Src Homology 2 Domain-Containing Protein Tyrosine Phosphatase Substrate 1 Regulates the Migration of Langerhans Cells from the Epidermis to Draining Lymph Nodes

Abstract

Src homology 2 domain-containing protein tyrosine phosphatase substrate 1 (SHPS-1) is a member of the signal regulatory protein family in which the extracellular region interacts with its ligand, CD47. Recent studies have demonstrated that SHPS-1 plays an important role in cell migration and cell adhesion. We demonstrate in this study, using immunohistochemical and flow cytometric analyses, that murine Langerhans cells (LCs) express SHPS-1. Treatment of mice ears with 2,4-dinitro-1-fluorobenzene significantly reduced the number of epidermal LCs, and that reduction could be reversed by pretreatment with mAb to SHPS-1 or the CD47-Fc fusion protein. Treatment with the SHPS-1 mAb in vivo reduced the number of FITC-bearing cells in the lesional lymph nodes after the application of FITC to the skin. The SHPS-1 mAb inhibited the in vivo TNF-α-induced migration of LCs. The emigration of dendritic cells expressing I-Ab+ from skin explants to the medium was also reduced by the SHPS-1 mAb. We further demonstrate that the chemotaxis of a murine dendritic cell line, XS52, by macrophage inflammatory protein-3β was significantly inhibited by treatment with the SHPS-1 mAb or CD47-Fc recombinant protein. Finally, we show that migration of LCs was attenuated in mutant mice that lack the intracellular domain of SHPS-1. These observations show that the ligation of SHPS-1 with the SHPS-1 mAb or with CD47-Fc abrogates the migration of LCs in vivo and in vitro, which suggests that the SHPS-1-CD47 interaction may negatively regulate LC migration.

Src homology 2 domain‐containing protein tyrosine phosphatase substrate 1 regulates the induction of Langerhans cell maturation

“…This is further supported by the observation that the TNF-a-induced up-regulation of I-A expression by LC is attenuated by the ligation of SHPS-1, because it has been reported that TNF-a induces both the maturation of DC and the phosphorylation of tyrosine residues of SHPS-1 and the consequent recruitment of 17]. We previously reported that the motility of LC is attenuated in wild-type mice by the engagement of SHPS-1 and in SHPS-1 mutant mice [32]. As immature DC, following induction of maturation after stimulation by inflammatory cytokines or haptens, up-regulate CCR7 [39,41,42], our next question was whether or not the expression of CCR7 on LC is impaired during the maturational changes following hapten application to SHPS-1 mutant mice.…”

“…Murine epidermal sheets were prepared as previously described [32]. After fixation, the sheets were simultaneously incubated at room temperature for 30 min with FITCconjugated mouse anti-mouse I-A b mAb and PE-conjugated rat anti-mouse CD86 mAb, each diluted 1:100 in 5% BSA/PBS.…”

“…The epidermal sheets were prepared as previously described [32]. They were cultured in 24-well tissue culture plates in 1.5 mL culture medium (10% FCS, RPMI1640 with 20 lg/mL CD47-Fc protein or control human IgG-Fc) for 24 or 48 h at 37 C. At least six explants were cultured for each experimental condition.…”

“…We recently demonstrated that LC/DC migration is significantly inhibited by the ligation of SHPS-1 and that LC migration is impaired in SHPS-1 mutant mice that lack the intracellular domain of SHPS-1 [32]. In this study, we focused on LC maturation and investigated whether that process is affected by the ligation of SHPS-1.…”

“…Thus, the epidermal skin explant culture system is useful for investigating the phenotypic maturation of LC by exogenous stimulants. We previously showed that SHPS-1 is selectively expressed on LC in the epidermis [32], which indicated that ligation of SHPS-1 with its ligands exclusively affects LC but not keratinocytes. These results indicate that engagement of SHPS-1 negatively regulates the phenotypic maturation of LC in vivo and ex vivo.…”