Gogler Agnieszka, Wilk Agata Małgorzata, Sojka Damian Robert, Adamiec-Organiściok Małgorzata, Matysiak Natalia, Kania Daria, Wiecha Klaudia, Małusecka Ewa, Cortez Alexander Jorge, Zamojski Dawid, Marczyk Michał, Mazurek Agnieszka Maria, Oziębło Sylwia, Scieglinska Dorota
Center for Translational Research and Molecular Biology of Cancer, Maria Sklodowska-Curie National Research Institute of Oncology Gliwice Branch, Wybrzeze Armii Krajowej 15, 44-102, Gliwice, Poland.
Department of Biostatistics and Bioinformatics, Maria Sklodowska-Curie National Research Institute of Oncology Gliwice Branch, Wybrzeze Armii Krajowej 15, 44-102, Gliwice, Poland.
Cell Death Dis. 2025 Apr 26;16(1):344. doi: 10.1038/s41419-025-07565-5.
Chaperone proteins constitute a molecular machinery that controls proteostasis. HSPA2 is a heat shock-non-inducible member of the human HSPA/HSP70 family, which includes several highly homologous chaperone proteins. HSPA2 exhibits a cell type-specific expression pattern in the testis, brain, and multilayered epithelia. It is a crucial male fertility-related factor, but its role in somatic cells is poorly understood. Previously, we found that HSPA2 deficiency can impair epidermal keratinocyte differentiation. In this study, we confirmed the crucial role of HSPA2 in keratinocyte differentiation by investigating immortalized keratinocytes cultured in a reconstructed human epidermis model. Moreover, we uncovered the influence of HSPA2 on immunomodulation. Transcriptomic analysis revealed that the total loss of HSPA2 affected the expression of genes related to keratinocyte differentiation and interleukin- and interferon-mediated signaling. The functional analysis confirmed bidirectional changes associated with the loss of HSPA2. The HSPA2 knockout in HaCaT and Ker-CT keratinocytes, but not HSPA2 overproduction, impaired granular layer development as evidenced by reduced levels of late keratinocyte differentiation markers, filaggrin and involucrin, along with structural abnormalities in the upper epidermal layer. Differentiation defects were accompanied by increased mRNA expression and extracellular secretion of keratinocyte-derived pro-inflammatory IL-6 cytokine and CCL2, CCL8, CXCL1, CXCL6, and CXCL10 chemokines. The loss of HSPA2 also led to increased expression of extracellular HSPA1 and interferon-stimulated genes and secretion of immune cell modulator SLAMF7. Knocking down HSPA1 expression in keratinocytes decreased the secretion of IL-6 and CCL5 release, suggesting extracellular HSPA1's role in the HSPA2-regulated molecular network. To summarize, we uncovered the complex homeostatic role of HSPA2 in epidermal keratinocytes. Our results suggest that dysfunction in HSPA2 activity could be an important pathogenicity factor and potential therapeutic target for inflammatory cutaneous diseases.
伴侣蛋白构成了一个控制蛋白质稳态的分子机制。HSPA2是人类HSPA/HSP70家族中一种热休克非诱导型成员，该家族包括几种高度同源的伴侣蛋白。HSPA2在睾丸、大脑和复层上皮中呈现细胞类型特异性表达模式。它是一个与男性生育力相关的关键因素，但其在体细胞中的作用却知之甚少。此前，我们发现HSPA2缺陷会损害表皮角质形成细胞的分化。在本研究中，我们通过研究在重建的人表皮模型中培养的永生化角质形成细胞，证实了HSPA2在角质形成细胞分化中的关键作用。此外，我们还揭示了HSPA2对免疫调节的影响。转录组分析表明，HSPA2的完全缺失影响了与角质形成细胞分化以及白细胞介素和干扰素介导的信号传导相关基因的表达。功能分析证实了与HSPA2缺失相关的双向变化。HaCaT和Ker-CT角质形成细胞中的HSPA2基因敲除，但不是HSPA2的过量表达，损害了颗粒层的发育，这表现为晚期角质形成细胞分化标志物丝聚蛋白和兜甲蛋白水平降低，以及表皮上层结构异常。分化缺陷伴随着角质形成细胞衍生的促炎白细胞介素-6细胞因子以及CCL2、CCL8、CXCL1、CXCL6和CXCL10趋化因子的mRNA表达增加和细胞外分泌增加。HSPA2的缺失还导致细胞外HSPA1和干扰素刺激基因的表达增加以及免疫细胞调节剂信号淋巴细胞激活分子家族成员7（SLAMF7）的分泌增加。敲低角质形成细胞中HSPA1的表达可减少白细胞介素-6的分泌和CCL5的释放，表明细胞外HSPA1在HSPA2调节的分子网络中的作用。总之，我们揭示了HSPA2在表皮角质形成细胞中的复杂稳态作用。我们的结果表明，HSPA2活性功能障碍可能是炎症性皮肤病的一个重要致病因素和潜在治疗靶点。
