title: HIV-1 exposed uninfected men who have sex with men have increased levels of salivary CC-chemokines associated with sexual behavior.
abstract: OBJECTIVE
  To determine whether soluble molecules with known anti-HIV-1 activity are increased in saliva of HIV-1 exposed uninfected individuals of discordant couples of men who have sex with men (MSM), and whether the levels of these molecules are associated with genetic polymorphisms, sexual behavior and/or HIV-1 neutralizing capacity.
  
  
  METHODS
  Saliva and PBMC were collected from exposed uninfected individuals (n=25), and low-risk controls (n=22). Levels of CCL2, CCL3, CCL4, CCL5 and CCL11 were detected by Luminex, and SLPI, LL-37, alpha-defensins and IgA2 were detected by ELISA. Single nucleotide polymorphisms (SNPs) were investigated using mass spectrometry or PCR-sequencing. HIV-1 neutralizing activity was assessed using PBMCbased neutralization assays. Self-reported questionnaires described sexual behavior.
  
  
  RESULTS
  Exposed uninfected individuals had significantly higher levels of salivary CCL2, CCL4, CCL5 and CCL11 as compared with controls although genetic polymorphisms within the corresponding regions were equally distributed. IgA2 was also increased in exposed uninfected individuals, whereas neither CCL3, SLPI, LL-37 nor alpha-defensins differed between exposed uninfected individuals and controls. The HIV-1 neutralizing capacity of saliva was associated with higher levels of CC-chemokines (but not SLPI, LL-37, alpha-defensins or IgA2) in both exposed uninfected individuals and controls. The increased levels of CC-chemokines were associated with a higher frequency of unprotected oral sex and/or additional casual sex partners.
  
  
  CONCLUSIONS
  HIV-1 exposed uninfected MSM had higher levels of salivary CC-chemokines compared with controls, this finding associated with sexual behavior rather than with genetic polymorphisms. The increased levels of CC-chemokines associated with HIV-1 neutralizing capacity in saliva.
authors.affiliation: Department of Medicine, Solna, Infectious Disease Unit, Center for Molecular Medicine, Karolinska Institutet, Karolinska University Hospital, Stockholm, Sweden. klara.hasselrot@ki.se
authors.forename: Klara
authors.initials: K
authors.lastname: Hasselrot
authors.forename: Göran
authors.initials: G
authors.lastname: Bratt
authors.forename: Kristina
authors.initials: K
authors.lastname: Duvefelt
authors.forename: Taha
authors.initials: T
authors.lastname: Hirbod
authors.forename: Eric
authors.initials: E
authors.lastname: Sandström
authors.forename: Kristina
authors.initials: K
authors.lastname: Broliden
mesh_terms: D000328:Adult; D019742:Chemokines, CC / Q000032:analysis*; D004797:Enzyme-Linked Immunosorbent Assay; D015483:HIV Antibodies / Q000502:physiology; D015658:HIV Infections / Q000276:immunology*; D015497:HIV-1 / Q000276:immunology*; D018451:Homosexuality, Male; D006801:Humans; D007113:Immunity, Innate / Q000502:physiology; D008297:Male; D009061:Mouth Mucosa / Q000276:immunology; D009500:Neutralization Tests; D012463:Saliva / Q000276:immunology*; D012725:Sexual Behavior; D011795:Surveys and Questionnaires
chemical_list: D019742:Chemokines, CC; D015483:HIV Antibodies