Retrospective study of the clinical significance of the neutrophil-to-lymphocyte ratio in 79 patients with palmoplantar pustulosis.

Palmoplantar pustulosis (PPP) is a chronic relapsing inflammatory skin disease characterized by multiple vesicles, pustules, and erythematous plaques on the palms and soles. The exacerbation of PPP is strongly associated with focal infections, such as tonsillitis, dental infections, and sinusitis, in Japan. Recently, the neutrophil-to-lymphocyte ratio (NLR) has been widely used as a convenient and useful marker for clinical conditions and various diseases; however, an association between PPP and NLR has not yet been established. We retrospectively analyzed 79 patients with PPP from our hospital to evaluate the clinical significance of the NLR. The average NLR value in patients with PPP was significantly higher than that in healthy controls (2.30 ± 1.02 vs 1.69 ± 0.45, P < 0.001). A comparative analysis of patients with PPP with and without infectious complications showed that there was a statistical difference in the NLR between patients with PPP with and without focal infections, whereas no significant difference was found for metal allergy, smoking, and pustulotic arthro-osteitis. Multivariate analysis indicated that the NLR was significantly associated with focal infections (odds ratio = 18.38, 95% confidence interval 3.86-87.35, P < 0.001). The NLR was also significantly correlated with C-reactive protein levels (P = 0.013, r = 0.2857). Interestingly, after symptom improvement, the NLR significantly decreased from the baseline levels. Furthermore, statistical analysis using the Youden's index revealed that an NLR of 2.28 or higher was associated with the risk of any focal infections in patients with PPP. These results suggest that the NLR has potential applications as a biomarker of the presence of focal infections in patients with PPP.

Periostin-An inducer of pro-fibrotic phenotype in monocytes and monocyte-derived macrophages in systemic sclerosis.

Enhanced circulating blood periostin levels positively correlate with disease severity in　patients with systemic sclerosis (SSc). Monocytes/macrophages are predominantly associated with the pathogenesis of SSc, but the effect of periostin on immune cells, particularly monocytes and macrophages, still remains to be elucidated. We examined the effect of periostin on monocytes and monocyte-derived macrophages (MDM) in the pathogenesis of SSc. The modified Rodnan total skin thickness score in patients with dcSSc was positively correlated with the proportion of CD80-CD206+ M2 cells. The proportion of M2 macrophages was significantly reduced in rPn-stimulated MDMs of HCs compared to that of SSc patients. The mRNA expression of pro-fibrotic cytokines, chemokines, and ECM proteins was significantly upregulated in rPn-stimulated monocytes and MDMs as compared to that of control monocytes and MDMs. A similar trend was observed for protein expression in the respective MDMs. In addition, the ratio of migrated cells was significantly higher in rPn-stimulated as compared to control monocytes. These results suggest that periostin promotes inflammation and fibrosis in the pathogenesis of SSc by possible modulation of monocytes/macrophages.

Risks of malignancies among patients with psoriasis: A cohort study of 360 patients.

Psoriasis is a systemic, chronic, immunologically-mediated disease affecting approximately 2%-4% of the worldwide population. It is well known that psoriasis is associated with several comorbidities such as metabolic syndrome, cardiovascular disease, and malignancy. Although meta-analyses and large prospective cohort studies have shown an increased risk of malignancies in patients with psoriasis worldwide, an association between psoriasis and malignancy onset has not yet been established in Japan. We retrospectively analyzed 360 patients with psoriasis at our hospital to evaluate the incidence and types of malignancies in these patients. The incidence rate of malignancy was 14.4% (52/360). Colorectal cancer was the most commonly associated malignancy (20.9%), followed by skin cancer (16.4%), gastric cancer (10.4%), and lung cancer (10.4%). The calculated age- and sex-standardized incidence ratio of malignancies was 1.235 (95% CI 0.952-1.601) which indicated that the malignancy rate was higher in patients with psoriasis than in the general population, although the difference was not statistically significant. Furthermore, the multivariate analysis revealed increased risk of malignancy in males (HR = 3.15; 95% CI 1.381-7.187; p < 0.001), psoriasis onset at older age (HR = 1.08; 95% CI 1.058-1.111; p < 0.01), and psoriatic erythroderma (HR = 4.44; 95% CI 1.354-14.581; p < 0.05). We also observed that treatment with biological agents tends to reduce the risk of developing malignancy; however, no statistical significance was found. These results suggest that periodic screening for malignancy should be recommended in patients with psoriasis having these risk factors and in those with poorly controlled psoriatic inflammation.

Abnormal inflammatory traits and downregulated caveolin-1 expression in monocytes of psoriasis patients may be associated with psoriatic inflammation and atherosclerosis.

BACKGROUND: Monocytes and macrophages are implicated in inflammation and atherosclerosis, whereas monocytes are involved in psoriasis lesion formation. We previously reported a psoriatic inflammation-associated significant decrease in the membrane protein caveolin-1 (CAV-1) in psoriasis patient monocytes. However, the phenotype of circulating monocytes and their macrophage differentiation in psoriasis patients remain unclear. OBJECTIVE: We sought to clarify circulating monocyte and monocyte-derived macrophage (MDM) phenotypes in psoriasis patients with and without comorbidities. METHODS: Thirty-one patients with psoriasis vulgaris and 28 control subjects were included. Surface macrophage markers and inflammatory status were examined in circulating monocytes and MDMs from both groups. Expression of CD36, which mediates macrophage uptake of oxidized low-density lipoprotein (oxLDL), was evaluated in these cells. CAV-1-silenced monocytes were differentiated into macrophages to investigate the effects of CAV-1 downregulation on psoriatic inflammation and atherosclerosis. RESULTS: Macrophage surface markers were detectable in circulating monocytes. A significant M1 shift was detected in monocytes and MDMs in psoriasis patients, including those without cardiovascular disease risk factors, as compared to controls. MDMs of psoriasis patients had more CD36-expressing cells, which are associated with atherosclerosis risk. Additionally, CAV-1-silencing in monocytes increased the likelihood of M1-biased macrophage differentiation and increased pro-inflammatory cytokine production. CONCLUSIONS: Monocytes from psoriasis patients were more likely to differentiate into M1-dominant macrophages, correlating with inflammatory status and CAV-1 expression. These aberrant inflammatory monocytes not only contribute to psoriatic inflammation by producing psoriatic cytokines, but also have a phenotype that could increase atherosclerosis risk by uptake of oxLDL and formation of foam cells.

Downregulated IRF8 in Monocytes and Macrophages of Patients with Systemic Sclerosis May Aggravate the Fibrotic Phenotype.

Monocytes and macrophages may be involved in the pathogenesis of systemic sclerosis (SSc); however, the etiology and regulation of monocyte and macrophage function in SSc remain unknown. IRF8 is a transcriptional regulator that is essential for the differentiation and function of monocytes and macrophages and thus may be involved in the regulation of macrophage phenotypes in SSc fibrosis. In this study, we measured IRF8 levels in circulating monocytes of 26 patients with SSc (diffuse cutaneous SSc, n = 11; limited cutaneous SSc, n = 15) and 14 healthy controls. IRF8 levels were significantly suppressed in monocytes of patients with diffuse cutaneous SSc and correlated negatively with the modified Rodnan total skin thickness score. Next, we assessed expression levels of cell surface markers, cytokine profiles, and components of extracellular matrix in IRF8-silenced monocyte-derived macrophages. IRF8-silenced monocyte-derived macrophages displayed an M2 phenotype and significantly upregulated mRNA and protein levels of profibrotic factors and extracellular matrix components. Finally, we assessed skin fibrosis in myeloid cell-specific IRF8 conditional knockout (Irf8flox/flox; Lyz2Cre/+) mice and found upregulated mRNA levels of extracellular matrix components and increased bleomycin-induced skin fibrosis. In conclusion, altered IRF8 regulation in monocytes and macrophages may be involved in SSc pathogenesis.

Downregulated Caveolin-1 expression in circulating monocytes may contribute to the pathogenesis of psoriasis.

Caveolin-1 (CAV-1) is the principal component of caveolae that regulates a variety of signaling molecules and receptors. Our previous study revealed CAV-1 reduction in the epidermis of patients with psoriasis, which leads to enhanced Janus kinase/signal transducer and activator of transcription activation and cytokine production, suggesting that aberrant CAV-1 expression may contribute to psoriatic inflammation. This study aimed to investigate whether abnormal modulation of CAV-1 on immune cells is involved in the pathogenesis of psoriasis. We observed that CAV-1 level in psoriasis patients was apparently reduced in peripheral blood mononuclear cells (PBMCs) and it was prominent in CD14+ monocytes. CAV-1 silencing in monocytes represented elevated levels of interleukin (IL)-1ß and IL-6, and those had enhanced chemotaxis activity. In a murine model of psoriasis-like inflammation induced by imiquimod, we observed a significant CAV-1 reduction in PBMCs. Systemic administration of CAV-1 scaffolding domain peptide significantly improved the skin phenotype with less macrophage infiltration. Taken together, aberrant CAV-1 expression in monocytes may be involved in the pathogenesis of psoriasis.