Lysine-Phosphatidylcholine Adducts in Kringle V Impart Unique Immunological and Potential Pro-inflammatory Properties to Human Apolipoprotein(a)

Lipoprotein(a), Lp(a), an athero-thrombotic risk factor, reacts with EO6, a natural monoclonal autoantibody that recognizes the phophorylcholine (PC) group of oxidized phosphatidylcholine (oxPtdPC) either as a lipid or linked by a Schiff base to lysine residues of peptides/proteins. Here we show that EO6 reacts with free apolipoprotein(a) apo(a), its C-terminal domain, F2 (but not the N-terminal F1), kringle V-containing fragments obtained by the enzymatic digestion of apo(a) and also kringle V-containing apo(a) recombinants. The evidence that kringle V is critical for EO6 reactivity is supported by the finding that apo(a) of rhesus monkeys lacking kringle V did not react with EO6. Based on the previously established EO6 specificity requirements, we hypothesized that all or some of the six lysines in human kringle V are involved in Schiff base linkage with oxPtdPC. To test this hypothesis, we made use of a recombinant lysine-containing apo(a) fragment, rIII, containing kringle V but not the protease domain. EO6 reacted with rIII before and after reduction to stabilize the Schiff base and also after extensive ethanol/ether extraction that yielded no lipids. On the other hand, delipidation of the saponified product yielded an average of two mol of phospholipids/mol of protein consistent with direct analysis of inorganic phosphorous on the non-saponified rIII. Moreover, only two of the six theoretical free lysine amino groups per mol of rIII were unavailable to chemical modification by 2,4,6-trinitrobenzene sulfonic acid. Finally, rIII, like human apo(a), stimulated the production of interleukin 8 in THP-1 macrophages in culture. Together, our studies provide evidence that in human apo(a), kringle V is the site that reacts with EO6 via lysine-oxPtdPC adducts that may also be involved in the previously reported pro-inflammatory effect of apo(a) in cultured human macrophages. Lipoprotein(a), Lp(a), an athero-thrombotic risk factor, reacts with EO6, a natural monoclonal autoantibody that recognizes the phophorylcholine (PC) group of oxidized phosphatidylcholine (oxPtdPC) either as a lipid or linked by a Schiff base to lysine residues of peptides/proteins. Here we show that EO6 reacts with free apolipoprotein(a) apo(a), its C-terminal domain, F2 (but not the N-terminal F1), kringle V-containing fragments obtained by the enzymatic digestion of apo(a) and also kringle V-containing apo(a) recombinants. The evidence that kringle V is critical for EO6 reactivity is supported by the finding that apo(a) of rhesus monkeys lacking kringle V did not react with EO6. Based on the previously established EO6 specificity requirements, we hypothesized that all or some of the six lysines in human kringle V are involved in Schiff base linkage with oxPtdPC. To test this hypothesis, we made use of a recombinant lysine-containing apo(a) fragment, rIII, containing kringle V but not the protease domain. EO6 reacted with rIII before and after reduction to stabilize the Schiff base and also after extensive ethanol/ether extraction that yielded no lipids. On the other hand, delipidation of the saponified product yielded an average of two mol of phospholipids/mol of protein consistent with direct analysis of inorganic phosphorous on the non-saponified rIII. Moreover, only two of the six theoretical free lysine amino groups per mol of rIII were unavailable to chemical modification by 2,4,6-trinitrobenzene sulfonic acid. Finally, rIII, like human apo(a), stimulated the production of interleukin 8 in THP-1 macrophages in culture. Together, our studies provide evidence that in human apo(a), kringle V is the site that reacts with EO6 via lysine-oxPtdPC adducts that may also be involved in the previously reported pro-inflammatory effect of apo(a) in cultured human macrophages. Lipoprotein(a) (Lp(a)), 1The abbreviations used are: Lp(a)lipoprotein(a)apo(a)apolipoprotein (a)LDLlow density lipoproteinapoBapolipoproteinBLp(a-)Lp(a) from which apo(a) was removedoxLDLoxidized LDLPtdPCphosphatidylcholineoxPtdPCoxidized phosphatidylcholinePCphosphorylcholinePLphospholipidsPOVPC1-palmitoyl-2-(5′-oxo)valeroyl-sn-glycero-3-phosphorylcholineF1N-terminal fragment of apo(a)F2C-terminal fragment of apo(a)KkringlerIIIrecombinant protein containing the signal peptide, fusion kringles 1 and 5 and kringles 9, 10, and VrK6recombinant protein containing the signal peptide, fusion kringles 1/5, kringles 6–10, V and the protease domainPDprotease domainTNBS2,4,6-trinitrobenzene sulfonic acidIL-8interleukin 8EACAϵ-amino caproic acidDTEdithierythreitolELISAenzyme-linked immunosorbent assayBSAbovine serum albuminPBSphosphate-buffered saline. a recognized risk factor for atherosclerotic cardiovascular disease is made of a lipoprotein particle containing apoB100 linked by a single disulfide bridge to apolipoprotein(a), apo(a), a multikringle structure that varies in size due to differences in the number of kringle (K) type IV-2 repeats. The other kringles, classified from 1 to 10, occur as a single copy each differing in amino acid sequence (1Scanu A.M. Curr. Atheroscler. Reports. 2003; 5: 106-113Crossref PubMed Scopus (46) Google Scholar). The function of some of these kringles has been recognized. For instance, the microdomain comprising KIV-5 through KV-8 has been reported to be involved in the first step of non-covalent interaction between apo(a) and apoB100, and KIV-9 via its unpaired cysteine is responsible for the formation of the disulfide bond that stabilizes the interaction between apo(a) and apoB100 (1Scanu A.M. Curr. Atheroscler. Reports. 2003; 5: 106-113Crossref PubMed Scopus (46) Google Scholar, 2Hobbs H.H. White A.L. Curr. Opin. Lipidol. 1999; 10: 225-236Crossref PubMed Scopus (164) Google Scholar). Moreover, KIV-10 contains the high affinity lysine binding site that plays a dominant role in the binding of apo(a) to fibrin(ogen) and components of the vascular extracellular matrix (3Klezovitch O. Scanu A.M. Atheroscl. Thromb. Vascl. BIol. 1996; Google Scholar). For KV, the reported roles have been an attenuating effect on LDL oxidation (4Hill B.C. Becker L. Anand V. Kusmierczyk A. Marcovina S.M. Rahman M.N. Gabel B.R. Jia Z. Boffa M.B. Koschinsky M.L. Arch. Biochem. Biophys. 2003; 412: 186-195Crossref PubMed Scopus (5) Google Scholar) and stimulation of IL-8 production in human macrophages (5Klezovitch O. Edelstein C. Scanu A.M. J. Biol. Chem. 2001; 276: 46864-46869Abstract Full Text Full Text PDF PubMed Scopus (59) Google Scholar). Of interest, human KV has six lysine residues in contrast with the other kringles that contain no lysine except for KIV-4 and KIV-9 each having one lysine (6Scanu A.M. Edelstein C. Biochim. Biophys. Acta. 1995; 1256: 1-12Crossref PubMed Scopus (61) Google Scholar). lipoprotein(a) apolipoprotein (a) low density lipoprotein apolipoproteinB Lp(a) from which apo(a) was removed oxidized LDL phosphatidylcholine oxidized phosphatidylcholine phosphorylcholine phospholipids 1-palmitoyl-2-(5′-oxo)valeroyl-sn-glycero-3-phosphorylcholine N-terminal fragment of apo(a) C-terminal fragment of apo(a) kringle recombinant protein containing the signal peptide, fusion kringles 1 and 5 and kringles 9, 10, and V recombinant protein containing the signal peptide, fusion kringles 1/5, kringles 6–10, V and the protease domain protease domain 2,4,6-trinitrobenzene sulfonic acid interleukin 8 ϵ-amino caproic acid dithierythreitol enzyme-linked immunosorbent assay bovine serum albumin phosphate-buffered saline. In apo(a), kringles are joined by linkers that vary in size and amino acid sequence and contain O-glycans that account for most of the carbohydrate content of apo(a), about 33% by weight. An exception is the linker between KIV-4 and KIV-5 that contains no carbohydrates and shown to be the preferential site of cleavage by metalloproteinases and leukocyte and pancreatic elastases (7Scanu A.M. Edelstein C. J. Lipid Res. 1997; 38: 2193-2206Abstract Full Text PDF PubMed Google Scholar). Under conditions of limited proteolysis these enzymes cleave apo(a) into two domains, F1 and F2, representing the N- and C-terminal domains, respectively, the latter spanning the region between KIV-5 and the protease domain (PD). F1 and F2 differ markedly in structural properties and function (7Scanu A.M. Edelstein C. J. Lipid Res. 1997; 38: 2193-2206Abstract Full Text PDF PubMed Google Scholar). There has been much recent emphasis on the pro-inflammatory and pro-atherogenic influences of oxidized lipoproteins with particular focus on oxidized LDL (oxLDL) (8Glass C.K. Witztum J.L. Cell. 2001; 104: 503-516Abstract Full Text Full Text PDF PubMed Scopus (2636) Google Scholar). During the oxidation of LDL, many neo-antigenic determinants are generated, which can elicit autoantibody responses. One of these antibodies, which has received a great deal of attention is the monoclonal antibody EO6, an IgM natural antibody cloned from the spleen of apoE-deficient mice (9Palinski W. Hörkkö S. Miller E. Steinbrecher U.P. Powell H.C. Curtiss L.K. Witztum J.L. J. Clin. Invest. 1996; 98: 800-814Crossref PubMed Scopus (501) Google Scholar) along with several other such antibodies, recognizes predominantly the phosphorylcholine (PC) moiety of oxidized phosphatidylcholine (oxPtdPC) but not the PC of unoxidized PtdPC. EO6 recognizes oxidized PtdPC present in the lipid moiety of oxLDL, as well as when the oxidized phospholipids (PL) is covalently attached to apoB of oxLDL. In the latter situation, the oxidized PtdPC is linked to the ϵ amino group of lysine of apoB via a Schiff base with the aldehyde derived from the sn-2 fatty acid of oxPtdPC (10Hörkkö B., D.A. Miller E. Itabe H. Leitinger N. Subbanagounder G. Berliner J.A. Friedman P. Dennis E.A. Curtiss L.K. Palinski W. Witztum J.L. J. Clin. Invest. 1999; 103: 117-128Crossref PubMed Scopus (472) Google Scholar, 11Gillotte K.L. Hörkkö S. Witztum J.L. Steinberg D. J. Lipid Res. 2000; 41: 824-833Abstract Full Text Full Text PDF PubMed Google Scholar, 12Friedman P. Hörkkö S. Steinberg D. Witztum J.L. J. Biol. Chem. 2002; 277: 7010-7020Abstract Full Text Full Text PDF PubMed Scopus (180) Google Scholar). EO6 binds not only to oxLDL but oxidized epitopes in sites of inflammation most notably the atherosclerotic plaque (13Witztum J.L. Steinberg D. Trends Cardiovasc. Med. 2001; 11: 93-102Crossref PubMed Scopus (388) Google Scholar). In human plasma, EO6 has been shown to specifically react with epitopes on Lp(a) (14Tsimikas S. Bergmark C. Beyer R.W. Patel R. Pattison J. Miller E. Juliano J. Witztum J.L. J. Am. Coll. 2003; 41: PubMed Scopus Google Scholar). to the and of the in Lp(a) and the of lysines in For this we used of human Lp(a), apo(a), rhesus apo(a), and apo(a) and EO6 reactivity by and The of these studies are the of this leukocyte pancreatic acid acid and from were from were from and an from were obtained from and were of low to of apo(a), Lp(a), and LDL were in the and to apo(a), Lp(a) and LDL were as previously M.L. Scanu A.M. J. Lipid Res. Full Text PDF PubMed Google Scholar). was shown to be of to LDL and was to The monoclonal KV antibody was as previously C. Scanu A.M. J. Biol. Chem. 1997; Full Text Full Text PDF PubMed Scopus Google Scholar). EO6 was as previously (9Palinski W. Hörkkö S. Miller E. Steinbrecher U.P. Powell H.C. Curtiss L.K. Witztum J.L. J. Clin. Invest. 1996; 98: 800-814Crossref PubMed Scopus (501) Google Scholar). other were of of Lp(a), and having a single apo(a) with type kringles, KV and the protease domain, was from the of a by and as previously M.L. R. PubMed Scopus Google Scholar). was from the Lp(a) conditions with as previously C. D. Scanu A.M. 1995; PubMed Scopus Google Scholar). was the LDL after reduction of Lp(a) with and was to be free of LDL was from the by PubMed Scopus Google Scholar). The were by and and shown not to be by apoB100 and of Lp(a) and was from rhesus as previously A.M. D. J. E. J.L. J. Clin. Invest. PubMed Scopus Google Scholar). apo(a) was from Lp(a) as for the human of was as previously K.L. Hörkkö S. Witztum J.L. Steinberg D. J. Lipid Res. 2000; 41: 824-833Abstract Full Text Full Text PDF PubMed Google Scholar). LDL The oxidation was in in the of and of with for The of the was by the of fatty a and by and of of the apo(a) fragments obtained by limited proteolysis either human leukocyte or pancreatic is in The digestion of Lp(a) and the of the fragments was as previously (5Klezovitch O. Edelstein C. Scanu A.M. J. Biol. Chem. 2001; 276: 46864-46869Abstract Full Text Full Text PDF PubMed Scopus (59) Google Scholar). The of the fragments was by on and by analysis and as well as monoclonal In N-terminal sequence analysis of the first amino the and of each the studies involved only F1 and F2, these fragments were by limited digestion of apo(a) with pancreatic as previously by Edelstein C. J.A. O. Scanu A.M. J. Lipid Res. 1996; Full Text PDF PubMed Google Scholar). The fragments were in containing and of was cloned into a by a as and by N. O. A.M. J. Lipid Res. Full Text Full Text PDF PubMed Google Scholar). contains the signal a fusion kringle from and from by of apo(a) sequence containing single of through KV and a protease domain, The signal sequence was in to of the recombinant protein into the The rIII recombinant lacking 8 and was by the with and the was to digestion with in to the for apo(a) through The and the fragments were into the with and the and the rIII were into human and the of recombinant of the were by of were from apo(a) for 8 with The apo(a) was to a extraction with for by of reduction of Lp(a) and apo(a), its derived fragments and the was by a previously with K.L. Hörkkö S. Witztum J.L. Steinberg D. J. Lipid Res. 2000; 41: 824-833Abstract Full Text Full Text PDF PubMed Google Scholar). Lp(a), apo(a), and present in were with a of for The was by extensive Under these Schiff base adducts are to was on and apo(a) and rIII by with 1 for 1 was to a of the of apo(a) and rIII was in 5 for The was with 1 and by or of was on a for as previously C. J.A. O. Scanu A.M. J. Lipid Res. 1996; Full Text PDF PubMed Google Scholar). or of were for in after the were which were previously with a containing was on a for for and for the were in containing and by with or the were with the to the of oxidized with the IgM monoclonal antibody EO6 was by first the with for 1 by for with EO6 in after the were as except that IgM were such as or a and not be and protein were by a as previously M.L. Scanu A.M. J. Lipid Res. Full Text PDF PubMed Google Scholar) except that was used as the antibody and to as the For the of apo(a), to was used as the for of oxidized phospholipids to was by the EO6 in lipoproteins and the derived apo(a) and fragments as previously (10Hörkkö B., D.A. Miller E. Itabe H. Leitinger N. Subbanagounder G. Berliner J.A. Friedman P. Dennis E.A. Curtiss L.K. Palinski W. Witztum J.L. J. Clin. Invest. 1999; 103: 117-128Crossref PubMed Scopus (472) Google Scholar, 11Gillotte K.L. Hörkkö S. Witztum J.L. Steinberg D. J. Lipid Res. 2000; 41: 824-833Abstract Full Text Full Text PDF PubMed Google Scholar, 12Friedman P. Hörkkö S. Steinberg D. Witztum J.L. J. Biol. Chem. 2002; 277: 7010-7020Abstract Full Text Full Text PDF PubMed Scopus (180) Google Scholar). were for in a were in and the as per number of free amino groups was by reactivity with as previously with K.L. Hörkkö S. Witztum J.L. Steinberg D. J. Lipid Res. 2000; 41: 824-833Abstract Full Text Full Text PDF PubMed Google Scholar). first with and were to in and of in the was and for 1 of and of 1 were and for was and the of was from of used as a on THP-1 in conditions were previously (5Klezovitch O. Edelstein C. Scanu A.M. J. Biol. Chem. 2001; 276: 46864-46869Abstract Full Text Full Text PDF PubMed Scopus (59) Google Scholar). the human obtained from was in bovine and and were in a density of 1 and in the in the of for in and a for the were to of apo(a) or rIII for the of the the of IL-8 in the was by to the the were in The content of apo(a) and rIII, was by the The of for was of phosphorous was the by J. Biol. Chem. Full Text PDF PubMed Google Scholar) by first the with for were obtained by the inorganic by were by the protein assay as a The EO6 in human EO6 reacts with Lp(a) (14Tsimikas S. Bergmark C. Beyer R.W. Patel R. Pattison J. Miller E. Juliano J. Witztum J.L. J. Am. Coll. 2003; 41: PubMed Scopus Google Scholar). To the EO6 of the we of on Lp(a), apo(a), and LDL from the Lp(a) and apo(a) were EO6 as well as oxLDL, used as a In LDL and were Of the with EO6 the of apo(a), and an of a high of epitopes in the In the the was to the of kringle containing an unpaired of differences in the in the EO6 a of apo(a) in the The of the was by the that a of 5 of apo(a) the conditions of in the of not The EO6 in the C-terminal of the EO6 apo(a) was to limited proteolysis by pancreatic In with C. J.A. O. Scanu A.M. J. Lipid Res. 1996; Full Text PDF PubMed Google this two and F2, representing the N- and C-terminal domains, of EO6 only F2 for apo(a) in the of F2 for EO6 was 5 and were also The EO6 in the of these studies we apo(a) to a extensive digestion by leukocyte and the fragments were to (5Klezovitch O. Edelstein C. Scanu A.M. J. Biol. Chem. 2001; 276: 46864-46869Abstract Full Text Full Text PDF PubMed Scopus (59) Google Scholar). Of only reacted with EO6 as with the of reactivity by and through The of for can be by the that kringle containing the free The in were in a direct binding assay was by by be due to due to its on apo(a) KV the J. J. R. J. Biol. Chem. Full Text PDF PubMed Google Scholar). analysis and rhesus apo(a) did not react with EO6. is consistent with the that KV of apo(a) is responsible for the EO6 reactivity on with these studies we to the on KV obtained with natural also to apo(a) recombinants. For this we used two and rIII that have been in two the signal peptide, the fusion kringles 1/5, KIV-10 and KV but not the and rIII reacted with EO6 by and that KV is the 1/5, KIV-9 and KIV-10 are as the site on the in that only of the fragments and is be that on the due to the high on the were present in the obtained evidence that KV is the EO6 site in apo(a), we our attention to the lysine residues on the that EO6 binds to the PC group of oxidized phospholipids that are covalently to lysines of or by a Schiff base between the aldehyde of oxPtdPC and the amino group of the lysine K.L. Hörkkö S. Witztum J.L. Steinberg D. J. Lipid Res. 2000; 41: 824-833Abstract Full Text Full Text PDF PubMed Google Scholar, 12Friedman P. Hörkkö S. Steinberg D. Witztum J.L. J. Biol. Chem. 2002; 277: 7010-7020Abstract Full Text Full Text PDF PubMed Scopus (180) Google Scholar). In to stabilize Schiff present we apo(a) and rIII with to a and a two the EO6 reactivity as in and EO6 reactivity on the to analysis in the of a of PC containing with the fragments of In these studies we to were in apo(a) and in rIII of a first we apo(a) and rIII to an extensive delipidation with ethanol/ether by all non-covalent lipids. The from each no as by the apo(a) and rIII in and the EO6 reactivity as the product as by and by a we a between and The of oxidized to the apo(a) is via a fatty aldehyde in the sn-2 linked via a Schiff base to the lysine of the of this the fatty acid and fatty aldehyde from the which be The Schiff base is to such apo(a) and rIII were saponified with 1 and to with by an ethanol/ether extraction as The saponified no and also to react with EO6 The mol and mol of apo(a) and rIII, Friedman P. Hörkkö S. Steinberg D. Witztum J.L. J. Biol. Chem. 2002; 277: 7010-7020Abstract Full Text Full Text PDF PubMed Scopus (180) Google Scholar) have shown that the PC group of was for EO6 and that oxidized containing other groups such as or did not EO6 Based on this we apo(a) and rIII with an that specifically recognizes PtdPC. The in show that after EO6 reactivity was no the that and in PC as of an oxPtdPC are covalently attached to and that are critical for EO6 in lysine residues involved in interaction with oxPtdPC an that reduction with a of free the number of amino groups not linked to oxPtdPC. Based on the reactivity of with we that were an average of mol of of protein involved in that this well with the of about mol of apo(a) by previously that apo(a) the of IL-8 from THP-1 macrophages (5Klezovitch O. Edelstein C. Scanu A.M. J. Biol. Chem. 2001; 276: 46864-46869Abstract Full Text Full Text PDF PubMed Scopus (59) Google Scholar). In the we the effect of rIII with that of shown in apo(a) and rIII stimulated IL-8 rIII was apo(a) and rIII contain a single copy of KV and mol of of protein that these have been responsible for the is supported by our finding that apo(a) fragments and that KV and are EO6 not IL-8 the a in the of between apo(a) and rIII, a by is in with our finding that F2, the C-terminal fragment of apo(a), a production and of IL-8 the apo(a) (5Klezovitch O. Edelstein C. Scanu A.M. J. Biol. Chem. 2001; 276: 46864-46869Abstract Full Text Full Text PDF PubMed Scopus (59) Google Scholar). The studies have shown that KV is a critical in the of apo(a) by EO6, an autoantibody shown to react with oxPtdPC either in its free or linked by a Schiff base to lysine residues of or The role of KV in this is supported by the that only either natural or reacted with EO6 and by the of reactivity in rhesus apo(a) that In human apo(a), KV contains lysines in contrast to the other kringles that are except for the single lysine in KIV-9 and the latter kringle in the F1 domain that we show not react with EO6. amino group we also that only of the six lysines in KV reacted with the that the other two were covalently by a Schiff base to oxPtdPC. is supported by the that two mol protein be from either apo(a) or rIII only after and that such extraction these two to EO6 Moreover, reactivity was also cleavage of these by C. EO6 not react with containing or this that the the PC In the the derived from the chemical that only two of the six lysines in KV were involved in formation received from a that the of and as the for linkage with this on of and on the KV to of these is in with and be that only mol of were the of an apo(a) with a of as a The finding that a recombinant product by human reacted with EO6, like the apo(a) from human plasma, that modification of the lysines of KV can occur in other the and not the of an EO6 reacts with 1-palmitoyl-2-(5′-oxo)valeroyl-sn-glycero-3-phosphorylcholine and P. Hörkkö S. Steinberg D. Witztum J.L. J. Biol. Chem. 2002; 277: 7010-7020Abstract Full Text Full Text PDF PubMed Scopus (180) Google Scholar). to the that apo(a) is to to oxPtdPC of is made in the and to covalently to LDL, the of from the H.H. White A.L. Curr. Opin. Lipidol. 1999; 10: 225-236Crossref PubMed Scopus (164) Google Scholar). we that in apo(a) may from LDL, we the as a of LDL, apoB reacts with EO6. on the made in apo(a) LDL from oxidation (4Hill B.C. Becker L. Anand V. Kusmierczyk A. Marcovina S.M. Rahman M.N. Gabel B.R. Jia Z. Boffa M.B. Koschinsky M.L. Arch. Biochem. Biophys. 2003; 412: 186-195Crossref PubMed Scopus (5) Google Scholar, W. G. H. Biochim. Biophys. Acta. PubMed Scopus Google Scholar, C. D. Scanu A.M. Thromb. Biol. 2001; Scholar). Lp(a) has a of factor LDL C. A. J. Biol. Chem. 1995; Full Text Full Text PDF PubMed Scopus Google a that a of oxPtdPC. to this the of in apo(a) be on to to the lysines in be in with the of apo(a), its of binding to Scanu A.M. J. Biol. Chem. Full Text PDF Google Scholar) and the high between of Lp(a) and EO6 reactivity (14Tsimikas S. Bergmark C. Beyer R.W. Patel R. Pattison J. Miller E. Juliano J. Witztum J.L. J. Am. Coll. 2003; 41: PubMed Scopus Google Scholar). these be to the number of lysines in KV modification may vary as a function of the oxPtdPC in its be that these studies have only the of EO6 reactivity to the apo(a) of the that some EO6 reactivity may be in the lipid of the The of the oxPtdPC adducts in human apo(a) is the cardiovascular have been to the of Lp(a) and in apo(a) have been for each reported function (1Scanu A.M. Curr. Atheroscler. Reports. 2003; 5: 106-113Crossref PubMed Scopus (46) Google Scholar). we have shown that apo(a), its C-terminal domain and one of the fragments comprising the region stimulated the production and of IL-8 in human THP-1 macrophages in (5Klezovitch O. Edelstein C. Scanu A.M. J. Biol. Chem. 2001; 276: 46864-46869Abstract Full Text Full Text PDF PubMed Scopus (59) Google Scholar). In studies we also that IL-8 stimulation was in the of a monoclonal antibody for In the we show that recombinant rIII that contains KV but not also IL-8 that KV may be the in the and that oxPtdPC adducts may have a into that oxPtdPC by has a pro-inflammatory function N. S. A.L. Berliner J.A. J. Biol. Chem. 2003; Full Text Full Text PDF PubMed Scopus Google Scholar). the to the that can apo(a) to are on a of an our studies have in KV an between and pro-inflammatory that along with the previously (1Scanu A.M. Curr. Atheroscler. Reports. 2003; 5: 106-113Crossref PubMed Scopus (46) Google Scholar) may a role in the cardiovascular of In the of our we to the that other components of apo(a) may the of the lysines of KV for formation with have a to this in the reactivity of with EO6 with rIII is to this from the for of rhesus