title: Beta amyloid precursor protein and patterns of HIV p24 immunohistochemistry in different brain areas of AIDS patients.
abstract: OBJECTIVE
  To evaluate the correlation between immunohistochemical positive patterns (globular and filamentous structures) of beta-amyloid precursor protein (beta-APP), used as a marker of axonal damage, and the different distribution of HIV p24 antigens, in three different brain areas of AIDS patients.
  
  
  METHODS
  Eighteen AIDS patients with HIV-related brain lesions were included in the study. Forty-nine sections from basal ganglia, frontal cortex and hippocampus were selected. After microwave oven pre-treatment, the sections were incubated with anti-HIV p24 and anti-beta-APP monoclonal antibodies; the reactions were developed with peroxidase/3,3'diaminobenzidine. The positivity was graded by semi-quantitative scores. Double immunohistochemical staining was used to evaluate the co-localization of the antigens.
  
  
  RESULTS
  HIV p24 immunohistochemistry was positive in 44 of 49 sections (89%), with a prevalence of interstitial positive cells and positive microglial nodules in 27 and 13 sections respectively. beta-APP-positive structures were demonstrated in 23 of 44 sections (52%) with HIV-related lesions, and were absent from the five sections without viral expression. Globular and filamentous lesions were observed in 21 of 23 sections and 10 of 23 lesions respectively. Moreover, a high grade of globular type lesion was related to an elevated presence of diffuse interstitial HIV p24-positive cells in basal ganglia; double immunohistochemical reactions demonstrated the co-localization of beta-APP globules and HIV p24 antigens.
  
  
  CONCLUSIONS
  The data obtained confirm the coexpression of beta-APP and viral antigens in particular areas of the brain with HIV-related lesions; there is a strict correlation between beta-APP globules (indicating chronic cerebral damage) and the interstitial pattern of HIV p24 immunohistochemistry.
authors.affiliation: Pathology Unit, 'Ospedale Civile', Vimercate, the Pathologhy Unit, 'L. Sacco' Institute of Medical Science, University of Milan, Italy.
authors.forename: M
authors.initials: M
authors.lastname: Nebuloni
authors.forename: A
authors.initials: A
authors.lastname: Pellegrinelli
authors.forename: A
authors.initials: A
authors.lastname: Ferri
authors.forename: S
authors.initials: S
authors.lastname: Bonetto
authors.forename: R
authors.initials: R
authors.lastname: Boldorini
authors.forename: L
authors.initials: L
authors.lastname: Vago
authors.forename: M P
authors.initials: MP
authors.lastname: Grassi
authors.forename: G
authors.initials: G
authors.lastname: Costanzi
mesh_terms: D000163:Acquired Immunodeficiency Syndrome / Q000453:epidemiology / Q000378:metabolism* / Q000473:pathology / Q000821:virology; D016564:Amyloid beta-Protein Precursor / Q000378:metabolism*; D001479:Basal Ganglia / Q000378:metabolism* / Q000473:pathology / Q000821:virology; D015415:Biomarkers; D005625:Frontal Lobe / Q000378:metabolism* / Q000473:pathology / Q000821:virology; D016655:HIV Core Protein p24 / Q000378:metabolism*; D015497:HIV-1; D006624:Hippocampus / Q000378:metabolism* / Q000473:pathology / Q000821:virology; D006801:Humans; D007558:Italy / Q000453:epidemiology; D012189:Retrospective Studies
chemical_list: D016564:Amyloid beta-Protein Precursor; D015415:Biomarkers; D016655:HIV Core Protein p24