Human adipose tissue macrophages: m1 and m2 cell surface markers in subcutaneous and omental depots and after weight loss.
BACKGROUND
Macrophages accumulate in adipose tissue and possibly participate in metabolic complications in obesity. Macrophage number varies with adipose tissue site and weight loss, but whether this is accompanied by phenotypic changes is unknown.


OBJECTIVE
The objective of the study was to characterize the activation state of adipose tissue macrophages in human obesity.


METHODS
We performed a single-center prospective study.


METHODS
Paired biopsies of sc and omental adipose tissue were obtained during gastric surgery in 16 premenopausal obese women (aged 41.1 +/- 8.6 yr; body mass index 43.8 +/- 3.4 kg/m(2)). Subcutaneous adipose tissue biopsies were obtained 3 months later in obese subjects and in 10 nonobese women (aged 43.3 +/- 3.5 yr; body mass index 22.5 +/- 0.75 kg/m(2)). The number of macrophages stained with CD40, CD206, and CD163 surface markers was determined by immunochemistry.


RESULTS
The number of CD40(+) macrophages significantly increased with obesity and in omental vs. sc adipose tissue in obese women. No significant changes in CD163(+) and CD206(+) macrophage counts was found with obesity and fat pad anatomical location. Three months after gastric surgery, the ratio of CD40(+) to CD206(+) macrophages was 2-fold lower than before surgery in the sc adipose tissue of obese subjects (P < 0.001) due to a concomitant decrease of CD40(+) and increase of CD206(+) macrophages counts.


CONCLUSIONS
We suggest that the activation state of adipose tissue macrophages is weighted toward M1 over M2 status in obese subjects and switch to a less proinflammatory profile 3 months after gastric bypass.
Aron-Wisnewsky
Judith
J
Institut National de la Santé et de la Recherche Médicale, Unité 872 Eq7, 75007 Paris, France.
Tordjman
Joan
J
Poitou
Christine
C
Darakhshan
Froogh
F
Hugol
Danielle
D
Basdevant
Arnaud
A
Aissat
Abdelhalim
A
Guerre-Millo
Michèle
M
Clément
Karine
K
D000273:Adipose Tissue / Q000166:cytology* / Q000473:pathology; D000328:Adult; D015703:Antigens, CD / Q000032:analysis; D015214:Antigens, Differentiation, Myelomonocytic / Q000032:analysis; D015415:Biomarkers / Q000032:analysis; D001706:Biopsy; D019013:CD40 Antigens / Q000032:analysis; D002462:Cell Membrane / Q000737:chemistry; D005260:Female; D015390:Gastric Bypass; D006801:Humans; D007150:Immunohistochemistry; D037181:Lectins, C-Type / Q000032:analysis; D008264:Macrophages / Q000166:cytology* / Q000502:physiology; D000090323:Mannose Receptor; D037241:Mannose-Binding Lectins / Q000032:analysis; D008875:Middle Aged; D009765:Obesity / Q000473:pathology / Q000601:surgery; D009852:Omentum / Q000166:cytology / Q000502:physiology*; D011956:Receptors, Cell Surface / Q000032:analysis; D015431:Weight Loss; D000098902:CD163 Antigen
D015703:Antigens, CD; D015214:Antigens, Differentiation, Myelomonocytic; D015415:Biomarkers; D000098902:CD163 Antigen; D019013:CD40 Antigens; D037181:Lectins, C-Type; D000090323:Mannose Receptor; D037241:Mannose-Binding Lectins; D011956:Receptors, Cell Surface