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Lu, C. P.-J.

Publications and source records attributed to Lu, C. P.-J..

3 recordsLinked to original sources

Prepatterned Tissue Stiffness Gradient Controls Organ shape and size

Organ morphogenesis is orchestrated by precise coupling of mechanical and biochemical signals, yet how these two signals are integrated within tissue niche to regulate organ shape and size remains poorly understood. Here, using sweat gland as a tractable model of exocrine mini-organs, we demonstrate that dermal fibroblasts play a key role to translate prepatterned tissue stiffness gradients into spatial Wnt5a gradients via Piezo1-mediated mechanosensing. Following epidermal placode formation, progenitor cells collectively invaginate into the dermis, where spatiotemporally graded Wnt5a directs their sequential transition from ductal to glandular fate in softer distal dermis, specifying distinct exocrine compartments. Perturbation of dermal stiffness gradients and mechanosensing in vivo and ex vivo alters Wnt5a expression levels and gradient patterns and thereby changes the ductal length and glandular size, revealing a direct link between tissue mechanics and organ dimensions. To recapitulate this process in vitro, we engineer a microfluidic platform capable of generating robust and linear morphogen gradients in 3D, allowing duct-to-gland fate transitions to occur at a high resolution. Together, our finding identifies prepatterned stiffness gradients as a master upstream regulator of coupled mechanical-biochemical signaling, define a mechanistic framework for two-step sequential glandular morphogenesis, and offer new strategies for engineering glandular epithelia in regenerative medicine.

developmental biology↗

Epidermal SIRT1 and BDNF modulate mechanical allodynia in mouse models of diabetic neuropathy

Diabetic neuropathy is a debilitating disorder characterized by spontaneous and mechanical pain. The role of skin mechanoreceptors in the development of mechanical pain (allodynia) is unclear. We discovered that mice with diabetic neuropathy had decreased sirtuin 1 (SIRT1) deacetylase activity in foot skin, leading to reduced expression of brain-derived neurotrophic factor (BDNF) and subsequent loss of innervation in Meissner corpuscles, a mechanoreceptor expressing the BDNF receptor TrkB. When SIRT1 was depleted from skin, the mechanical allodynia worsened in diabetic neuropathy mice, likely due to retrograde degeneration of the Meissner-corpuscle innervating A{beta} axons and aberrant formation of Meissner corpuscles which may have increased the mechanosensitivity. The same phenomenon was also noted in skin BDNF knockout mice. Furthermore, overexpression of SIRT1 in skin induced Meissner corpuscle reinnervation and regeneration, resulting in significant improvement of diabetic mechanical allodynia. Overall, the findings suggested that skin-derived SIRT1 and BDNF function in the same pathway in skin sensory apparatus regeneration and highlighted the potential of developing topical SIRT1-activating compounds as a novel treatment for diabetic mechanical allodynia.

neuroscience↗

Defining Epidermal Stem Cell Fate Infidelity and Immunogenicity in Hidradenitis Suppurativa at the Single-Cell Resolution

Hidradenitis suppurativa (HS) is a severe chronic inflammatory skin disease affecting human apocrine sweat gland-bearing skin regions. One unique feature of HS is the development of keratinized sinus tracts that grow extensively deep in the dermis and are highly immunogenic. Here, we demonstrated that the stem cell fate infidelity exists in the HS sinus tracts, which exhibit features of both surface epidermis and appendages. Using single cell transcriptome analyses, we finely dissected different compartments of the HS epithelium and identified their respective changes in cytokine expression during disease progression and the critical interactions with the immune cells. Together, our work provides advanced understanding of the pathological epidermal remodeling and important implications for HS therapeutics.

cell biology↗