title: CD13 Autoantibodies Are Elevated in Sera From Mothers of Infants With Neonatal Cholestasis of Different Causes.
abstract: Human cytomegalovirus (HCMV) infection induces production of CD13-specific autoantibodies, which may promote inflammation and tissue damage. HCMV infection has been suggested as a cause of biliary atresia (BA), but little is known of its role in other forms of neonatal cholestasis. We studied serum levels of CD13-specific autoantibodies in mothers of infants with neonatal cholestasis of different causes, including BA, and in mothers of healthy, term infants without cholestasis, as well as in healthy blood donors.
  
  
  
  Using fluorescence-activated cell sorting, we measured CD13-specific autoantibody levels in serum from the above-mentioned groups. In addition, the effect of serum from mothers of infants with neonatal cholestasis was tested on the differentiation of monocytes into macrophages.
  
  
  
  CD13-specific autoantibodies were found in mothers of infants with neonatal cholestasis, but not in mothers of infants without cholestasis and healthy blood donors, and were associated with HCMV seropositivity. Sera from mothers of infants with all forms of neonatal cholestasis inhibited differentiation of monocytes into macrophages, but this was not dependent on CD13-specific autoantibodies.
  
  
  
  The significantly higher frequency of CD13-specific autoantibodies in mothers of infants with neonatal cholestasis of all forms compared with mothers of healthy infants without cholestasis suggests an association, but does not prove that they are pathogenic. The presence of CD13-specific autoantibodies does not correlate with HCMV IgG serostatus, suggesting a more complicated mechanism that possibly reflects active HCMV infection in these individuals. Further studies are needed to elucidate whether these autoantibodies contribute to the development of cholestasis or represent an epiphenomenon.
authors.affiliation: *Department of Medicine Solna, Experimental Cardiovascular Research Unit, Center for Molecular Medicine, Karolinska Institutet †Department of Rheumatology ‡Division of Pediatrics, CLINTEC, Karolinska Institutet, Astrid Lindgren Children's Hospital, Karolinska University Hospital, Stockholm, Sweden.
authors.forename: Xinling
authors.initials: X
authors.lastname: Xu
authors.forename: Afsar
authors.initials: A
authors.lastname: Rahbar
authors.forename: Soley
authors.initials: S
authors.lastname: Omarsdottir
authors.forename: Jonas
authors.initials: J
authors.lastname: Teng
authors.forename: Antal
authors.initials: A
authors.lastname: Németh
authors.forename: Björn
authors.initials: B
authors.lastname: Fischler
authors.forename: Cecilia
authors.initials: C
authors.lastname: Söderberg-Nauclér
mesh_terms: D000328:Adult; D000818:Animals; D001323:Autoantibodies / Q000097:blood*; D001656:Biliary Atresia / Q000097:blood / Q000209:etiology; D018826:CD13 Antigens; D002779:Cholestasis / Q000097:blood* / Q000209:etiology; D003587:Cytomegalovirus; D003586:Cytomegalovirus Infections / Q000097:blood* / Q000150:complications / Q000821:virology; D005260:Female; D006801:Humans; D007074:Immunoglobulin G / Q000097:blood; D007231:Infant, Newborn; D007232:Infant, Newborn, Diseases / Q000097:blood* / Q000209:etiology; D008107:Liver Diseases / Q000097:blood / Q000209:etiology; D051379:Mice; D009000:Monocytes; D009035:Mothers; D041681:NIH 3T3 Cells; D011247:Pregnancy; D011251:Pregnancy Complications, Infectious / Q000097:blood / Q000821:virology; D055815:Young Adult
chemical_list: D001323:Autoantibodies; D007074:Immunoglobulin G; D018826:CD13 Antigens