title: The intravenous injection of oxidized LDL- or Apolipoprotein B100--Coupled splenocytes promotes Th1 polarization in wildtype and Apolipoprotein E--Deficient mice.
abstract: BACKGROUND
  Th1 responses in atherosclerosis are mainly associated with the aggravation of atherosclerotic plaques, whereas Th2 responses lead to a less pronounced disease in mouse models. The fixation of antigens on cells by means of ethylene carbodiimide (ECDI), and subsequent injection of these antigen-coupled splenocytes (Ag-SP) to induce tolerance against the attached antigens, has been successfully used to treat murine type 1 diabetes or encephalomyelitis in. We analyzed this approach in a mouse model for atherosclerosis.
  
  
  RESULTS
  OTII-transgenic mice that were treated with a single dose of 5 × 10(7) OVA-coupled splenocytes (OVA-SP), had decreased splenocyte proliferation, and lower IFNγ production in vitro upon antigen recall. However, in vivo CD4 cell activation was increased. To try lipoprotein-derived, "atherosclerosis-associated" antigens, we first tested human oxidized LDL. In wild type mice, an increase of IFNγ production upon in vitro recall was detected in the oxLDL-SP group. In Apolipoprotein E - deficient (ApoE-/-) mice that received oxLDL-SP every 5 weeks for 20 weeks, we did not find any difference of atherosclerotic plaque burden, but again increased IFNγ production. To overcome xenogenous limitations, we then examined the effects of mouse Apolipoprotein B100 peptides P3 and P6. ApoB100-SP treatment again promoted a more IFNγ pronounced response upon in vitro recall. Flow cytometry analysis of cytokine secreting spleen cells revealed CD4 positive T cells to be mainly the source for IFNγ. In ApoE-/- mice that were administered ApoB100-SP during 20 weeks, the atherosclerotic plaque burden in aortic roots as well as total aorta was unchanged compared to PBS treated controls. Splenocyte proliferation upon antigen recall was not significantly altered in ApoB100-SP treated ApoE-/- mice.
  
  
  CONCLUSIONS
  Although we did not observe a relevant anti-atherosclerotic benefit, the treatment with antigen-coupled splenocytes in its present form already impacts the immune responses and deserves further exploration.
authors.affiliation: INSERM, Unit 970, Paris Cardiovascular Research Center, 75015 Paris, France; Internal Medicine II, University Hospital Bonn, 53105 Bonn, Germany. Electronic address: martin.steinmetz@ukb.uni-bonn.de.
authors.forename: Martin
authors.initials: M
authors.lastname: Steinmetz
authors.affiliation: INSERM, Unit 970, Paris Cardiovascular Research Center, 75015 Paris, France.
authors.forename: Padmapriya
authors.initials: P
authors.lastname: Ponnuswamy
authors.affiliation: INSERM, Unit 970, Paris Cardiovascular Research Center, 75015 Paris, France.
authors.forename: Ludivine
authors.initials: L
authors.lastname: Laurans
authors.affiliation: INSERM, Unit 970, Paris Cardiovascular Research Center, 75015 Paris, France.
authors.forename: Bruno
authors.initials: B
authors.lastname: Esposito
authors.affiliation: INSERM, Unit 970, Paris Cardiovascular Research Center, 75015 Paris, France.
authors.forename: Alain
authors.initials: A
authors.lastname: Tedgui
authors.affiliation: INSERM, Unit 970, Paris Cardiovascular Research Center, 75015 Paris, France; Division of Cardiovascular Medicine, University of Cambridge, Addenbrooke's Hospital, Cambridge, CB2 2QQ, UK.
authors.forename: Ziad
authors.initials: Z
authors.lastname: Mallat
mesh_terms: D000818:Animals; D053299:Apolipoprotein B-100 / Q000737:chemistry / Q000276:immunology*; D001057:Apolipoproteins E / Q000172:deficiency* / Q000235:genetics / Q000276:immunology; D050197:Atherosclerosis / Q000235:genetics / Q000276:immunology / Q000473:pathology / Q000628:therapy*; D002234:Carbodiimides / Q000737:chemistry; D064987:Cell- and Tissue-Based Therapy; D004195:Disease Models, Animal; D005260:Female; D015870:Gene Expression; D006801:Humans; D007275:Injections, Intravenous; D007371:Interferon-gamma / Q000096:biosynthesis / Q000378:metabolism; D008077:Lipoproteins, LDL / Q000737:chemistry / Q000276:immunology*; D017710:Lymphocyte Transfusion; D008214:Lymphocytes / Q000737:chemistry / Q000276:immunology; D008264:Macrophages / Q000737:chemistry / Q000276:immunology / Q000637:transplantation; D008297:Male; D051379:Mice; D018345:Mice, Knockout; D009000:Monocytes / Q000737:chemistry / Q000276:immunology / Q000637:transplantation; D058226:Plaque, Atherosclerotic / Q000235:genetics / Q000276:immunology / Q000473:pathology / Q000628:therapy*; D013154:Spleen / Q000166:cytology / Q000276:immunology; D018417:Th1 Cells / Q000276:immunology / Q000473:pathology; D017211:Treatment Failure
chemical_list: D053299:Apolipoprotein B-100; D001057:Apolipoproteins E; D002234:Carbodiimides; D008077:Lipoproteins, LDL; C099252:oxidized low density lipoprotein; D007371:Interferon-gamma
keywords: Apolipoprotein B100; Apolipoprotein E deficient mice; Atherosclerosis; ECDI; Immunization; LDL