Epidermal expression of 65 and 72 kd heat shock proteins in psoriasis and AIDS-associated psoriasiform dermatitis

The Role of Alarmins in the Pathogenesis of Rheumatoid Arthritis, Osteoarthritis, and Psoriasis

Alarmins are immune-activating factors released after cellular injury or death. By secreting alarmins, cells can interact with immune cells and induce a variety of inflammatory responses. The broad family of alarmins involves several members, such as high-mobility group box 1, S100 proteins, interleukin-33, and heat shock proteins, among others. Studies have found that the concentrations and expression profiles of alarmins are altered in immune-mediated diseases. Furthermore, they are involved in the pathogenesis of inflammatory conditions. The aim of this narrative review is to present the current evidence on the role of alarmins in rheumatoid arthritis, osteoarthritis, and psoriasis. We discuss their potential involvement in mechanisms underlying the progression of these diseases and whether they could become therapeutic targets. Moreover, we summarize the impact of pharmacological agents used in the treatment of these diseases on the expression of alarmins.

Desired response to phototherapy vs photoaggravation in psoriasis: what makes the difference?

Psoriasis commonly responds beneficially to UV radiation from natural sunlight or artificial sources. Therapeutic mechanisms include the proapoptotic and immunomodulating effects of UV, affecting many cells and involving a variety of pro- and anti-inflammatory cytokines, downregulating the Th17/IL-23 response with simultaneous induction of regulatory immune cells. However, exposure to UV radiation in a subset of psoriasis patients leads to exacerbation of the disease. We herein shed light on the predisposing factors of photosensitive psoriasis, including genetics (such as HLA-Cw*0602 or CARD14), gender and coexisting photodermatoses such as polymorphic light eruption (PLE) in the context of potential molecular mechanisms behind therapeutic photoresponsiveness or photoaggravation. UV-induced damage/pathogen-associated molecular patterns, damage to self-coding RNA (signalling through Toll-like receptors), certain antimicrobial peptides and/or inflammasome activation may induce innate immunity, leading to psoriasis at the site of UV exposure when there is concomitant, predisposing resistance against UV-induced suppression of the adaptive immune response (like in PLE) that otherwise would act to reduce psoriasis.

Diffuse HIV-associated seborrheic dermatitis - a case series

Seborrheic dermatitis (SD) is reported to have distinct clinical and histologic presentations in patients with HIV infection. Here we present 20 cases to further define some of these unique characteristics. Common features include erythematous, scaly papules, and plaques involving areas beyond the typical seborrheic distribution; thick, greasy scale on the scalp; and an increased frequency of erythroderma. Histologically, there is widespread parakeratosis, spongiosis, and necrotic keratinocytes. Treatment is often difficult, requiring prolonged use of oral and topical antifungals and corticosteroids as well as antibiotics for bacterial superinfection. SD with these features represents a marker for HIV infection and can aid in early diagnosis.

The Malassezia genus in skin and systemic diseases

In the last 15 years, the genus Malassezia has been a topic of intense basic research on taxonomy, physiology, biochemistry, ecology, immunology, and metabolomics. Currently, the genus encompasses 14 species. The 1996 revision of the genus resulted in seven accepted taxa: M. furfur, M. pachydermatis, M. sympodialis, M. globosa, M. obtusa, M. restricta, and M. slooffiae. In the last decade, seven new taxa isolated from healthy and lesional human and animal skin have been accepted: M. dermatis, M. japonica, M. yamatoensis, M. nana, M. caprae, M. equina, and M. cuniculi. However, forthcoming multidisciplinary research is expected to show the etiopathological relationships between these new species and skin diseases. Hitherto, basic and clinical research has established etiological links between Malassezia yeasts, pityriasis versicolor, and sepsis of neonates and immunocompromised individuals. Their role in aggravating seborrheic dermatitis, dandruff, folliculitis, and onychomycosis, though often supported by histopathological evidence and favorable antifungal therapeutic outcomes, remains under investigation. A close association between skin and Malassezia IgE binding allergens in atopic eczema has been shown, while laboratory data support a role in psoriasis exacerbations. Finally, metabolomic research resulted in the proposal of a hypothesis on the contribution of Malassezia-synthesized aryl hydrocarbon receptor (AhR) ligands to basal cell carcinoma through UV radiation-induced carcinogenesis.

New insights into HIV-1-primary skin disorders

Since the first reports of AIDS, skin involvement has become a burdensome stigma for seropositive patients and a challenging task for dermatologist and infectious disease specialists due to the severe and recalcitrant nature of the conditions. Dermatologic manifestations in AIDS patients act as markers of disease progression, a fact that enhances the importance of understanding their pathogenesis.

Broadly, cutaneous disorders associated with HIV type-1 infection can be classified as primary and secondary. While the pathogenesis of secondary complications, such as opportunistic infections and skin tumours, is directly correlated with a decline in the CD4⁺ T cell count, the origin of the certain manifestations primarily associated with the retroviral infection itself still remains under investigation.

The focus of this review is to highlight the immunological phenomena that occur in the skin of HIV-1-seropositive patients, which ultimately lead to skin disorders, such as seborrhoeic dermatitis, atopic dermatitis, psoriasis and eosinophilic folliculitis. Furthermore, we compile the latest data on how shifts in the cytokines milieu, impairments of the innate immune compartment, reactions to xenobiotics and autoimmunity are causative agents in HIV-1-driven skin diseases. Additionally, we provide a thorough analysis of the small animal models currently used to study HIV-1-associated skin complications, centering on transgenic rodent models, which unfortunately, have not been able to fully unveil the role of HIV-1 genes in the pathogenesis of their primarily associated dermatological manifestations.

Animal models of psoriasis

Psoriasis is a common and chronic skin disorder under active investigation around the world. Despite this, determination of its genetic basis, role of the immune system in the disease pathophysiology and development of effective therapy, have been hampered severely by the absence of any spontaneous psoriatic skin disease in animals. Furthermore, until recently, validated animal models designed to create psoriasis were unavailable to investigative skin biologists and clinical scientists. However, there is at least one animal model which has been established and validated; it uses human skin engrafted on to severe combined immunodeficient (SCID) mice. In addition, there are several other rodent models which do not involve transplantation technology that share some (but not all) features in common with psoriasis. This review will summarise these available animal models and critique their relevance with respect to illuminating the immunogenetic basis of psoriasis and their value in screening novel treatments in a preclinical setting.

Expression of cutaneous lymphocyte-associated antigen (CLA) in tonsillar T-cells and its induction by in vitro stimulation with alpha-streptococci in patients with pustulosis palmaris et plantaris (PPP)

Pustulosis palmaris et plantaris (PPP) is known to be a one of the tonsil-related diseases because tonsillectomy is quite effective in curing this condition. However etiological association between tonsils and PPP have not fully clarified yet. Cutaneous lymphocyte-associated antigen (CLA) is known to be a specific homing receptor that facilitates T-cell migration into skin. In this study, we investigated the expression of CLA on T-cells in tonsil, peripheral blood, and skin from patients with PPP. Two-color flow cytometric and two-color immunohistological analyses revealed that the numbers of CLA/CD3 double-positive cells in freshly isolated tonsillar mononuclear cells (TMC) and in tonsillar tissues were significantly higher in patients with PPP than in patients without PPP (P<0.01, each). In vitro stimulus with alpha-streptococcal antigens enhanced CLA expression of tonsillar T-cells and TGF-beta production of TMC in patients with PPP (P<0.01, each), but did not in patients without PPP. In peripheral blood from PPP patients, the number of the CLA/CD3 double-positive cells significantly decreased at 6 months after tonsillectomy (P<0.05). The CLA/CD3 double-positive cells and the postcapillary venule that expressed with a ligand of CLA, E-selectin, were found more frequently in the plantar skin from patients with PPP as compared to that from healthy volunteers (P<0.01, each). These data suggest that a novel immune response to alpha-streptococci may enhance CLA expression on tonsillar T-cells through TGF-beta production in patients with PPP, resulting in moving of CLA-positive tonsillar T-cells to skin and tissue damages. This may play a key role in pathogenesis of PPP.

Heat shock proteins 60 and 70 expression of cutaneous lichen planus: comparison with normal skin and psoriasis vulgaris*

BACKGROUND

Heat shock proteins (HSPs) are expressed by most living cells and play fundamental roles in many biological processes. Their synthesis increases by a variety of stresses in order to enable cellular survival. Although it is known that they play an important role in immune and inflammatory responses of the skin, the role of HSPs in the pathogenesis of skin diseases has been studied in only limited skin diseases. Lichen planus (LP) is a relatively common papulosquamous dermatosis, and cell-mediated immunity plays an important role in its pathogenesis. Although an altered expression of certain HSPs was reported in oral LP lesions, the expression of HSPs in cutaneous lesions of LP has not been investigated. In this immunohistochemical study, we aimed at investigating the role of HSPs in the pathogenesis of LP by studying whether there is any difference in HSP expression in cutaneous lesions of LP when compared to normal skin and psoriasis vulgaris (PV).

METHODS

Formalin-fixed paraffin-embedded skin biopsy specimen blocks from LP patients (n = 39), patients with psoriasis (n = 20), and normal skin controls (n = 20) were used in the study. Antibodies to HSPs 60 and 70 were applied immunohistochemically by using streptavidin-biotin-horseradish peroxidase complex. An immunoreactivity intensity distribution index (IRIDI) was calculated to express the proportion of the immunoreactive cells as well as the staining intensity in different layers of the epidermis.

RESULTS

The mean IRIDI scores for HSP60 expression in the basal, suprabasal, and superficial epidermal layers of cutaneous LP were moderately higher than those of normal skin, but not different from those of PV skin. These scores for HSP70 in lesions of LP were moderately lower than those for normal skin in the basal layer, but not significantly different from normal in the other two layers. Scores for HSP70 in PV lesions were markedly lower in all three layers. In the cells of the inflammatory infiltrates (mostly lymphocytes), HSP60 scores for LP were moderately higher, compared to those for PV, whereas scores for HSP70 were much lower for LP and very much lower for PV.

CONCLUSIONS

Significantly altered levels of HSP proteins were found in cutaneous LP lesions in comparison with normal skin and psoriasis, suggesting the role of HSPs in the pathogenesis of LP.

Possible role of Malassezia furfur in psoriasis: modulation of TGF-beta1, integrin, and HSP70 expression in human keratinocytes and in the skin of psoriasis-affected patients

BACKGROUND

Psoriasis is a disease characterized by an abnormal pattern of keratinocyte growth and differentiation. Malassezia furfur forms part of the normal human skin flora. It may also be involved in the pathogenesis of psoriasis. To define the role of M. furfur in the pathogenesis of psoriasis, we investigated how M. furfur regulates molecules involved in cell migration and proliferation. The experiments were performed using human keratinocytes and skin biopsies from M. furfur-positive and -negative psoriasis-affected patients. In addition, we examined the signal transduction mechanisms involved.

MATERIALS AND METHODS

Western blot analysis was performed on human keratinocytes lysates treated or untreated with M. furfur and on biopsies from healthy and psoriasis patients. Signal transduction mechanisms involved were evaluated by electrophoretic mobility shift assay using the AP-1 inhibitor curcumin.

RESULTS

We found that M. furfur up-regulates transforming growth factor-beta1 (TGF-beta1), integrin chain, and HSP70 expression in human keratinocytes via AP-1-dependent mechanism. In the biopsies of M. furfur-positive psoriasis-affected patients, an increase in TGF-beta1, integrin chains, and HSP70 expression was found.

CONCLUSION

Our data suggest that M. furfur can induce the overproduction of molecules involved in cell migration and hyperproliferation, thereby favoring the exacerbation of psoriasis.

IgG class antibodies from psoriasis patients recognize the 60-KDa heat-shock protein of Streptococcus pyogenes

BACKGROUND

We have previously found that psoriatic patients have IgG autoantibodies that recognize lesions but not autologous normal skin. The reactivity of the autoantibodies can be adsorbed with streptococcal antigens.

METHODS

IgG antibodies were determined by immunoblot and ELISA to streptococcal antigens and by ELISA to the recombinants HSP60Sp, HSP70Sp, HSP60Ec and HSP60Hu, in plaque (PP) and guttate (GP) psoriasis patients, in healthy subjects (HC) and in individuals with streptococcal throat infections and high ASO titers, but without history of dermatological disease (ISp).

RESULTS

We found by immunoblot that the IgG response to 71-, 60-, and 14-kDa protein fractions of Streptococcus pyogenes is important in psoriasis. We also found by ELISA that the response to the rHSP60Sp in PP was higher than in all the other three groups studied (P < 0.05) with an odds ratio of 11.11 (CI95% of 4.33-28.49). The PP infected with S. pyogenes had higher titers of the antirHSP60Sp, high ASO, and high PASI. The PP patients did not significantly recognize the HSP60Ec or the HSP60Hu. The GP patients had a higher response to the rHSP60Sp than the healthy controls or ISp patients (P < 0.05) but showed no association with the disease. The response of the ISp patients to the HSP60Sp was similar to the healthy controls. The response to the rHSP70Sp was similar in the PP patients and the healthy controls.

CONCLUSION

Results suggest that a high response to the HSP60Sp could be associated with the chronic form of psoriasis.

Seborrheic dermatitis

Seborrheic dermatitis is a common inflammation of the skin, occurring most often on the face, scalp and chest. It is closely related to infantile seborrheic dermatitis, or diaper rash. Seborrheic dermatitis is particularly common in patients with Parkinson's disease or with HIV/AIDS. The recent resurgence of interest in Malassezia yeasts has revived the old hypothesis that seborrheic dermatitis is caused by an altered relationship between these skin commensals and the host. Moreover, the success of antifungal medications in treating seborrheic dermatitis provides new evidence for this view.

LEARNING OBJECTIVE

Upon completing this paper, the reader should be aware of the clinical presentation of seborrheic dermatitis and which populations are at particular risk of developing this disorder. In addition, s/he will be aware of the role of Malassezia yeasts in seborrheic dermatitis and the way in which knowledge of the importance of these yeasts has altered the treatment of this disorder.

Seborrheic dermatitis

Seborrheic dermatitis is present in 1% to 3% of immunocompetent adults, and is more prevalent in men than in women. Seborrheic dermatitis may be seen in conjunction with other skin diseases, such as rosacea, blepharitis or ocular rosacea, and acne vulgaris. Malassezia yeasts have been associated with seborrheic dermatitis. Abnormal or inflammatory immune system reactions to these yeasts may be related to development of seborrheic dermatitis. Treatment modalities for seborrheic dermatitis include keratolytic agents, corticosteroids, and more recently, antifungal agents. Antifungal agents do not carry a risk of skin atrophy or telangiectasia with prolonged use, and it is more prudent to consider antifungals than corticosteroid preparations. The wide range of antifungal formulations available (creams, shampoos, or oral) provides safe, effective, and flexible treatment options for seborrheic dermatitis.

IgG class antibodies to heat shock-induced streptococcal antigens in psoriatic patients

BACKGROUND

Psoriasis is a chronic inflammatory skin disease. Probably autoimmune in nature, and associated with streptococcal throat infections as a triggering factor. Although many groups have associated the disease with other pathogens, Streptococcus pyogenes seems to be the most important microorganism related to this disease. Therefore, it is necessary to identify the streptococcal antigens involved in the process.

METHODS

In this work IgG class antibodies to soluble antigens obtained from Staphyloccus aureus, Candica albicans or S. pyogenes before and after heat shock induction, were analyzed by ELISA in 28 psoriatic patients and 30 healthy donors.

RESULTS

In all cases, the patients and the controls had IgG class antibodies to the four antigens. Nevertheless, the IgG levels to the heat shock-induced S. pyognes were statistically different between the patients and the controls (P < 0.001). There was no difference between the groups when the IgG antibodies to the other antigens, including the noninduced streptococcal extract, were analyzed. Additionally, anti-streptolysin O titers and throat cultures were carried out in all patients and controls. No differences between ASO titers were found but the patients were more frequently colonized by pyogenes.

CONCLUSION

Results obtained in this study suggest that heat shock-induced proteins from S. pyogenes are associated with psoriasis.

Mechanistic perspectives on sulfonamide-induced cutaneous drug reactions

PURPOSE OF REVIEW

Idiosyncratic drug reactions continue to limit the therapeutic utility of sulfonamide drugs because of their associated morbidity and mortality. Cutaneous reactions are the predominant reasons for withdrawal of such drugs from use in patients. As a consequence of the recognized metabolic and immunologic capability of the skin, an understanding of the pathogenic role of this tissue in the development of sulfonamide-induced cutaneous drug reactions may provide insight into the mechanisms and risk factors for these and other adverse drug events.

RECENT FINDINGS

In the present review we discuss currently available mechanistic information, including issues related to drug bioactivation and adduct formation, immunoresponsiveness, and immune dysregulation, for the development of sulfonamide-induced (delayed-type) cutaneous drug reactions. The potential application of findings from several related areas of research are also discussed within the context of the pathogenesis of these cutaneous reactions.

SUMMARY

Despite progress, numerous unresolved issues support the testing of novel hypotheses, the search for additional risk factors, and the need for a global approach, including links between laboratory and clinical paradigms. These issues must be addressed if we are to gain an understanding of the mechanistic bases for these cutaneous drug reactions.

HSP 60 expression in mucocutaneous lesions of Behçet's disease

BACKGROUND

Heat shock protein (60 kd HSP) has been implicated in the etiology of Behçet's disease, but its expression at sites of inflammation is unknown.

OBJECTIVE

Our aim was to investigate local HSP 60 expression and to quantify T-cell receptor (TCR) gamma delta-positive cells, which are known to respond to HSP peptides.

METHODS

Patients with active Behçet's disease (n = 21) and controls (n = 18) were included. Flow cytometric analysis was performed on peripheral blood to investigate TCR gamma delta-positive cell counts. Biopsies were performed on active skin lesions, and immunohistochemical analysis was performed by a streptavidin-biotin method using the monoclonal ML-30 antibody; HSP staining intensity and distribution were evaluated in a blinded fashion. Immunohistochemical studies were performed to quantify TCR gamma delta-positive cells at lesional sites.

RESULTS

Mucocutaneous lesions of patients with Behçet's disease had statistically significantly increased expression of HSP 60/65. Peripheral blood TCR gamma delta-positive cell counts were similar in both groups. However, lesional skin of patients with Behçet's disease had significantly increased gamma delta-positive T-cell counts.

CONCLUSION

Up-regulation of HSP expression was found at lesional skin sites in Behçet's disease. The increased number of TCR gamma delta-positive cells, which are known to respond to HSP peptides, may support the function of HSPs in the etiology of Behçet's disease. However, these findings may also be an epiphenomenon that needs to be further investigated.

Expression of 27 KD, 65 KD and 72/73 KD heat shock protein in atopic dermatitis: comparison with those in normal skin and contact dermatitis

The expression of Heat Shock Protein (HPS) 72/73, HSP65 and HSP27 in skin lesions of atopic dermatitis (n = 21) was studied and compared with that in contact dermatitis (n = 18) and normal skin (n = 9). Keratinocytes in the whole epidermis expressed both HSP65 and HSP72/73 with a membranous, cytoplasmic or nuclear/perinuclear staining pattern much more intensely in atopic dermatitis than in contact dermatitis and normal subjects. In approximately half of the subjects with atopic dermatitis, infiltrating cells in the dermis expressed HSP65 and HSP72/73; this was not observed in contact dermatitis. HSP27 was expressed in the upper epidermis with a cytoplasmic or nuclear/perinuclear staining pattern in all groups. HSP27 was not expressed by infiltrating cells. A clinical evaluation of atopic dermatitis showed that more severe types of atopic dermatitis expressed more intense expression of HSP65 and HSP72/73, but not HSP27, in their skin lesions. These findings suggested that HSP65 and HSP72/73 may play roles in the pathogenesis of atopic dermatitis.