Renal macrophages monitor and remove particles from urine to prevent tubule obstruction.

When the filtrate of the glomerulus flows through the renal tubular system, various microscopic sediment particles, including mineral crystals, are generated. Dislodging these particles is critical to ensuring the free flow of filtrate, whereas failure to remove them will result in kidney stone formation and obstruction. However, the underlying mechanism for the clearance is unclear. Here, using high-resolution microscopy, we found that the juxtatubular macrophages in the renal medulla constitutively formed transepithelial protrusions and "sampled" urine contents. They efficiently sequestered and phagocytosed intraluminal sediment particles and occasionally transmigrated to the tubule lumen to escort the excretion of urine particles. Mice with decreased renal macrophage numbers were prone to developing various intratubular sediments, including kidney stones. Mechanistically, the transepithelial behaviors of medulla macrophages required integrin ß1-mediated ligation to the tubular epithelium. These findings indicate that medulla macrophages sample urine content and remove intratubular particles to keep the tubular system unobstructed.

Epigenetic Regulation of IL-23 by E3 Ligase FBXW7 in Dendritic Cells Is Critical for Psoriasis-like Inflammation.

Dendritic cells (DCs), a driver of psoriasis pathogenesis, produce IL-23 and trigger IL-23/IL-17 cytokine axis activation. However, the mechanisms regulating IL-23 induction remain unclear. In the current study, we found that mice with E3 ligase FBXW7 deficiency in DCs show reduced skin inflammation correlated with the reduction of IL-23/IL-17 axis cytokines in the imiquimod-induced psoriasis model. Fbxw7 deficiency results in decreased production of IL-23 in DCs. FBXW7 interacts with the lysine N-methyltransferase suppressor of variegation 39 homolog 2 (SUV39H2), which catalyzes the trimethylation of histone H3 Lys9 (H3K9) during transcription regulation. FBXW7 mediates the ubiquitination and degradation of SUV39H2, thus decreasing H3K9m3 deposition on the Il23a promoter. The Suv39h2 knockout mice displayed exacerbated skin inflammation with the IL-23/IL-17 axis overactivating in the psoriasis model. Taken together, our results indicate that FBXW7 increases IL-23 expression in DCs by degrading SUV39H2, thereby aggravating psoriasis-like inflammation. Inhibition of FBXW7 or the FBXW7/SUV39H2/IL-23 axis may represent a novel therapeutic approach to psoriasis.

FXYD3 enhances IL-17A signaling to promote psoriasis by competitively binding TRAF3 in keratinocytes.

Psoriasis is a common chronic inflammatory skin disease characterized by inflammatory cell infiltration and epidermal hyperplasia. However, the regulatory complexity of cytokine and cellular networks still needs to be investigated. Here, we show that the expression of FXYD3, a member of the FXYD domain-containing regulators of Na+/K+ ATPases family, is significantly increased in the lesional skin of psoriasis patients and mice with imiquimod (IMQ)-induced psoriasis. IL-17A, a cytokine important for the development of psoriatic lesions, contributes to FXYD3 expression in human primary keratinocytes. FXYD3 deletion in keratinocytes attenuated the psoriasis-like phenotype and inflammation in an IMQ-induced psoriasis model. Importantly, FXYD3 promotes the formation of the IL-17R-ACT1 complex by competing with IL-17R for binding to TRAF3 and then enhances IL-17A signaling in keratinocytes. This promotes the activation of the NF-κB and MAPK signaling pathways and leads to the expression of proinflammatory factors. Our results clarify the mechanism by which FXYD3 serves as a mediator of IL-17A signaling in keratinocytes to form a positive regulatory loop to promote psoriasis exacerbation. Targeting FXYD3 may serve as a potential therapeutic approach in the treatment of psoriasis.

[Pathology of AIDS-related lymphadenopathy: a study of 18 biopsy cases].

OBJECTIVE: To study the clinicopathologic features of acquired immunodeficiency syndrome (AIDS)-related lymphadenopathy and to elucidate the salient features helpful in achieving a correct pathologic differentiated diagnosis. METHODS: Eighteen cases of AIDS-related lymphadenopathy were retrieved from the files of the First Affiliated Hospital of Guangxi Medical University from 2001 to 2004. Histochemical stains, including periodic acid-Schiff, acid-fast, Giemsa, Grocott stains and immunohistochemistry (EnVision method), were used to detect the presence of pathogens in tissue sections and classify them. RESULTS: Fifteen of the 18 cases (83%) were stage 4 (i.e. follicular and lymphocytic depletion). Twelve cases were co-infected with Penicillium marneffei and 4 other cases with Mycobacterium, and no pathogen was found in 1. The remaining patient was complicated with diffuse large B-cell lymphoma. CONCLUSIONS: When presented in early stages, AIDS-related lymphadenopathy may be overlooked, especially in routine pathology practice. Awareness of the entity in patients with persistent fever and generalized lymphadenopathy is thus crucial. Florid infection with Penicillium marneffei is also considered as an important predictor for underlying AIDS. Thorough understanding of morphologic features of AIDS-related lymphadenopathy, including possible co-infection, is essential in arriving at the correct diagnosis.

Rare cavernous hemangioma of adrenal gland: case report.

CONTEXT: Cavernous hemangiomas of the adrenal gland are rare benign neoplastic tumors. The clinical presentation of adrenal hemangiomas is usually vague, and they are often discovered incidentally through imaging examination s performed for other reasons. CASE REPORT: We report the case of a non-functional adrenal hemangioma found incidentally in a 37-year-old man with a one-year history of headache and hypertension. A right adrenal mass was detected by means of magnetic resonance imaging. Physical examination and all laboratory values were unremarkable. The patient underwent laparoscopic right adrenal gland resection. Histopathological evaluation confirmed adrenal cavernous hemangioma. CONCLUSIONS: Most occurrences of cavernous hemangiomas of the adrenal gland are non-functional and often discovered incidentally. Although rare, these unusual benign adrenal masses should form part of the differential diagnosis of adrenal neoplasms. The proper treatment for adrenal cavernous hemangioma is surgical removal.

Rare cavernous hemangioma of adrenal gland: case report / Hemangioma cavernoso raro da glândula adrenal: relato de caso

CONTEXT: Cavernous hemangiomas of the adrenal gland are rare benign neoplastic tumors. The clinical presentation of adrenal hemangiomas is usually vague, and they are often discovered incidentally through imaging examination s performed for other reasons. CASE REPORT: We report the case of a non-functional adrenal hemangioma found incidentally in a 37-year-old man with a one-year history of headache and hypertension. A right adrenal mass was detected by means of magnetic resonance imaging. Physical examination and all laboratory values were unremarkable. The patient underwent laparoscopic right adrenal gland resection. Histopathological evaluation confirmed adrenal cavernous hemangioma. CONCLUSIONS: Most occurrences of cavernous hemangiomas of the adrenal gland are non-functional and often discovered incidentally. Although rare, these unusual benign adrenal masses should form part of the differential diagnosis of adrenal neoplasms. The proper treatment for adrenal cavernous hemangioma is surgical removal. .

CONTEXTO: Hemangiomas cavernosos da glândula adrenal são tumores neoplásicos raros, benignos. A apresentação clínica dos hemangiomas adrenais é geralmente vaga e muitas vezes eles são descobertos acidentalmente por exame imagiológico realizado por outras razões. RELATO DE CASO: Nós relatamos um caso de hemangioma adrenal não funcional encontrado por acaso em um homem de 37 anos de idade com histórico de um ano de dor de cabeça e hipertensão. Foi detectada massa adrenal direita por meio de ressonância magnética. Exame físico e todos os valores de laboratoriais estavam normais. O paciente foi submetido a cirurgia laparoscópica para ressecção da glândula adrenal direita. Avaliação histopatológica confirmou hemangioma adrenal cavernoso. CONCLUSÃO: A maioria dos hemangiomas cavernosos de glândula adrenal são não funcionais e muitas vezes descobertos por acaso. Embora raras, essas massas adrenais benignas devem ser parte de um diagnóstico diferencial de neoplasias suprarrenais. O tratamento adequado para o hemangioma adrenal cavernoso é a remoção cirúrgica. .