Monocytes Secrete Interleukin‐6 When Co‐Cultured In Vitro with Benign or Malignant Autologous Fragment Spheroids from Squamous Cell Carcinoma Patients

• Published in: Scandinavian journal of immunology 2000-03, Vol.51 (3), p.271-278
• Main Authors: Heimdal, J, Aarstad, H J, Olofsson, J
• Format: Article
• Language: English
• Subjects: Aged; Aged, 80 and over; Carcinoma, Squamous Cell - chemistry; Carcinoma, Squamous Cell - immunology; Carcinoma, Squamous Cell - pathology; Cell Culture Techniques; Cells, Cultured; Coculture Techniques; Female; Fibroblasts - cytology; Head and neck carcinoma; Head and Neck Neoplasms - chemistry; Head and Neck Neoplasms - immunology; Head and Neck Neoplasms - pathology; Humans; Immunohistochemistry; Interleukin-6 - metabolism; Male; Middle Aged; Monocytes - cytology; Monocytes - immunology; Monocytes - metabolism; Spheroids, Cellular - chemistry; Spheroids, Cellular - cytology; Spheroids, Cellular - immunology; Spheroids, Cellular - pathology; Squamous cell carcinoma; Staining and Labeling
• ISSN: 0300-9475; 1365-3083
• DOI: 10.1046/j.1365-3083.2000.00680.x

Biopsies from tumour and benign mucosa were removed from patients with head and neck squamous‐cell carcinoma (HNSCC), chopped into cubes and transferred to a nonadhesive culture system where in vitro fragment (F)‐spheroids were established. The F‐spheroids stabilized within 14 days of culture in vitro with epithelial cells and fibroblasts on the surface. F‐spheroids were co‐cultured with freshly isolated autologous monocytes. The monocytes of 10 of 11 patients secreted interleukin (IL)‐6 at a level similar to that of the average monocyte endotoxin‐stimulated response. Secreted IL‐1β or tumour necrosis factor‐α (TNF‐α) levels greater than 0.1 times the endotoxin‐stimulated secretion were determined in one and two of the 11 co‐culture experiments, respectively. This different monocyte response to F‐spheroids compared with endotoxin stimulation was also present at the mRNA expression level. HNSCC monocytes secreted no IL‐6 after co‐culture with autologous fibroblasts. When monocytes and F‐spheroids were cultured separated by a semipermeable membrane, the IL‐6 supernatant level was only ≈ 25% of that observed during co‐culture with direct contact. F‐spheroids secreted only trace amounts of IL‐6. In conclusion, monocytes of HNSCC patients generally secrete IL‐6, but not IL‐1β or TNF‐α, after stimulation with epithelial‐associated components of F‐spheroids upon direct contact and in part by a soluble substance.