46 research outputs found
Stevens-Johnson syndrome and toxic epidermal necrolysis: 11-year retrospective experience in a high-complexity tertiary hospital in Milan, Italy
No full textStevens-Johnson syndrome (SJS) and toxic epidermal necrolysis (TEN) are severe drug-induced hypersensitivity reactions characterized by widespread epidermal necrosis, mucous membrane erosions, and systemic findings. We have provided our 11-year experience from a Milan, Italy tertiary hospital managing SJS/TEN, evaluating the clinical and histopathologic features plus the impact on mortality. We retrospectively analyzed 28 patients diagnosed with SJS/TEN based on the clinical and histopathologic findings, according to the classification criteria of multiple studies. We assessed the dermatographics, comorbidities, drug history, lesion characteristics, clinical findings, treatments, blood tests, and outcomes. Severity scores (SCORTEN, Re-SCORTEN, ABCD-10) were used for treatment evaluation and mortality prediction. Data were statistically analyzed, and significant factors associated with mortality were identified. We found that among the 28 patients, 89.2% had comorbidities, mainly cardiovascular diseases, and 21.4% had autoimmune disorders. All patients had received systemic therapy (46.6% monotherapy, 53.6% combination therapy), with systemic steroids (71.4%) and intravenous immunoglobulins (67.8%) being common treatments. There were complications, including systemic infections (67.9%) and septic shock (10.7%). The overall mortality rate was 17.8%. The statistical analysis indicated that malignancy, a high ABCD-10 score, and a high neutrophil-to-lymphocyte ratio were significantly associated with mortality. The extent of affected body surface area did not correlate significantly with mortality. This study provides insights into SJS/TEN management, revealing factors influencing mortality in a high-complexity tertiary hospital setting
Suspected breast implant rupture: our experience, recommendations on its management and a proposal for a model of informed consent
No full textMorphological analysis of JAK1 intracellular pathway activation after pro-inflammatory psoriatic cytokines exposure: inside-out and outside-in the epidermis
No full textFor their normal growth, cells depend on a continuous flow of signals from the environment. The Janus kinases (JAK) 1 transducers signalling pathway is a pleiotropic cascade used to transduce a multitude of signals among cells. A variety of ligands including cytokines, hormones, growth factors, and their receptors stimulate the JAK1 pathway. Cytokines, a large and very heterogeneous family of small and generally soluble glycoproteins, both control multiple biological processes as haematopoiesis, inflammation, and immunity playing a central role in cell-cell communication. Their action is mediated by the binding to specific receptors on the cell surface, thus transducing biological information to target cells [1]. Pro-inflammatory cytokines play a pivotal role in several inflammatory illnesses including psoriasis. Among them, interleukin (IL)-17, IL-22, IL-23 and tumor necrosis factor (TNF)-alpha play a central role. In the formation and progression of the psoriatic lesion a typical marker is keratin (K) 17 which is correlated with psoriasis severity. The aims of this study were to evaluate the early, direct, and specific effects of pro-inflammatory psoriatic cytokines i) on the activation of the intracellular pathway JAK1 and ii) on the correlation with the induction of K17 expression in a three-dimensional model (3D) of human skin (n=7) by immunofluorescence. Biopsies were cultured overnight epidermal side-up in a Transwell system and exposed to 50 ng/ml IL-17, or 100 ng/ml IL-22, or 50 ng/ml IL-23 or 100 ng/ml TNF-alpha. Samples were harvested 24 (T24), 48 (T48), and 72 (T72) hours after cytokine incubation.
In samples not exposed to cytokines, a JAK1 slight labelling was observed throughout the epidermis, decreasing at T72 in the lower layers. At T24, IL-17 and IL-22, but not IL-23 and TNF-alpha, induced an expression of JAK1 in the spinous layer. At T72, JAK1 immunostaining decreased in all samples, similarly to controls. K17 immunopositivity was induced and progressively increased with time in the suprabasal layers of epidermis in all experimental groups, with the exception of the TNF-alpha group. These results suggest that cytokines exert parallel effects on JAK1 pathway activation and K17 induction.
In conclusion, 3D this model, reproducing some features of psoriatic microenvironment, represents a useful experimental approach to dissect the specific role of each cytokine in the different steps of psoriatic lesion formation
Il lembo osteomuscolare di temporale nella riparazione dei gravi difetti della mandibola.
No full textEffect of TNF-alpha and IL-17 on TLR expression and Langerhans cells phenotype in a three-dimensional model of normal human skin: a morphological study
No full textToll-like receptors (TLRs) are essential for innate immunity and contribute to create the skin barrier. Their abnormal stimulation is involved in the development of several dermatological diseases, among which psoriasis. Tumor Necrosis Factor (TNF)-alpha and interleukin (IL)-17 play a pivotal role in the pathogenesis of psoriatic plaques and their proinflammatory activity can affect Langerhans cell (LC) phenotype. In a well characterized three-dimensional model of organotypic cultures of normal human skin [1-3] we evaluated the effect of TNF-alpha and IL-17 on the expression of TLR2 and 9 by immunofluorescence, on the ultrastructural morphology of keratinocytes and LCs by transmission electron microscopy (TEM). Human skin explants (n=7) were cultured at the air-liquid interface overnight in a Transwell system and exposed to 50 ng/ml IL-17 or 100 ng/ml TNF-alpha or a combination of both cytokines. Samples were harvested 24 (T24) and 48h (T48) after cytokines incubation. After incubation with IL-17 and IL-17+TNF-alpha, TLR2 immunostaining was not detectable in the basal layer, differently from controls and TNF-alpha-treated samples. Conversely, TLR9 expression was progressively induced in granular keratinocytes in all cytokine-exposed groups. By TEM, enlargements of intercellular spaces were evident especially and, after IL-17 treatment, LCs showed an activated phenotype. At T24 LCs number increased indicating that TNF-alpha and IL-17+TNF-alpha exert a chemoattractant activity, while at T48 only IL-17+TNF-alpha maintained this effect on trapping LCs in epidermis. TNF-alpha and IL-17 differently affect LCs behaviour and TLR expression, with a specific contribution to the inflammatory loop underlying the lesion formation. The simultaneous inhibition of the effect of different cytokines - all with a defined role in the pathogenesis of psoriasis - could further improve psoriasis treatment
Tumour necrosis factor-alpha and interleukin-17 differently affects Langerhans cell distribution and activation in an innovative three-dimensional model of normal human skin
No full textAmong the several cytokines involved in the psoriasis pathogenesis, tumor necrosis factor (TNF)-alpha and interleukin (IL)-17 play a central role. Many biomolecular steps remain unknown due to difficulty to obtain psoriatic models. To investigate the effect of TNF-alpha and IL-17 on the ultrastructure, immunophenotype, and number of epidermal Langerhans cells (LCs), human skin explants (n=7) were cultured air-liquid interface in a Transwell system. Four different conditions were used: medium alone (control), medium added with 100 ng/ml TNF-alpha or 50 ng/ml IL-17 or a combination of both cytokines. Samples were harvested 24 and 48 h after cytokine addition and were frozen. Samples harvested at 24h were also processed for transmission electron microscopy (TEM). By immunofluorescence analysis with anti-human Langerin antibody (three experiments/sample) we calculated the percentage of LCs/mm(2) of living epidermis after 24 and 48 h of incubation (considering control as 100%). At 24h LC number was significantly higher in samples treated with both cytokines (216.71+15.10%; p<0.001) and in TNF-alpha (125.74+26.24%; p<0.05). No differences were observed in IL-17-treated samples (100.14+38.42%). After 48 h, the number of epidermal Langerin-positive cells in IL-17- and TNF-alpha treated samples slightly decreased (94.99+36.79% and 101.37+23% vs. their controls, respectively). With the combination of both cytokines epidermal LCs strongly decreased (120+13.36%). By TEM, upon TNF-alpha stimulus LCs appeared with few organelles, mostly mitochondria, lysosomes, and scattered peripherical BGs. Upon IL-17 stimulus, LCs showed a cytoplasm with many mitochondria and numerous BGs close to the perinuclear space and Golgi apparatus, but also at the periphery, at the beginning of the dendrites. The addition of both cytokines did not affect LC ultrastructure. Our study showed that IL-17 induced significant changes in LC ultrastructure, while the combination of both cytokines seems to have a strong chemo-attractant effect on epidermal LCs, supporting the relevance of investigating the interplay between LCs and pro-inflammatory cytokines in the ongoing of the disease
Langerhans cells and Toll Like Receptors: how do they act and react in an in vitro psoriatic microenvironment?
No full textTumor Necrosis Factor (TNF)-α, interleukin (IL)-17, IL-22 and IL-23 are involved in the psoriasis pathogenesis and represent a strong proinflammatory stimulus. Both epidermal keratinocytes (KCs) and Langerhans cells (LCs) early respond promoting an early epidermal response [1, 2]. Human skin can count on the cellular response supported by LCs and on innate immunity through the expression of Toll-like Receptors (TLRs) [4]. We aimed at investigate whether the exposure of normal human skin to a combination of TNF-α, IL-17, IL-22, and IL-23 (cytokine mix) affected i) LCs immunophenotype, ii) expression of TLR2 and TLR9 and iii) KC proliferation. Human skin samples were obtained after plastic surgery (n = 5) and exposed to the cytokine mix in a Transwell system at air-liquid interface, with a parallel control group. Samples were harvested 24 and 48 hours after cytokine stimulation, processed in parallel for immunofluorescence or ultrastructural analysis. A decrease of cell proliferation was evident in samples exposed to cytokine mix for 24 hours and this phenomenon was more and more evident later. TLR2 immunopositivity progressively disappeared in the basal layer after cytokine mix exposure compared to the control group, while TLR9 expression was induced in scattered granular keratinocytes. By TEM, LCs showed an activated phenotype. In conclusion, these results suggest that, in a microenvironment mimicking the psoriatic plaque, epidermis early stimulates two important lines of defense, thus proposing that a therapeutic intervention in this direction can interfere with the formation/progression of the psoriatic plaque
A proinflammatory microenvironment induces NFkB activation and beta-defensin expression through specific Toll Like Receptors in a 3D human skin model
No full textPsoriasis is an autoimmune skin disease characterized by the formation and the progression of silvery plaques on the extensory surfaces of our body. Proinflammatory cytokines as Tumor Necrosis Factor (TNF)-alpha, interleukin (IL)-17, IL-22 and IL-23 represent for the normal skin a psoriatic microenvironment. In the 3D human skin model standardized in our lab in the last decade, we were able to dissect the events in which each cytokine exerts a specific effect, e.g. keratinocyte proliferation, Langerhans cell activation, cytoskeleton arrangement, and, more recently, the epidermal expression of Toll like Receptors (TLRs) 2, 7, 9. Several experimental studies reported that in psoriasis TLRs are expressed and their activation triggers i) NFkB translocation from the cytoplasm to the nucleus and ii) the release of beta defensins (HBDs). The present study was aimed at investigating the intracellular NFkB activation and HBD1 and HBD2 expression induced by a cytokine mix (TNF-alpha, IL-17, IL-22, IL-23) by indirect immunofluorescence. Bioptic samples of normal human skin were obtained after aesthetic surgery of young healthy informed women (n=7). After overnight incubation to reduce mechanical and termical stress, skin fragments were incubated in a Transwell system for 5 (T5), 24 (T24), and 48 (T48) hours with the cytokine mix. Parallel control samples were carried out and each patient was represented at all time points. In controls at all time-points NFkB was localized only in the cytoplasm, while, starting from T5, scattered basal nuclei were observed in the cytokine-incubated samples. At later time points, in the upper spinous and granular layers, NFkB nuclear immunostaining was evident. HBD2 expression was affected after cytokine mix exposure, while HBD1 distribution was similar to controls.
Thanks to this simple but effective model, a deep knowledge of the early events occurring in the normal epi-dermis exposed to cytokines can be achieved, excluding the contribution of the blood and lymphatic vessels herein absent. This basic research can thus represent an important tool for targeting and counteracting single phenomenon leading to the formation/progression with the most innovative biological drugs
Ultrastructural study of the effect of proinflammatory cytokines in a three-dimensional model of normal human skin
No full textPsoriasis is an autoimmune disease in which epidermal keratinocytes and innate immunity effector cells play a pivotal role in the lesion formation. Tumor necrosis factor (TNF)-alpha and interleukin (IL)-17 are known to play a relevant role in the immunological activation typical of psoriasis, but the mechanisms leading to disease are still poorly known.
Several experimental models are available, but all of them have intrinsic limitations. A three dimensional model of organotypic human skin culture is a valuable approach for exposing the whole skin to TNF-alpha and IL-17 as specific proinflammatory stimuli mimicking a psoriatic microenvironment. To gain insight on the action of these cytokines on human skin, the present study was carried out in such a model, standardized in our laboratory, looking at the direct and immediate effects of proinflammatory cytokines on the ultrastructure of normal human epidermis. Normal human skin explants were obtained from plastic surgery of healthy 20-40 year-old women (n = 7) after informed consent. Bioptic fragments were cultured overnight in Dulbecco's modified minimum Eagle's medium and further divided before adding either 100 ng/ml TNF-alpha or 50 ng/ml IL-17 or a combination of both cytokines. Samples were harvested 24 hours after cytokine incubation and processed for transmission electron microscopy. Each patient was represented in all experimental groups. At light microscopy observation of semithin sections, the skin three-dimensional architecture appeared unaffected by cytokine treatment. By electron microscopy, the basal compartment of cytokine-treated samples presented a monolayer of cylindrical keratinocytes accompanied by melanocytes, as in normal skin, but occasional cells showed signs of ongoing apoptosis. Desmosomes were uniformly distributed throughout the epidermis. Langerhans cells were present and rich in Birbeck granules. A few dermal cells near the epidermis were well preserved, while more deeply located cells appeared apoptotic or necrotic. After cytokine treatment the intercellular spaces were enlarged in the basal and spinous layer, especially upon TNF-alpha, but desmosomes were still present; Langerhans cells appeared as in controls.
These results suggest that in these experimental conditions neither TNF-alpha nor IL-17 affect the epidermal architecture and cell ultrastructure, but the intercellular oedema suggests that the two proinflammatory cytokines can exert early and direct effects on normal human epidermal keratinocytes
Morphological features induced by interleukin 17 in a 3D organotypic cultures of normal human skin are promptly reverted by specific biological inhibitor
No full textPsoriatic plaque is the result of a strict interaction among epidermal cells, immune system, and soluble cytokines. Interleukin 17 (IL-17) is a well-known proinflammatory psoriatic cytokine mainly produced by the T helper subclass Th17. In the last decade we standardized a 3D model organotypic cultures of normal human skin for studying the early, intrinsic and specific effects induced by IL-17. We demonstrated that IL-17 elicited Langerhans cell (LC) activation and migration, keratin 17 expression, Toll like receptor 7 and 9 expressions and profoundly altered filaggrin expression, without affecting the suprabasal distribution of keratin 10 and keratin 14. Moreover, this cytokine early inhibited keratinocyte proliferation, strongly suggesting that this event can be the basis for the response to injury leading to the psoriatic characteristic hyperproliferation observed in lesional plaques. In the present study, we incubated bioptic skin fragments obtained after aesthetic surgery of healthy young women (n=5) with i) IL-17 alone, ii) with a combination of IL-17 and an IL-17 biological inhibitor, iii) with the IL-17 biological inhibitor alone. Control samples were in parallel cultured. Incubation lasted for 24 and 48 hours with skin at the air-liquid interface. Immunofluorescence experiments and transmission electron microscopy (TEM) analysis were carried out. Samples incubated with the IL-17 biological inhibitor were comparable to controls. By immunofluorescence, the combination reverted IL-17-induced effects at all considered time-points. By TEM, LCs appeared less activated as shown by the paucity of Birbeck granules and the highly dispersed nuclear chromatin. The epidermal ultrastructure was comparable in all groups, with well-preserved desmosomes, interspersed keratin filaments and terminally differentiated granular keratinocytes/corneocytes. These results highlight the clinical usefulness of this experimental approach for identifying the early psoriatic processes that can be modulated by last generation biological agents
