Cell Talk

Abstract

Keloid is a common complication of the wound healing process. Scarce histologic studies describing changes in keloid growth or progression, regarding detailed descriptions of cellular distribution, relationship, or interaction are available. This study aimed to describe the nature, types, and interactions of immune cells (lymphocytes, macrophages, and mast cells), which predominate in keloid complications and may play a role in fibroblastic activation. In this study, 44 samples of keloid were collected, processed, and examined using both light (including routine and immunocytochemical staining) and scanning electron microscopy (SEM). This histologic study showed the characteristic disposition of abnormally thick collagen bundles and newly formed blood vessels in the keloid tissue. The latter showed endothelial hypertrophy, thickened walls with the disposition of homogenous substances, and fibrillar collagen in the perivascular tissue. Numerous mast cells were also observed. Marked cellular infiltration in the perivascular regions and among abnormal collagen was observed. Immunohistochemistry showed the dominance of (CD3) T lymphocytes together with the macrophages (CD68). Among the interesting findings that this study focused on was the cellular interaction. The contact was noticed between the fibroblast and mast cell, the fibroblast and T lymphocyte, the macrophage and both fibroblast and lymphocyte. This cell-cell interaction or contact may explain what was called in literature "cell talk" via cytokines secreted by these cells or through direct gap junctions. In conclusion, cell talk is a phenomenon that was noticed in many pathologic lesions and could explain the mechanism by which different cytokines are secreted by different cells to initiate disease or promote healing.

Sulforaphane suppresses cell growth and collagen expression of keloid fibroblasts

“…Various coculture systems have been used for the examination of keloid fibroblasts due to the absence of suitable animal models for keloid formation. In this study, we also used PBMC, which infiltrate keloid fibroblasts in keloid tissues, for coculture with KF112 cells . The role of monocytes/macrophages has not yet been fully explored in keloid pathogenesis, but they are thought to be involved in the development of fibrosis by secreting various cytokines and growth factors .…”

Treg‐enriched CD4+ T cells attenuate collagen synthesis in keloid fibroblasts

“…Inflammatory cells have been shown to play an important role in fibrosis associated with wound healing and scleroderma. Compared with the normal dermis, a larger number of T cells and an increased CD4/CD8 ratio have been detected in the keloid dermis .…”

Development of Mast Cells and Importance of Their Tryptase and Chymase Serine Proteases in Inflammation and Wound Healing

“…MCs have been implicated in this process, as histology revealed increased numbers of MCs in keloids (Shaker, Ayuob, & Hajrah, 2011). When keloids were treated with intralesional cryotherapy, improvement of the lesions was correlated with decreased numbers of MCs, as assessed histochemically (Har-Shai et al, 2011).…”