title: HSV IgG antibody inhibits virus detection in CSF.
abstract: BACKGROUND
  Before PCR testing of cerebrospinal fluid (CSF), laboratory diagnosis of herpes encephalitis (HSE) was based on virus isolation from brain biopsy. Viral isolation from CSF has limited clinical value due to low virus recovery; the cause for which has not been demonstrated.
  
  
  OBJECTIVE
  To investigate the role of anti-HSV antibodies on recovery of HSV from CSF via cell culture.
  
  
  METHODS
  HSV-positive CSF samples were evaluated for their ability to neutralize HSV in cell culture. The presence of HSV-specific IgG and IgM antibodies were analyzed using HSV-infected cells. To identify whether HSV-specific IgG is the cause of viral inhibition, IgG was removed using anti-human IgG magnetic beads. Viral inhibition from CSF originating from asymptomatic patients was examined as a comparison.
  
  
  RESULTS
  CSF from 13 patients with acute HSV CNS disease was analyzed. All displayed high levels of viral neutralization to both HSV-1 and HSV-2 regardless of the infecting subtype. Interestingly, all the CSF samples stained strongly for anti-IgG antibody but none for anti-IgM antibody. Removal of IgG from CSF eliminated the viral inhibitory activity. Neutralizing IgG antibody was also found to be common in CSF of most patients, even in the absence of HSV disease.
  
  
  CONCLUSIONS
  Viral specific IgG is the major determinant of viral inhibition in CSF and prevents virus recovery in cell culture. In CSF from HSE un-infected patients, viral inhibitory IgG originates from circulating serum antibody and is commonly present in CSF. However, this inhibitory IgG is not protective for the development of HSV disease.
authors: Case Western Reserve University, Cleveland, OH 44106-7219, United States. stacy.fening@case.edu
authors: Stacy Weber
authors: SW
authors: Fening
authors: Frank
authors: F
authors: Esper
authors: David
authors: D
authors: Scholl
authors: Yung T
authors: YT
authors: Huang
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000914:Antibodies, Viral / Q000134:cerebrospinal fluid*; D002555:Cerebrospinal Fluid / Q000276:immunology* / Q000821:virology*; D002648:Child; D002675:Child, Preschool; D020803:Encephalitis, Herpes Simplex / Q000175:diagnosis* / Q000276:immunology / Q000821:virology; D005260:Female; D018259:Herpesvirus 1, Human / Q000276:immunology / Q000302:isolation & purification*; D006801:Humans; D007074:Immunoglobulin G / Q000134:cerebrospinal fluid*; D007223:Infant; D007231:Infant, Newborn; D008297:Male; D008875:Middle Aged; D012680:Sensitivity and Specificity; D014776:Virus Cultivation / Q000379:methods; D055815:Young Adult
chemical_list: D000914:Antibodies, Viral; D007074:Immunoglobulin G