussed.


Blood ◽  
1983 ◽  
Vol 61 (1) ◽  
pp. 171-179 ◽  
Author(s):  
D Ferrero ◽  
S Pessano ◽  
GL Pagliardi ◽  
G Rovera

Abstract The surface changes occurring in three acute myeloid leukemia cell lines (HL60, ML3, and KG1) induced to differentiate by a variety of agents (dimethylsulfoxide, retinoic acid, 12-O-tetradecanoylphorbol-13- acetate, and factors present in lymphocyte conditioned medium) were probed using monoclonal antibodies that are differentiation stage- and lineage-specific. In all cases, the differentiated phenotype was defective and varied with the inducing agent and the cell line used. HL60 proved to be the most sensitive to the effect of the inducers. Retinoic acid was better than DMSO, and TPA was better than the medium factors in the ability to induce granulocytic and monocytic differentiation, respectively, in HL60 cells. These findings indicate that the differentiation block in acute myeloid leukemias is heterogeneous and that each cell line has different phenotypic characteristics that are responsible for the extent of differentiation obtained with a given inducer. These results also suggest that the extent of the differentiation response in vitro may be improved by the use of more suitable inducers for each specific leukemic line.


1987 ◽  
Author(s):  
P W Koppert ◽  
E Hoegee-de Nobel ◽  
W Nieuwenhuizen

We have developed a sandwich-type enzyme immunoassay (EIA) for the quantitation of fibrin degradation products (FbDP) in plasma with a time-to-result of only 45 minutes. The assay is based on the combination of the specificities of two monoclonal antibodies (FDP-14 and DD-13), developed in our institute. FDP-14, the catching antibody, binds both fibrinogen degradation products (FbgDP) and FbDP. It has its epitope in the E-domain of the fibrinogen molecule on the BB-chain between amino acids 54-118 (Blood 68, 437, 1986). Antibody DD-13 was raised using D-dimer as antigen and was used as a tagging antibody, conjugated with horse-radish peroxidase.A strong positive reaction is obtained with a whole blood clot lysate (lysis induced by tissue-type plasminogen activator) which is used as a standard.The EIA does not detect FbgDP i.e. purified fragments X, Y, D:E complexes or FbgDP in plasma treated in vitro with streptokinase. This indicates that the assay is specific for fibrin degradation products.We have successfully applied this assay to the plasma of patients with a variety of diseases. In combination with the assays previously developed by us for FbgDP (Thromb. Haemostas. 1987, in press) and for the total amount (TDP) of FbgDP + FbDP in plasma (J. Lab. Clin. Med. 1987, in press), we are now able to study the composition of TDP in terms of FbgDP and FbDP in patients.


2003 ◽  
Vol 50 (8) ◽  
pp. 418-423 ◽  
Author(s):  
G. Kim ◽  
M. Okumura ◽  
D. Bosnakovski ◽  
T. Ishiguro ◽  
T. Kadosawa ◽  
...  

Blood ◽  
1983 ◽  
Vol 61 (1) ◽  
pp. 171-179 ◽  
Author(s):  
D Ferrero ◽  
S Pessano ◽  
GL Pagliardi ◽  
G Rovera

The surface changes occurring in three acute myeloid leukemia cell lines (HL60, ML3, and KG1) induced to differentiate by a variety of agents (dimethylsulfoxide, retinoic acid, 12-O-tetradecanoylphorbol-13- acetate, and factors present in lymphocyte conditioned medium) were probed using monoclonal antibodies that are differentiation stage- and lineage-specific. In all cases, the differentiated phenotype was defective and varied with the inducing agent and the cell line used. HL60 proved to be the most sensitive to the effect of the inducers. Retinoic acid was better than DMSO, and TPA was better than the medium factors in the ability to induce granulocytic and monocytic differentiation, respectively, in HL60 cells. These findings indicate that the differentiation block in acute myeloid leukemias is heterogeneous and that each cell line has different phenotypic characteristics that are responsible for the extent of differentiation obtained with a given inducer. These results also suggest that the extent of the differentiation response in vitro may be improved by the use of more suitable inducers for each specific leukemic line.


PeerJ ◽  
2019 ◽  
Vol 7 ◽  
pp. e6553
Author(s):  
Puntita Siengdee ◽  
Waranee Pradit ◽  
Siriwadee Chomdej ◽  
Korakot Nganvongpanit

Background Previous studies reported the effect of enrofloxacin (Enro) and marbofloxacin (Mar) on cell death and alteration of the key genes involved in catabolic and anabolic processes and demonstrated the beneficial effects of hyaluronan (HA) combined with fluoroquinolones (FQs) on primary canine chondrocytes. This study further determines the effects of these treatments on canine cartilage explants in both normal and interleukin-1 beta (IL-1β)-stimulated conditions. Methods We examined sulfate glycosaminoglycan (s-GAG) release, uronic acid (UA) content, and safranin-O staining, as well as the expression patterns of inflammatory, extracellular matrix (ECM) component and enzymes. Results Enro treatment alone effectively stimulated proteoglycan anabolism by increasing UA content and glycosaminoglycans (GAGs) in normal and pre-IL-1β-stimulated explant, whereas Mar showed opposite results. The combination of HA and FQs increased s-GAG release and UA content in normal explants in addition to effective down-regulated expression of MMP3. HA reduced the adverse effects of Mar by enhancing UA and GAG contents in both normal and pre-IL-1β-explants. Moreover, HA effectively induced HAS1and ACANup-regulation and reduced MMP9, TNF, PTGS2,and NFKB1 expression for a long term. Discussion Our results suggest the direct effects of Enro and Mar may selectively stimulate the conditioned explants to express MMP-codinggenes and promote gene expression involved in matrix production, pro-inflammatory cytokines, and cell degradation in different directions. HA successfully reduced the adverse effects of FQs by enhancing s-GAG and UA contents and down-regulated expression of MMPs.


Blood ◽  
1998 ◽  
Vol 91 (5) ◽  
pp. 1590-1598 ◽  
Author(s):  
Joan H. Sobel ◽  
Ilya Trakht ◽  
Nicolas Pileggi ◽  
Hong Qi Wu

The fibrinogen αC domain (Aα 220-610) is one of the earliest targets attacked by plasmin following fibrinolytic system activation. Monoclonal antibodies (MoAbs) to defined sequences within the αC domain provide the opportunity to explore the structure-function relationships involved in plasmin's interaction with its Aα chain substrate at greater resolution and can serve as reagents with potential clinical use for detecting fibrinogenolysis in vivo. The MoAb F-104 was raised against a multiple antigenic peptide derivative modelled after the hydrophilic 12-residue sequence corresponding to Aα 487-498 within the αC domain. A sensitive solution phase competitive enzyme-linked immunosorbent assay (ELISA) was developed for MoAb F-104 that can be applied for the direct measurement of intact fibrinogen (purified or plasma; ED50%≈5 pmol Aα chain equivalents/mL), with negligible cross-reactive interference from peptide cleavage products released by plasmin from the COOH-terminal end of the Aα chain (<3%). Immunoblotting and ELISA studies to characterize the fate of the F-104 epitope during fibrinogenolysis in vitro indicated a rapid loss of fibrinogen-associated immunoreactivity that reflected the heterogeneity of plasmin cleavage sites within the αC domain; cleavage at the 493-494 arg-his bond destroyed the F-104 epitope, while cleavage at other sites released it in an altered, inaccessible, conformation within the structure of 35- to 40-kD and 17.5- to 18-kD Aα chain degradation products. Application of the F-104 ELISA to monitor the course of Aα chain proteolysis in a small study population of patients undergoing thrombolytic therapy for myocardial infarction (n = 14) showed that the loss of fibrinogen-associated F-104 immunoreactivity was a very early marker (within 15 to 30 minutes) of in vivo fibrinogenolysis. Additional data obtained suggest that MoAb F-104 may have promise as a reagent for evaluating the creation of an effective lytic state early during therapy, information that could help determine the need for further clinical intervention. Thus, these studies illustrate a rational, targeted, approach towards the development of a novel antifibrinogen MoAb whose application as a structural probe for the region Aα 487-498 in vitro and in vivo can provide new insights into the various molecular forms of fibrinogen that circulate under physiologic conditions and in disease.


1999 ◽  
Vol 23 (3) ◽  
pp. 307-313 ◽  
Author(s):  
J Beattie ◽  
V Borromeo ◽  
S Bramani ◽  
C Secchi ◽  
WR Baumbach ◽  
...  

We describe the properties of three monoclonal antibodies (MAbs) to ovine GH, two of which have previously been shown to enhance, in vivo, the biological activity of bovine and ovine growth hormone. We have examined the effects of these MAbs on GH activity in two appropriate GH-responsive cell culture systems, investigating both acute signalling effects (Janus-activated kinase (Jak)-2 tyrosine phosphorylation -5 min) and longer-term (MTT-formazan production -24 h) effects of hormone-antibody complexes. In the 3T3-F442A pre-adipocyte cell line (which has been demonstrated to be GH responsive), we show that complexation of recombinant bovine (rb) GH with either of the two enhancing anti-ovine GH MAbs (OA11 and OA15) and the non-enhancing MAb, OA14, attenuates the ability of GH to stimulate tyrosine phosphorylation of Jak-2 at a 5-min time point. Using the mouse myeloid cell line, FDC-P1, stably transfected with the full-length ovine GH receptor (oGHR), we demonstrate that rbGH causes a dose-dependent increase in MTT-formazan production by these cells. Further, we demonstrate that OA11 and OA14, but not OA15, cause a decrease in this stimulatory activity of rbGH over a hormone concentration range of 5-50 ng/ml at both 24 and 48 h. We conclude that the different in vitro activities of the two in vivo enhancing MAbs are most probably related to the time-courses over which these two assays are performed, and also to the relative affinities between antibody, hormone and receptor. In addition, the in vitro inhibitory activity of the enhancing MAb OA11 in both short- and long-term bioassay lends further support to an exclusively in vivo model for MAb-mediated enhancement of GH action.


Blood ◽  
1991 ◽  
Vol 77 (8) ◽  
pp. 1829-1836
Author(s):  
RM Lemoli ◽  
C Gasparetto ◽  
DA Scheinberg ◽  
MA Moore ◽  
BD Clarkson ◽  
...  

We report the results of a preclinical study comparing four different purging protocols using a promyelocytic human cell line HL-60 and myeloid leukemic progenitor cells (colony-forming unit-leukemic [CFU- L]) from acute myelogenous leukemia (AML) patients assayed in semisolid culture. We studied the antileukemic effect of (1) Single-cycle complement-mediated lysis by two different monoclonal antibodies (MoAbs) (M195 [CD33] and F23 [CD13] 40 micrograms/mL), reactive with distinct antigens found on early myeloid cells and monocytes, used alone and in combinations; (2) 4-Hydroperoxycyclophosphamide (4-HC) (80 mumol/L or 100 mumol/L) alone; or (3) combined with VP-16 (5 micrograms/mL) and (4) a cocktail of 1 through 3 as above (combined immunochemotherapy). More than 4 logs of HL-60 tumor cell elimination were observed after 1 hour of incubation with both MoAbs plus 4-HC + VP- 16 while the single treatment (immunotherapy or chemotherapy) provided 1.5 and 3.5 logs of colony-forming inhibition, respectively. When the same protocols were tested on cryopreserved leukemic cells from eight patients with AML, we observed a mean value of CFU-L inhibition of 92.3% +/- 2.5% SD, 95.5% +/- 1.4% SD, and 99% +/- 0.8% SD after MoAbs and complement lysis, 4-HC, and 4-HC + VP-16 treatment, respectively. The combined treatment of MoAbs and 4-HC + VP-16 produced more than 3- log reduction of CFU-L colony formation. By comparison, the mean recovery of committed normal bone marrow progenitors after incubation with MoAbs and complement was 12% for CFU-granulocyte-macrophage (CFU- GM), 22.9% for burst-forming unit erythroid (BFU-E), and the recovery following 4-HC + VP-16 treatment was 4.4% for CFU-GM and 5.6% BFU-E. In subsequent experiments, highly purified CD34+ blast cells, enriched by positive selection, and stimulated in liquid culture by cytokines (interleukin-1 [IL-1], IL-3, and combination of both) or MO-conditioned medium (MoCM), demonstrated that immunochemotherapy spares hematopoietic colony-forming cells earlier than day 14 CFU-GM, in vitro.


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