PURPOSE: It is well appreciated that mast cells (MCs) demonstrate tissue-specific imprinting, with different biochemical and functional properties between connective tissue MCs (CTMCs) and mucosal MCs (MMCs). Although in vitro systems have been developed to model these different subsets, there has been limited investigation into the functional characteristics of the 2 major MC subsets. Here, we report the immunologic characterization of 2 MCs subsets developed in vitro from bone marrow progenitors modeling MMCs and CTMCs. METHODS: We grew bone marrow for 4 weeks in the presence of transforming growth factor (TGF)-β, interleukin (IL)-9, IL-3, and stem cell factor (SCF) to generate MMCs, and IL-4, IL-3, and SCF to generate CTMCs. RESULTS: CTMCs and MMCs differed in growth rate and protease content, but their immune characteristics were remarkably similar. Both subsets responded to immunoglobulin E (IgE)-mediated activation with signaling, degranulation, and inflammatory cytokine release, although differences between subsets were noted in IL-10. CTMCs and MMCs showed a similar toll-like receptor (TLR) expression profile, dominated by expression of TLR4, TLR6, or both subsets were responsive to lipopolysaccharide (LPS), but not poly(I:C). CTMCs and MMCs express receptors for IL-33 and thymic stromal lymphopoietin (TSLP), and respond to these cytokines alone or with modified activation in response to IgE cross-linking. CONCLUSIONS: The results of this paper show the immunologic characterization of bone marrow-derived MMCs and CTMCs, providing useful protocols for in vitro modeling of MC subsets.
Bone Marrow ; Connective Tissue* ; Cytokines ; Immunoglobulin E ; Immunoglobulins ; In Vitro Techniques ; Interleukin-10 ; Interleukin-3 ; Interleukin-33 ; Interleukin-4 ; Interleukins ; Mast Cells* ; Stem Cell Factor ; Toll-Like Receptors ; Transforming Growth Factors

Introduction:We assessed the role of the Pirani score in determining the number of casts and its ability to suggest requirement for tenotomy in the management of clubfoot by the Ponseti method. Materials and Methods:Prospective analysis of 66 (110 feet) cases of idiopathic clubfoot up to one year of age was done. Exclusion criteria included children more than one year of age at the start of treatment, non-idiopathic cases and previously treated or operated cases. Results: The initial Pirani score was (5.5±0.7) for the tenotomy group and the initial Pirani score was (3.3±1.6) for the non-tenotomy group. There was a significant difference between the initial Pirani score for the tenotomy and the nontenotomy group with t= -7.9, df= 64 p<0.0001. The tenotomy group had a significantly higher number of casts (four to seven) compared to non-tenotomy group (two to five) t=-10.4, df=64, p<0.0001. Spearman’s rank correlation coefficient was significant and confirmed positive correlation between the initial Pirani score and the number of casts required to correct the deformity (r = 0.931, p<0.0001). Conclusion: Initial high Pirani score suggests the need for greater number of casts to achieve correction and probable need for tenotomy. The number of casts required in achieving complete correction increases with increase in the initial Pirani score. The initial high hindfoot score (2.5-3) signifies the probable need of a minor surgical intervention of percutaneous tendoachilles tenotomy. Based on the initial Pirani score, parents can be informed about the probable duration of treatment and the need for tenotomy.