title: Immune function in Amazonian horticulturalists.
abstract: BACKGROUND
  Amazonian populations are exposed to diverse parasites and pathogens, including protozoal, bacterial, fungal and helminthic infections. Yet much knowledge of the immune system is based on industrialised populations where these infections are relatively rare.
  
  
  OBJECTIVE
  This study examines distributions and age-related differences in 22 measures of immune function for Bolivian forager-horticulturalists and US and European populations.
  
  
  METHODS
  Subjects were 6338 Tsimane aged 0-90 years. Blood samples collected between 2004-2014 were analysed for 5-part blood differentials, C-reactive protein, erythrocyte sedimentation rate (ESR) and total immunoglobulins E, G, A and M. Flow cytometry was used to quantify naïve and non-naïve CD4 and CD8 T cells, natural killer cells, and B cells.
  
  
  RESULTS
  Compared to reference populations, Tsimane have elevated levels of most immunological parameters, particularly immunoglobulins, eosinophils, ESR, B cells, and natural killer cells. However, monocytes and basophils are reduced and naïve CD4 cells depleted in older age groups.
  
  
  CONCLUSIONS
  Tsimane ecology leads to lymphocyte repertoires and immunoglobulin profiles that differ from those observed in industrialised populations. These differences have consequences for disease susceptibility and co-vary with patterns of other life history traits, such as growth and reproduction.
authors.affiliation: a Department of Anthropology , University of California , Santa Barbara , CA , USA ;|b Tsimane Health and Life History Project , San Borja , Bolivia ;
authors.forename: Aaron D
authors.initials: AD
authors.lastname: Blackwell
authors.affiliation: a Department of Anthropology , University of California , Santa Barbara , CA , USA ;|b Tsimane Health and Life History Project , San Borja , Bolivia ;|c Center for Evolutionary Medicine, Arizona State University , Tempe , AZ , USA ;|d School of Human Evolution and Social Change, Arizona State University , Tempe , AZ , USA ;
authors.forename: Benjamin C
authors.initials: BC
authors.lastname: Trumble
authors.affiliation: b Tsimane Health and Life History Project , San Borja , Bolivia ;
authors.forename: Ivan
authors.initials: I
authors.lastname: Maldonado Suarez
authors.affiliation: b Tsimane Health and Life History Project , San Borja , Bolivia ;|e Department of Anthropology , University of New Mexico , Albuquerque , NM , USA ;|f Institute for Advanced Study in Toulouse , Toulouse , France ;
authors.forename: Jonathan
authors.initials: J
authors.lastname: Stieglitz
authors.affiliation: b Tsimane Health and Life History Project , San Borja , Bolivia ;|e Department of Anthropology , University of New Mexico , Albuquerque , NM , USA ;
authors.forename: Bret
authors.initials: B
authors.lastname: Beheim
authors.affiliation: g Department of Anthropology , University of Oregon , Eugene , OR , USA.
authors.forename: J Josh
authors.initials: JJ
authors.lastname: Snodgrass
authors.affiliation: b Tsimane Health and Life History Project , San Borja , Bolivia ;|e Department of Anthropology , University of New Mexico , Albuquerque , NM , USA ;
authors.forename: Hillard
authors.initials: H
authors.lastname: Kaplan
authors.affiliation: a Department of Anthropology , University of California , Santa Barbara , CA , USA ;|b Tsimane Health and Life History Project , San Borja , Bolivia ;
authors.forename: Michael
authors.initials: M
authors.lastname: Gurven
mesh_terms: D000293:Adolescent; D000328:Adult; D017677:Age Distribution; D000368:Aged; D000369:Aged, 80 and over; D000383:Agriculture; D001402:B-Lymphocytes / Q000166:cytology; D015415:Biomarkers / Q000097:blood; D001799:Blood Sedimentation; D001938:Brazil; D002097:C-Reactive Protein / Q000378:metabolism; D002648:Child; D002675:Child, Preschool; D006801:Humans; D007109:Immunity; D056724:Immunity, Humoral / Q000276:immunology; D007113:Immunity, Innate / Q000276:immunology; D007223:Infant; D007231:Infant, Newborn; D018836:Inflammation Mediators / Q000378:metabolism; D007694:Killer Cells, Natural / Q000166:cytology; D018655:Lymphocyte Count; D016131:Lymphocyte Subsets / Q000276:immunology; D008875:Middle Aged; D018418:Th2 Cells / Q000276:immunology; D055815:Young Adult
chemical_list: D015415:Biomarkers; D018836:Inflammation Mediators; D002097:C-Reactive Protein
keywords: Immune function; South America; Tsimane; horticulturalists; life history