title: Mechanisms for monocyte activation in co-culture with autologous tumor spheroids.
abstract: Biopsies from carcinoma tissue and benign control mucosa from head and neck squamous cell carcinoma patients were used to establish fragment (F)-spheroids in vitro. We have previously shown that autologous monocytes co-cultured with F-spheroids in vitro secrete interleukin (IL)-6 upon 24h in co-culture. Presently, the aim was to study the mechanisms of this monocyte secretion. Paraformaldehyde (0.1% for 2min) or actinomycin-D (1 microg/ml for 24h) pre-treatment of the F-spheroids abolished the monocyte IL-6 co-culture response. Addition of glucose (100mM) or mannose (100mM), and to some extent galactose (100mM), but not fructose (100mM) to the co-cultures, partly inhibited the monocyte IL-6 co-culture response, but such addition did not inhibit the in vitro monocyte lipopolysaccharide (LPS)-generated IL-6 secretion. When mannose was added to the co-cultures, monocyte IL-6 mRNA expression was eradicated in malignant co-cultures and reduced to a low level in benign co-cultures. Addition of mouse anti-human beta(1)-integrin (anti-CD29) antibody (2 microg/ml) diminished the IL-6 co-culture response but not the monocyte LPS-generated IL-6 response. In conclusion, the monocyte IL-6 co-culture response is dependent on live spheroids and to some extent on direct contact with the F-spheroids, possibly via lectin-like receptor(s), the mannose receptor and beta(1)-integrin.
authors.affiliation: Department of Otolaryngology/Head and Neck Surgery, Haukeland University Hospital, N-5021, Bergen, Norway.
authors.forename: C
authors.initials: C
authors.lastname: Olsnes
authors.forename: J-H
authors.initials: JH
authors.lastname: Heimdal
authors.forename: K
authors.initials: K
authors.lastname: Kross
authors.forename: J
authors.initials: J
authors.lastname: Olofsson
authors.forename: H J
authors.initials: HJ
authors.lastname: Aarstad
mesh_terms: D000818:Animals; D000906:Antibodies / Q000494:pharmacology; D002294:Carcinoma, Squamous Cell; D018920:Coculture Techniques; D003470:Culture Media / Q000737:chemistry; D003609:Dactinomycin / Q000494:pharmacology; D005557:Formaldehyde / Q000494:pharmacology; D005690:Galactose / Q000494:pharmacology; D005947:Glucose / Q000494:pharmacology; D006258:Head and Neck Neoplasms; D006801:Humans; D019012:Integrin beta1 / Q000276:immunology; D015850:Interleukin-6 / Q000032:analysis / Q000096:biosynthesis*; D008070:Lipopolysaccharides / Q000494:pharmacology; D008358:Mannose / Q000494:pharmacology; D051379:Mice; D009000:Monocytes / Q000187:drug effects / Q000276:immunology*; D016133:Polymerase Chain Reaction; D011108:Polymers / Q000494:pharmacology; D012333:RNA, Messenger / Q000032:analysis; D018874:Spheroids, Cellular / Q000187:drug effects / Q000378:metabolism; D013997:Time Factors
chemical_list: D000906:Antibodies; D003470:Culture Media; D019012:Integrin beta1; D015850:Interleukin-6; D008070:Lipopolysaccharides; D011108:Polymers; D012333:RNA, Messenger; D003609:Dactinomycin; D005557:Formaldehyde; D005947:Glucose; D008358:Mannose; D005690:Galactose; C003043:paraform