title: Discrepancy in CCL2 and CCR2 expression in white versus grey matter hippocampal lesions of Multiple Sclerosis patients.
abstract: A remarkable pathological difference between grey matter lesions (GML) and white matter lesions (WML) in Multiple Sclerosis (MS) patients is the paucity of infiltrating leukocytes in GML. To better understand these pathological differences, we hypothesize that the chemokine monocyte chemotactic protein-1 (MCP-1 or CCL2), of importance for leukocyte migration, and its receptor CCR2 are more abundantly expressed in WML than in GML of MS patients. To this end, we analyzed CCL2 and CCR2 expression in the hippocampus, comprising WML and GML,of post-mortem MS patients, and of control subjects. CCL2 and CCR2 mRNA were significantly increased in demyelinated MS hippocampus. Semi-quantification of CCL2 and CCR2 immunoreactivity showed that CCL2 is present in astrocytes only in active WML. CCR2 is upregulated in monocytes/macrophages or amoeboid microglia in active WML, and in ramified microglia in active GML, although to a lesser extent. As a follow-up, we observed a significantly increased CCL2 production by WM-, but not GM-derived astrocytes upon stimulation with bz-ATP in vitro. Finally, upon CCL2 stimulation, GM-derived microglia significantly increased their proliferation rate. We conclude that within hippocampal lesions, CCL2 expression is mainly restricted to WML, whereas the receptor CCR2 is upregulated in both WML and GML. The relative absence of CCL2 in GML may explain the lack of infiltrating immune cells in this type of lesions. We propose that the divergent expression of CCL2 and CCR2 in WML and GML explains or contributes to the differences in WML and GML formation in MS.
authors.forename: Marloes
authors.initials: M
authors.lastname: Prins
authors.forename: Ranjan
authors.initials: R
authors.lastname: Dutta
authors.forename: Bart
authors.initials: B
authors.lastname: Baselmans
authors.forename: John J P
authors.initials: JJ
authors.lastname: Brevé
authors.forename: John G J M
authors.initials: JG
authors.lastname: Bol
authors.forename: Sadie A
authors.initials: SA
authors.lastname: Deckard
authors.forename: Paul
authors.initials: P
authors.lastname: van der Valk
authors.forename: Sandra
authors.initials: S
authors.lastname: Amor
authors.forename: Bruce D
authors.initials: BD
authors.lastname: Trapp
authors.forename: Helga E
authors.initials: HE
authors.lastname: de Vries
authors.forename: Benjamin
authors.initials: B
authors.lastname: Drukarch
authors.forename: Anne-Marie
authors.initials: AM
authors.lastname: van Dam
mesh_terms: D000255:Adenosine Triphosphate / Q000031:analogs & derivatives / Q000494:pharmacology; D000328:Adult; D000368:Aged; D000818:Animals; D000831:Animals, Newborn; D001973:Bromodeoxyuridine / Q000378:metabolism; D049109:Cell Proliferation / Q000187:drug effects / Q000235:genetics; D002478:Cells, Cultured; D018932:Chemokine CCL2 / Q000235:genetics* / Q000378:metabolism; D005260:Female; D015870:Gene Expression / Q000187:drug effects; D066128:Gray Matter / Q000378:metabolism*; D006624:Hippocampus / Q000473:pathology*; D000949:Histocompatibility Antigens Class II / Q000378:metabolism; D006801:Humans; D008297:Male; D008875:Middle Aged; D009103:Multiple Sclerosis / Q000473:pathology*; D004676:Myelin Basic Protein / Q000235:genetics / Q000378:metabolism; D009457:Neuroglia / Q000378:metabolism; D010975:Platelet Aggregation Inhibitors / Q000494:pharmacology; D051381:Rats; D017208:Rats, Wistar; D054390:Receptors, CCR2 / Q000235:genetics* / Q000378:metabolism; D066127:White Matter / Q000378:metabolism*
chemical_list: C111835:CCL2 protein, human; C515334:CCR2 protein, human; D018932:Chemokine CCL2; D000949:Histocompatibility Antigens Class II; D004676:Myelin Basic Protein; D010975:Platelet Aggregation Inhibitors; D054390:Receptors, CCR2; C033901:3'-O-(4-benzoyl)benzoyladenosine 5'-triphosphate; D000255:Adenosine Triphosphate; D001973:Bromodeoxyuridine