Cord blood-derived human cultured mast cells produce transforming growth factor β1

• Published in: Clinical and experimental allergy Vol. 29; no. 1; pp. 105 - 113
• Main Authors: KANBE, N, KUROSAWA, M, NAGATA, H, SAITOH, H, MIYACHI, Y
• Format: Journal Article
• Language: English
• Published: Oxford BSL Blackwell Science Ltd 01.01.1999; Blackwell
• Subjects: Analysis of the immune response. Humoral and cellular immunity; Biological and medical sciences; cord blood; Fundamental and applied biological sciences. Psychology; Fundamental immunology; growth-inhibition assay; Immunobiology; immunocytochemical staining; interleukin-6; Lymphokines, interleukins ( function, expression); mast cell; Regulatory factors and their cellular receptors; reverse transcriptase-polymerase chain reaction; stem cell factor; transforming growth factor β1; Human; Cell culture; Mast cell; Transforming growth factor β1; Fibrosis; Growth factor
• ISSN: 0954-7894; 1365-2222
• DOI: 10.1046/j.1365-2222.1999.00459.x

Background Mast cells frequently accumulate at the site of fibrosis and their contribution has been suspected in the pathogenesis of fibrotic conditions. However, it still remains unknown whether human mast cells synthesize transforming growth factor β1 (TGF‐β1). Objective We have investigated whether cord blood‐derived human cultured mast cells express messenger RNA (mRNA) for TGF‐β and produce bioactive TGF‐β1. Methods Mast cells were obtained by culturing mononuclear cells from cord blood in the presence of stem cell factor and interleukin‐6. Expression of mRNA for TGF‐β1 was examined by the method of reverse transcriptase‐polymerase chain reaction (RT‐PCR). Immunocytochemical staining for TGF‐β and growth‐inhibitory assay using Mv1Lu cells were also performed. Results The cultured human mast cells constitutively expressed mRNA for TGF‐β1. With calcium ionophore A23187, the intensity of the PCR‐amplified band for TGF‐β1 was not increased. Immunocytochemical staining showed that the cultured mast cells were positive for both latency‐associated peptide and activated forms of TGF‐β. Bioassay with Mv1Lu cells and R 4‐2 mutant cells showed that mast‐cell conditioned medium had a bioactivity of TGF‐β1. Conclusion Cord blood‐derived human cultured mast cells constitutively express mRNA for TGF‐β1 and produce functional TGF‐β1. Because TGF‐β1 has been shown to be highly fibrogenic, these results may highlight a novel role for human mast cells in tissue fibrosis.