Possible involvement of SDF-1/CXCL12 in the pathogenesis of Degos disease.

BACKGROUND: Degos disease or malignant atrophic papulosis is a rare occlusive vasculopathic disease characterized by pathognomonic cutaneous lesions and frequently fatal systemic involvement. The etiology of malignant atrophic papulosis remains unclear, and there is currently no effective treatment for malignant atrophic papulosis. Several chemokines can potentiate and expand the platelet response to increase thrombus formation. Among these chemokines, this study examined the expression of stromal cell-derived factor (SDF)-1/CXCL12, which is secreted by bone-marrow stromal and endothelial cells, activates megakaryocyte precursors, and costimulates platelet activation. OBJECTIVE: We sought to investigate and compare the expression of SDF-1/CXCL12 in tissue sections taken from 2 patients with Degos disease, 2 patients with other vaso-occlusive diseases, and 2 healthy control subjects. METHODS: Immunohistochemical staining involving antibodies to SDF-1/CXCL12 was performed on 3 skin biopsy specimens taken from 2 patients with Degos disease, 1 from a patient with antiphospholipid syndrome, 1 from a patient with cryoglobulinemia, and 2 from healthy control subjects. RESULTS: Strong SDF-1/CXCL12 staining was observed in the infiltrating inflammatory cells in the perivascular, intravascular, and perineural areas in tissue samples from patients with Degos disease. No staining was observed in samples from patients with antiphospholipid syndrome or cryoglobulinemia or from healthy control subjects. LIMITATIONS: The number of cases available for evaluation was small. The findings were based primarily on the immunohistochemical results and were not confirmed using other techniques. CONCLUSIONS: The intense staining of SDF-1/CXCL12 in lesions attributed to Degos disease, demonstrated for the first time to our knowledge in this study, suggests SDF-1/CXCL12 involvement in the pathogenesis of the disease.

Case of pemphigus with immunoglobulin G and A antibodies, binding to both the intercellular spaces and basement membrane zone.

We report a case involving a 62-year-old woman with in vivo-bound immunoglobulin (Ig)G and IgA antibodies in both the intercellular space (ICS) and basement membrane zone (BMZ). Her clinical and histopathological features were identical with those of pemphigus vulgaris, while the immunopathological findings suggested IgG/IgA pemphigus. Direct immunofluorescence (IF) showed in vivo-bound IgG and IgA antibodies in the ICS and BMZ, whereas indirect IF showed circulating IgG but not IgA antibodies in the ICS and BMZ. The anti-ICS IgG bound to desmoglein-3, while the anti-BMZ antibodies bound to the epidermal side of 1 mol/L NaCl-split skin. To the best of our knowledge, only two similar cases have been reported so far. Furthermore, we also examined IgG subclass distribution of the in vivo-bound and circulating anti-ICS and BMZ antibodies, and found that IgG1, IgG2 and IgG4 bound to ICS of the lesional skins, while IgG1 and IgG3 bound to the BMZ. The circulating anti-ICS antibodies belonged to IgG1 and IgG4, while the circulating anti-BMZ antibodies to IgG1, IgG2 and IgG4. We report a case involving a 62-year-old woman with in vivo-bound immunoglobulin (Ig)G and IgA antibodies in both the intercellular space (ICS) and basement membrane zone (BMZ). Her clinical and histopathological features were identical with those of pemphigus vulgaris, while the immunopathological findings suggested IgG/IgA pemphigus. Direct immunofluorescence (IF) showed in vivo-bound IgG and IgA antibodies in the ICS and BMZ, whereas indirect IF showed circulating IgG but not IgA antibodies in the ICS and BMZ. The anti-ICS IgG bound to desmoglein-3, while the anti-BMZ antibodies bound to the epidermal side of 1 mol/L NaCl-split skin. To the best of our knowledge, only two similar cases have been reported so far. Furthermore, we also examined IgG subclass distribution of the in vivo-bound and circulating anti-ICS and BMZ antibodies, and found that IgG1, IgG2 and IgG4 bound to ICS of the lesional skins, while IgG1 and IgG3 bound to the BMZ. The circulating anti-ICS antibodies belonged to IgG1 and IgG4, while the circulating anti-BMZ antibodies to IgG1, IgG2 and IgG4.

Effects of decreased vitamin D and accumulated uremic toxin on human CYP3A4 activity in patients with end-stage renal disease.

In patients with end-stage renal disease, not only renal clearance but also hepatic clearance is known to be impaired. For instance, the concentration of erythromycin, a substrate of cytochrome P450 3A4 (CYP3A4), has been reported to be elevated in patients with end-stage renal disease. The purpose of this study is to elucidate the reason for the decrease in hepatic clearance in patients with end-stage renal disease. Deproteinized pooled sera were used to assess the effects of low-molecular-weight uremic toxins on CYP3A4 activity in human liver microsomes and human LS180 cells. Four uremic toxins (3-carboxy-4-methyl-5-propyl-2-furanpropanoic acid, hippuric acid, indole-3-acetic acid, and 3-indoxyl sulfate) present at high concentrations in uremic serum were also studied. Simultaneous treatment of uremic serum (less than 10%) or uremic toxins did not affect testosterone 6ß-hydroxylation in human liver microsomes. On the other hand, pretreatment of each serum activates CYP3A4 in LS180 cells, and the increased CYP3A4 activity in uremic serum-treated cells was smaller than normal serum-treated cells. In addition, CYP3A4 and CYP24A1 mRNA levels also increased in LS180 cells exposed to normal serum, and this effect was reduced in uremic serum-treated cells and in cells exposed to uremic serum added to normal serum. Furthermore, addition of 1,25-dihydroxyvitamin D to uremic serum partially restored the serum effect on CYP3A4 expression. The present study suggests that the decrease of 1,25-dihydroxyvitamin D and the accumulation of uremic toxins contributed to the decreased hepatic clearance of CYP3A4 substrates in patients with end-stage renal disease.