Erythema multiforme lesions are associated with expression of a herpes simplex virus (HSV) gene and qualitative alterations in the HSV-specific T-cell response

Erythema multiforme associated with anti-plakin antibodies: a multicentric retrospective case series

BACKGROUND

Erythema multiforme (EM) is a muco-cutaneous inflammatory disease mainly triggered by herpes simplex virus (HSV) recurrences. Association of EM and circulating auto-antibodies against plakins (anti-PLK-Abs [EM-PLK+]) has been reported. However, little is known about this subset of EM.

OBJECTIVES

We aimed to describe the clinical and immunological features and response to treatment of EM-PLK+.

METHODS

We conducted a retrospective multicentric study of EM-PLK+ selected from the database of the immunological laboratory of Bichat hospital, Paris, France, from January 2009 to December 2020. Anti-PLK-Abs were detected in ≥1 immunological tests: immunofluorescence assay, immunoblotting and/or ELISA. Patients with alternative diagnoses were excluded.

RESULTS

We included 29 patients (16 women, median age 25 [range 2-58] years). EM-PLK+ were mostly major (EM with ≥2 mucosal involvements; n = 24, 83%) and relapsing (≥2 flares; n = 23, 79%). Cutaneous lesions were target (n = 13, 54%) and target-like lesions (n = 9, 38%) with usual topography (acral, n = 19, 79%; limbs, n = 21, 88%). Mucosal lesions affected the mouth (n = 27, 96%) and genitalia (n = 19, 68%), with a median of 2 [range 0-5] mucous membranes. EM-PLK+ were suspected as certain or possible postherpetic (EM-HSV) in 19 cases (65.5%); no triggering factors were detected in 9 (31%) patients. Desmoplakin-I/II Abs were the most frequent anti-PLK-Abs (n = 20, 69%); envoplakin and periplakin Abs were detected in 11 and 9 cases. Relapsing EM-PLK+ (n = 23) were still active (≥1 flare within 6 months) in 13 (57%) patients despite immunosuppressive therapy (n = 8, 62%). Antiviral drugs were ineffective in preventing relapse in 15/16 (94%) EM-HSV.

CONCLUSION

The rationale for anti-PLK-Ab detection in EM is not elucidated. More systematic research of anti-PLK-Abs is warranted to better understand whether this association reflects humoral immune activity in a subset of EM or is fortuitous, related to an epitope spreading process. However, EM-PLK+ seems to be associated with major and relapsing subtypes, and difficult-to-treat cases.

Triggers, clinical manifestations, and management of pediatric erythema multiforme: A systematic review

BACKGROUND

Erythema multiforme (EM) is an acute inflammatory mucocutaneous condition. EM is rarely described in children and infants.

OBJECTIVE

To investigate the triggers, clinical manifestations, and treatment of pediatric EM.

METHODS

Systematic literature review of pediatric EM.

RESULTS

After full-text article review, we included 113 articles, representing 580 patients. The mean age was 5.6 years, ranging 0.1-17 years. Infectious agents were the main triggers: herpes simplex virus (HSV) in 104 patients (17.9%) and Mycoplasma pneumoniae in 91 patients (15.7%). In total, 140 cases (24.1%) were drug-related and 89 cases (15.3%) had other triggers, such as vaccines (19 patients, 3.2%). In total, 229 patients had EM major (39.5%). Treatment was supportive care only (180 patients, 31.1%), systemic corticosteroids (115 patients, 19.8%), antivirals (85 patients, 14.6%), and antibiotics (66 patients, 11.3%), mostly macrolides (45 patients, 7.7%). Long-term sequelae were rare (1.3%). Pediatric EM was reported in 19 infants (3.2%). The main trigger was vaccination (9 patients). Infantile EM was EM major in 2 cases and EM minor in 17. Infants were less prone to develop EM major than older children (P < .01). Pediatric EM was recurrent in 83 cases (14.3%), which was triggered by HSV in 36 patients (61%). Recurrence affected older children.

LIMITATIONS

Potential confusion between Steven Johnson syndrome and EM major in addition to publication bias.

CONCLUSION

Pediatric EM is a rare disease, mainly triggered by infections. This condition can affect all mucosal surfaces, most commonly the oral mucosae. The diagnosis is clinical, and management relies on supportive care. Vaccines are a particular trigger in infants. Recurrent cases are most commonly linked to HSV. Dermatologists and pediatricians should be aware of this potentially recurrent and severe condition.

Clinical and histologic features of Mycoplasma pneumoniae-related erythema multiforme: A single-center series of 33 cases compared with 100 cases induced by other causes

BACKGROUND

Mycoplasma pneumoniae infection has been documented in erythema multiforme (EM) and Stevens-Johnson syndrome-toxic epidermal necrosis (SJS-TEN). Clinical aspects of M pneumoniae-related EM have been poorly described in the literature.

OBJECTIVE

To highlight differences between M pneumoniae EM and non-M pneumoniae EM.

METHODS

This single-center, retrospective cohort study included all patients admitted to our dermatology department for EM during 2000-2015. We compared epidemiologic, clinical, and histologic data and follow-up for M pneumoniae EM and non-M pneumoniae EM cases.

RESULTS

Thirty-three patients with M pneumoniae EM were compared with 100 patients with non-M pneumoniae EM. Disease onset in winter was more frequent with M pneumoniae EM (P = .003). Acrally distributed lesions (32% vs 88%, P < .0001) and typical targets (45% vs 74%, P = .01) were less common in M pneumoniae EM than non-M pneumoniae EM. Multiple (≥2) mucousal membrane involvement was more frequent in M pneumoniae EM than non-M pneumoniae EM (97% vs 60%; P < .0001), as were mucosal and respiratory tract sequelae (P < .05). The mean hospital stay was longer with M pneumoniae EM patients: 9.5 days versus 5.1 days (P = .0002). A TEN-like pattern was observed in all 14 (100%) M pneumoniae EM skin biopsies versus 10 of 27 (48%) non-M pneumoniae EM biopsies (P < .001).

LIMITATIONS

The retrospective design.

CONCLUSION

M pneumoniae EM has a distinctive presentation compared with non-M pneumoniae EM, with more diffuse and atypical targets, more mucositis and respiratory tract sequelae. Histologic data show a TEN-like pattern in all M pneumoniae EM skin samples.

A retrospective review of hyperaesthetic leucotrichia in horses in the USA

BACKGROUND

Hyperaesthetic leucotrichia (HL) rarely affects horses and causes painful lesions on the dorsum that result in leucotrichia. This may be a variant of erythema multiforme (EM), but there are no studies investigating this condition.

OBJECTIVES

Describe the clinical and histological features of HL and compare them to the histological features of EM.

METHODS

A retrospective review of medical records from 1985 to 2015 identified 15 horses with HL. Thirteen biopsies of HL and five of EM were evaluated and compared.

RESULTS

Arabian horses and their crosses (χ(2) (1)  = 8.56, P < 0.01) and American paint horses (χ(2) (1)  = 6.64, P < 0.05) were over represented. The onset of clinical signs was between April and September (14 of 15). The most common clinical signs were pain (15 of 15), leucotrichia (11 of 15), crusting (10 of 15) and alopecia (8 of 15) limited to darkly pigmented skin. The lesions recurred seasonally in 6 of 12 horses and unpredictably in 1 of 12 horse. The most common histological features were the presence of large stellate cells (13 of 13) and oedema (12 of 13) in the superficial dermis, perivascular to diffuse lymphocytic inflammation (13 of 13), pigmentary incontinence (12 of 13), apoptotic keratinocytes (9 of 13) and vesicle formation (8 of 13). Horses with EM (n = 5) had significantly more acanthosis (z = -2.40, P < 0.02) and lymphocytic exocytosis (z = -3.1, P < 0.004), satellitosis (Fisher's exact P = 0.02) and inflammation (z = -2.91, P < 0.004). Horses with HL had significantly more pigmentary incontinence (z = 2.13, P < 0.04) and superficial dermal oedema (z = 2.56, P < 0.002).

CONCLUSIONS

HL affects primarily Arabian horses and American paint horses. It occurs mainly in summer and may recur. Histologically HL shares features with EM, but there are significant differences between them.

Efficacy of interferon in recurrent valaciclovir-refractory erythema multiforme in a patient not infected with hepatitis C virus

Recurrent erythema multiforme (EM) is rare and is most typically related to infections with herpes simplex virus. Prophylactic administration of valaciclovir is the first-line treatment, but there is no agreement about second-line treatment in cases of ineffectiveness. We present a 31-year-old man who was not infected with hepatitis C virus (HCV), and had a history of severe and recurrent EM, unresponsive to valaciclovir, colchicine and hydroxychloroquine. The patient noticed that an intermittent flu-like illness seemed to have abrogated an EM flare. Because of this observation, the next EM flares were treated with short courses of interferon, which gave rapid and complete efficacy. Efficacy of interferon in EM has only been reported in two previous patients, in whom the drug was administered to treat HCV infection. Efficiency was attributed to treatment of the underlying HCV infection, which was thought to be the origin of EM in both cases. This is the first case, to our knowledge, reporting a dramatic response to interferon-alfa in a patient who was not infected with HCV.

Rituximab, a new treatment for difficult-to-treat chronic erythema multiforme major? Five cases

BACKGROUND

Erythema multiforme major (EMM) is an inflammatory disease affecting skin and mucosae, often triggered by infection with Herpes simplex virus. Some patients have a chronic disease associated with antidesmoplakin autoantibodies, but the pathophysiology remains to be elucidated. First-line treatment is antiviral therapy. With treatment failure or in patients without herpes-triggered disease, thalidomide is effective but has neurological side-effects. Alternatives (dapsone, immunosuppressant agents) are not codified. For many patients, systemic steroids use is chronic. The immunosuppressant drug rituximab (RTX) may be effective.

OBJECTIVES

We report five cases of severe chronic EMM treated with rituximab (RTX).

METHODS

Five patients with severe chronic EMM for 9-20 years received RTX after failure or side-effects of several treatments, especially antiviral therapy and thalidomide. All had chronic use of steroids. Four patients had antidesmoplakin autoantibodies.

RESULTS

Four patients experienced complete or quasi-complete remission of EMM with withdrawal of steroids and one patient partial remission, for 3-11 months. Disease relapsed in all patients, and three received a second cycle of RTX with shorter duration of efficacy. Two patients received a third cycle, one without efficacy.

CONCLUSION

The use of RTX for many autoimmune diseases, especially pemphigus, is increasing. Chronic EMM, especially EMM associated to antidesmoplakin autoantibodies, is an inflammatory disease in which the role of B cells is not well understood. However, we report a favourable benefit of RTX treatment for months in five patients with severe disease. RTX could be a therapeutic option in severe, difficult-to-treat EMM.

Erythema Multiforme Associated with Respiratory Disease in a Commercial Breeding Pig Herd

This study describes an erythema multiforme (EM) in breeding sows, after their mixing in the group housing system. Sows at 30-35 days of gestation showed red and raised skin areas, depression, anorexia, fever, respiratory problems, and increased return to estrus. Blood and nasal samples from diseased sows were examined by quantitative polymerase chain reaction and enzyme-linked immunosorbent assay for respiratory pathogens. Hematological and biochemical analyses were performed on the blood samples. From diseased sows, vaginal swabs for microbiological examinations and samples at slaughterhouse for gross and microscopic examinations were collected. Samples from the complete gestation and lactation feed were examined for mycotoxins. All sampled sows were seropositive for Actinobacillus pleuropneumoniae (App) and porcine reproductive and respiratory syndrome virus (PRRSV). No viremia for PRRSV and porcine circovirus type 2 were detected. All nasal samples were positive for Streptococcus suis, one for Swine Influenza Virus and one for App, Hemophilus parasuis, and S. suis. In all vaginal swabs, Escherichia coli and Streptococcus spp. were detected. Diseased sows had moderate leukocytosis, mild anemia, and thrombocytopenia. No mycotoxins were detected in feed. Histopathological examination revealed increased vascularization of the superficial and middle dermis. EM was likely due to illness caused by viral and bacterial infections. This study suggests that stress caused by the sows' mixing might have triggered the problem.

Erythema multiforme, Stevens-Johnson syndrome and toxic epidermal necrolysis: a comparative review

BACKGROUND

Human erythema multiforme (EM) and Stevens-Johnson syndrome/toxic epidermal necrolysis (SJS/TEN) are separate conditions. There is no consensus on classification criteria for the eponymous diseases in animals.

RESULTS

Animal EM is very different from 90% of human EM, which is herpes virus associated (HAEM). Animals lack acrally distributed, typical raised targets. Unlike canine parvovirus 'EM', HAEM is not an active infection. Animal EM is often attributed to drugs, but this is rarely proved. Conversely, human and animal SJS/TEN are almost identical, life-threatening disorders of epidermal necrosis and detachment, typically triggered by drugs (occasionally by infectious agents). Both EM and SJS/TEN are mediated by cytotoxic lymphocyte responses against altered keratinocytes (infectious agents or drugs). Apoptosis results from direct cytotoxicity or through soluble mediators, namely Fas ligand, granzymes, perforin and granulysin. Diagnosis in humans is clinicopathological, with emphasis on clinical lesions; histopathology confirms the pathological process as interface (cytotoxic) dermatitis. Human EM is self-limiting; only recurrent and rare persistent cases require antiviral/immunosuppressive therapies. Drug-induced EM responds to drug withdrawal. Idiopathic canine EM (>40%) is usually chronic, refractory to treatment and may represent heterogeneous conditions. Early identification and removal of the causative drug and high-quality supportive care are critical in SJS/TEN. Mortality rate is nevertheless high.

CONCLUSIONS AND CLINICAL IMPORTANCE

(1) Histopathological lesions do not reliably differentiate EM, SJS and TEN. (2) A multicentre study to develop a consensus set of clinical criteria for EM and SJS/TEN in animals is overdue. (3) No adjunctive therapies, including intravenous immunoglobulin and ciclosporin, have met evidence-based standards.

Acute skin graft-versus-host disease with molecular features mimicking herpes simplex virus-associated erythema multiforme: report of three cases

BACKGROUND

Acute skin erythematous lesions that follow allogeneic hematopoietic stem cell transplantation (HSCT) and are histologically diagnosed as graft-versus-host disease (GVHD) are often associated with reactivation of latent herpes simplex virus (HSV).

OBJECTIVE

To further examine the relationship between reactivated HSV and GVHD development.

METHODS

We present 3 patients with acute skin GVHD after allogeneic HSCT who were studied prospectively for expression of the HSV antigen Pol, which is involved in HSV-associated erythema multiforme.

RESULTS

Pol was expressed in the GVHD lesions but not the pre-HSCT normal skin or peripheral blood mononuclear cells. Lesion severity correlated with the Pol levels but not the histopathologically defined GVHD grade. Lesion development was accompanied by increased numbers of Pol+ circulating/skin-infiltrating CD34+ stem cells and CD1a+ and other dermal dendritic cells.

CONCLUSIONS

Subclinical HSV infection of circulating CD34+ cells can contribute to some post-HSCT skin lesions histologically diagnosed as GVHD, with potential preventive and therapeutic implications.

Clinicopathologic analysis of coxsackievirus a6 new variant induced widespread mucocutaneous bullous reactions mimicking severe cutaneous adverse reactions

BACKGROUND

The cutaneous manifestations of human enterovirus (HEV) infection are usually limited, such as hand-foot-mouth disease. By comparison, Stevens-Johnson syndrome (SJS) is a life-threatening severe cutaneous adverse reaction (SCAR), mainly caused by drugs. During the HEV outbreaks in 2010-2012 in Taiwan, we identified 21 patients who developed widespread blistering mucocutaneous reactions without any suspected drug causality.

METHODS

We screened possible pathogen(s) for detecting human herpes virus (HHV1-HHV7), HEV, or Mycoplasma pneumoniae infections using throat swab virus cultures, real-time PCR, DNA sequencing, immunochemistry and electron microscopy analyses.

RESULTS

Coxsackievirus A6 (CVA6) DNA was identified in the blistering skin lesions in 6 of 21 patients. Cytotoxic T lymphocytes and natural killer cells expressing granulysin predominantly infiltrated into the skin lesions, sharing the histopathological features with SJS. Intact CVA6 viral particles were identified in the blister fluids and skin lesions by electron microscopy. The phylogenetic analysis of the viral genome showed the CVA6 DNA sequence sharing higher similarity (97.6%-98.1%) to CVA6 strains reported from Finland at 2008.

CONCLUSIONS

This study identifies a new variant of CVA6 as the causative agent for severe mucocutaneous blistering reactions mimicking SCAR. An awareness of this unusual presentation of HEV infection is needed in the epidemic area.

Herpes associated erythema multiforme

Erythema multiforme is an acute and a self-limiting mucocutaneous hypersensitivity reaction triggered by certain infections and medications. One of the most common predisposing factors for erythema multiforme is infection with herpes simplex virus. Herpes associated erythema multiforme (HAEM) is an acute exudative dermatic and mucosal disease caused by the infecting herpes simplex virus. It has recurrence and idiorestriction, characterized by increasing of CD4+T leukomonocyte. This article reports a case of HAEM in a 9-year-old girl, with a review of relevant literature, and discusses the pathophysiology and treatment of erythema multiforme triggered by herpes simplex virus

Erythema multiforme-oral variant: case report and review of literature

Erythema multiforme (EM) is an interesting dermatologic disease which has oral manifestations. EM is clinically characterized by a "minor" form and a "major" form. It presents a diagnostic dilemma because the oral cavity has the ability to produce varied manifestations. Infections (particularly herpes simplex and mycoplasma pneumonia) and drugs seem to predispose toward the development of EM. The range of possible etiologies for oral disease is immense. Therefore, an otolaryngologist or a dentist while treating such patients should have a differential diagnosis for all oral lesions. We report a case of erythema multiforme in which alcohol (ethanol) seems to be the precipitating factor and have also reviewed the English literature in the present context.

Recurrent erythema multiforme after alcohol ingestion in a patient receiving ciprofloxacin: a case report

The incidence of cutaneous adverse reactions to quinolones is low; moreover their development in patients with concomitant alcohol consumption is a phenomenon that has been scarcely reported. We present a case of 46-year-old male who developed erythema multiforme after ingestion of alcohol, while being treated with ciprofloxacin. The lesion was self-limiting and abstinence from alcohol permitted the completion of the course of therapy without any other adverse reaction.

Acute skin eruptions that are positive for herpes simplex virus DNA polymerase in patients with stem cell transplantation: a new manifestation within the erythema multiforme reactive dermatoses

BACKGROUND

Patients with stem cell transplantation (SCT) develop erythematous eruptions (SCTE) that are often misdiagnosed and poorly treated. Latent herpes simplex virus (HSV) is likely to be reactivated by SCT-associated immunosuppression. Therefore, one of the differential diagnostic possibilities for SCTE is HSV-associated erythema multiforme (HAEM) in which HSV genetic fragments localize in stem cells that deliver them to the skin on differentiation.

OBSERVATIONS

Lesional skin from patients with SCTE, HAEM, HSV, or drug-induced erythema (DIEM) was stained with antibodies to the HSV antigen DNA polymerase (Pol) and the major capsid protein, virion protein 5 (VP5). The HSV DNA polymerase Pol was expressed in 79% of patients with SCTE and 75% of those with HAEM. The protein VP5 was not expressed in these patients, indicative of the absence of virus replication. Findings in patients with DIEM were negative for both antigens, and those with HSV lesions were positive for both antigens.

CONCLUSIONS

There is a growing problem with SCTE, related to the increasing numbers of performed SCT. The greater frequency of SCT-generated circulating stem cells in patients with hematological malignant neoplasms (who have latent HSV infection) may result in a widespread SCTE characterized by skin deposition of HSV DNA fragments, notably those expressing Pol antigen. This HAEM-like presentation should be considered in the differential diagnosis of SCTE. Prolonged high-dosage antiviral chemotherapy during and after hospitalization may be warranted.

Interface dermatitis

Interface dermatitis can be classified based upon the cell type that dominates the infiltrate (ie, neutrophilic, lymphocytic, or lymphohistiocytic) or by the intensity of the interface inflammation. Regarding lymphocytic interface dermatitis, there are 2 broad categories: cell-poor interface dermatitis, when only a sparse infiltrate of inflammatory cells is present along the dermoepidermal junction, or cell rich, which typically occurs as a heavy bandlike infiltrate that obscures the basal layers of the epidermis. In the case of lymphocytic interface dermatitis, the latter is often termed a lichenoid interface dermatitis. This review focuses upon the mononuclear cell-predominant forms of interface dermatitis.

Oral mucosal diseases: Erythema multiforme

Erythema multiforme (EM) is a rare acute mucocutaneous condition caused by a hypersensitivity reaction with the appearance of cytotoxic T lymphocytes in the epithelium that induce apoptosis in keratinocytes, which leads to satellite cell necrosis. EM can be triggered by a range of factors, but the best documented association is with preceding infection with herpes simplex virus (HSV). Most other cases are initiated by drugs. EM has been classified into a number of variants, mainly minor and major forms, as it may involve the mouth alone, or present as a skin eruption with or without oral or other lesions of the mucous membrane. EM minor typically affects only one mucosa, and may be associated with symmetrical target skin lesions on the extremities. EM major typically involves two or more mucous membranes with more variable skin involvement. A severe variant of EM major is Stevens-Johnson syndrome, which typically extensively involves the skin. Both EM major and Stevens-Johnson syndrome can involve internal organs and produce systemic symptoms. Treatment of EM is controversial, as there is no reliable evidence. Precipitants should be avoided or treated and, in severe cases, corticosteroids may be needed. Toxic epidermal necrolysis may be similar to Stevens-Johnson syndrome, but many experts regard it as a discrete disease, and therefore it is not discussed here.

Ulcerative lesions of the mouth: an update for the general medical practitioner

Oral ulceration is a common complaint of patients attending out-patient clinics. Because of the diversity in causes of oral ulceration, patients presenting with oral mucosal disease can be challenging to diagnose and manage. Patients with signs or symptoms of oral ulcers are sometimes referred to gastroenterology clinics; however, in most instances the ulcers do not result from gastrointestinal disease. The aim of the present article is to review aspects of the etiology, diagnosis and management of common ulcerative disorders of the oral mucosa. A search in the National Library of Medicine computerized bibliographic database MEDLINE was performed. Selection of publications, extraction of data, and validity assessment were then performed by the authors. Based upon the searched literature, it is concluded that there are several systemic disorders that can present with similar clinical signs and symptoms, and knowledge of each disease is necessary for the clinician to provide proper management.

Human herpes simplex virus infections: epidemiology, pathogenesis, symptomatology, diagnosis, and management

Eight of the more than 80 known herpesviruses are human pathogens. Human herpes simplex virus (HSV) is a contagious infection with a large reservoir in the general population. It has a potential for significant complications in the immunocompromised host. In addition, psychological distress caused by the negative stigma associated with genital herpes and visible facial lesions in those experiencing frequent outbreaks renders it a challenging clinical dilemma. This article reviews the epidemiology, pathogenesis, and diagnostic features of HSV infections, providing the clinician with an up-to-date understanding of the available management strategies for mucocutaneous HSV-induced disease.

The Herpes simplex virus gene Pol expressed in herpes-associated erythema multiforme lesions upregulates/activates SP1 and inflammatory cytokines

BACKGROUND/AIMS

Herpes-simplex-virus-associated erythema multiforme (HAEM) is characterized by lesional skin expression of the viral protein Pol and localized inflammation. The objective of this study is to examine the mechanism whereby Pol induces localized inflammation.

METHODS

A431 cells transfected with Pol or an empty vector and lesional skin from HAEM or drug-induced erythema multiforme patients were examined for expression of the transcription factor SP1 and SP1-regulated genes by immunoblotting, immunohistochemistry and immunofluorescence.

RESULTS

SP1, TGF-beta, p21(waf1) and Hsp27 were upregulated in A431 cells transfected with Pol but not the empty vector. Expression was further increased by exposure to IFN-gamma. Pol+ HAEM lesional skin expressed SP1, Hsp27, TGF-beta and p21(waf1). Normal skin and drug-induced erythema multiforme lesional skin were negative.

CONCLUSION

The data indicate that Pol activates SP1, causing upregulation of SP1 target genes (notably TGF-beta) involved in localized inflammation. Upregulation is potentiated by IFN-gamma.

Erythema multiforme and related disorders

Erythema multiforme (EM) and related disorders comprise a group of mucocutaneous disorders characterized by variable degrees of mucosal and cutaneous blistering and ulceration that occasionally can give rise to systemic upset and possibly compromise life. The clinical classification of these disorders has often been variable, thus making definitive diagnosis sometimes difficult. Despite being often caused by, or at least associated with, infection or drug therapy, the pathogenic mechanisms of these disorders remain unclear, and as a consequence, there are no evidence-based, reliably effective therapies. The present article reviews aspects of EM and related disorders of relevance to oral medicine clinical practice and highlights the associated potential etiologic agents, pathogenic mechanisms and therapies.

Expression of cytokines and chemokine receptors in the cutaneous lesions of erythema multiforme and Stevens-Johnson syndrome/toxic epidermal necrolysis

BACKGROUND

Erythema multiforme (EM) and Stevens-Johnson syndrome/toxic epidermal necrolysis (SJS/TEN) are caused by a dysregulation of cellular immunity.

OBJECTIVES

To evaluate further the potential role of certain cytokines and chemokine receptors in cutaneous lesions of patients affected by EM and SJS/TEN and to establish whether such diseases are polarized preferentially towards a T-helper (Th) 1 or Th2 pattern.

METHODS

Biopsy specimens from eight patients with EM, six with SJS/TEN and three healthy controls were stained for immunohistochemical examination using the alkaline phosphatase-antialkaline phosphatase method. The monoclonal antibodies used included those to tumour necrosis factor (TNF)-alpha, interferon (IFN)-gamma, interleukin (IL)-2, IL-5, IL-13, receptor 3 for C-C chemokines (CCR3), receptor 3 for C-x-C chemokines (CXCR3) and CXCR4.

RESULTS

The SJS/TEN specimens showed significantly higher expression of all the cytokines and chemokine receptors (except CXCR3) tested than the EM specimens. Both lesional series showed significantly higher expression of all the receptors tested than the healthy control specimens, with the sole exception of a lower expression of CCR3 in EM specimens. Comparison between molecules associated with a Th1 or Th2 response revealed a predominance of Th1 response in EM and no significant imbalance between Th1 and Th2 in SJS/TEN.

CONCLUSIONS

We have provided further evidence that TNF-alpha is strongly expressed in SJS/TEN lesions and therefore it may be involved in the epidermal necrosis featured in such diseases. IFN-gamma may play an important role both in EM and SJS/TEN. IL-2, IL-5 and IL-13 may contribute to the cutaneous immunoinflammation in these diseases. Chemokine receptors may be involved strongly in the recruitment of inflammatory cells in lesional skin. In our cases we found a sharp polarization towards a Th1 pattern in EM, while the SJS/TEN lesions showed a mixed Th1/Th2 pattern.

The CD40/CD40 ligand system is expressed in the cutaneous lesions of erythema multiforme and Stevens-Johnson syndrome/toxic epidermal necrolysis spectrum

BACKGROUND

Erythema multiforme (EM) and Stevens-Johnson syndrome (SJS)/toxic epidermal necrolysis (TEN) are determined by a dysregulation of cellular immunity.

OBJECTIVES

To evaluate the effector role of cellular immunity and the involvement of the CD40/CD40 ligand (CD40L) system in the pathogenesis of EM and SJS/TEN.

METHODS

Biopsy specimens from eight patients with EM and six with SJS/TEN were stained for immunohistochemical examination using the alkaline phosphatase/antialkaline phosphatase method. The monoclonal antibodies used included those to CD1a, CD4, CD8, CD40, CD40L, CD68, Fas, Fas ligand (FasL) and myeloperoxidase.

RESULTS

The cellular infiltrate in both EM and SJS/TEN lesions was composed mainly of T lymphocytes and CD68+ macrophages. We also detected large amounts of neutrophils. Fas and FasL were very highly expressed in SJS and TEN, but weakly in EM. CD40 staining was strong in all tissue sections; there were numerous CD40L+ cells in SJS/TEN but much fewer in EM.

CONCLUSIONS

Activated T lymphocytes and macrophages, but also neutrophils, are presumably the main triggers of mucocutaneous damage in the SJS/TEN disease spectrum. The Fas/FasL system is significantly expressed in SJS/TEN lesions, but not in EM, where this apoptotic pathway presumably does not play a pivotal role in the epidermal damage. We suggest that the CD40/CD40L system may represent an important pathway of induction of SJS/TEN lesions, while in EM it would contribute to the immunoinflammation only as a second-line mechanism.

Number IV Erythema multiforme

Erythema multiforme (EM) is an acute mucocutaneous hypersensitivity reaction characterised by a skin eruption, with or without oral or other mucous membrane lesions. Occasionally EM may involve the mouth alone. EM has been classified into a number of different variants based on the degree of mucosal involvement and the nature and distribution of the skin lesions. EM minor typically affects no more than one mucosa, is the most common form and may be associated with symmetrical target lesions on the extremities. EM major is more severe, typically involving two or more mucous membranes with more variable skin involvement - which is used to distinguish it from Stevens-Johnson syndrome (SJS), where there is extensive skin involvement and significant morbidity and a mortality rate of 5-15%. Both EM major and SJS can involve internal organs and typically are associated with systemic symptoms. Toxic epidermal necrolysis (TEN) may be a severe manifestation of EM, but some experts regard it as a discrete disease. EM can be triggered by a number of factors, but the best documented is preceding infection with herpes simplex virus (HSV), the lesions resulting from a cell mediated immune reaction triggered by HSV-DNA. SJS and TEN are usually initiated by drugs, and the tissue damage is mediated by soluble factors including Fas and FasL.

CD34+ cells in the peripheral blood transport herpes simplex virus DNA fragments to the skin of patients with erythema multiforme (HAEM)

Herpes simplex virus (HSV)-associated erythema multiforme (HAEM) is a recurrent disease characterized by the presence and expression of HSV DNA fragments in lesional skin. Our studies examined the mechanism of viral DNA transport to the skin of HAEM patients. CD34+ cells were isolated from the blood of normal subjects and HSV and HAEM patients during acute lesions and at quiescence. They were cultured with cytokines that favor their differentiation into Langerhans cells (LC) precursors (CD1a+/CD14-) and examined for HSV replication, HSV-induced cellular alterations, viral DNA fragmentation, and clearance. CD34+ cells from all study groups were non-permissive for HSV replication but infection favored their differentiation into CD1a+/CD14- LC precursors and upregulated E-cadherin expression, thereby assisting LC targeting to the skin. Only HAEM patients had CD34+ cells that retained viral DNA fragments, notably polymerase DNA, for at least 7 d of in vitro culture. The percentages of circulating CD34+ (and CD34+/CLA+) cells were significantly higher in HAEM patients at the time of acute lesions. A similar increase was not seen for HSV patients. The data are the first report implicating CD34+ cells in HAEM pathogenesis, likely by transporting HSV DNA fragments to lesional skin.

Review article: oral ulcers and its relevance to systemic disorders

Oral ulceration is a common problem, and is sometimes a marker of gastroenterological disease. Patients with signs or symptoms of oral ulcers are sometimes referred to gastroenterology clinics, however, in most instances the ulcers does not reflect gastrointestinal disease. Indeed, a spectrum of disorders other than those of the gut can give rise to oral mucosal ulcers ranging from minor local trauma to significant local disease such as malignancy or systemic illness. This present article reviews aspects of the aetiology, diagnosis and management of common ulcerative disorders of the oral mucosa.

Detection and genotyping of human herpes simplex viruses in cutaneous lesions of erythema multiforme by nested PCR

A subset of erythema multiforme (erythema multiforme) is associated with herpes simplex virus (HSV) infection; viral cultures of erythema multiforme lesions are, however, usually negative and viral antigens difficult to identify. Polymerase chain reaction (PCR) has been used to demonstrate the association, hence, is currently the only available sensitive diagnostic means for HSV-associated erythema multiforme. A nested PCR, which could simultaneously detect and genotype HSV in erythema multiforme lesions and in clinical swab specimen was developed using the DNA polymerase gene of HSV as target gene because it is the only detectable HSV gene in a high proportion of erythema multiforme lesions. The PCR has demonstrated its robust sensitivity on swab samples by being able to detect further 45.3% HSV cases in comparison with virus isolation with 100% specificity in both detection and genotyping confirmed by virus isolation and DNA sequencing. This study represents the first investigation of typing HSV virus in HSV-associated erythema multiforme patients, and the finding that 66.7% of the patients was attributed to HSV1, 27.8% to HSV2, and 5.6% to HSV1 and 2 co-infection may reflect the distribution of HSV1 and 2 in local general population.

Recent progress in herpes simplex virus immunobiology and vaccine research

Herpes simplex virus types 1 and 2 (HSV-1 and HSV-2) cause prevalent, chronic infections that have serious outcomes in some individuals. Neonatal herpes may occur when the infant traverses the cervix during maternal genital herpes. Genital herpes is a major risk factor for human immunodeficiency virus type 1 transmission. Considerable efforts have been made to design and test vaccines for HSV, focusing on genital infection with HSV-2. Several protein subunit vaccines based on HSV-2 envelope glycoproteins have reached advanced-phase clinical trials. These antigens were chosen because they are the targets of neutralizing-antibody responses and because they elicit cellular immunity. Encouraging results have been reported in studies of treatment of HSV-seronegative women with a vaccine consisting of truncated glycoprotein D of HSV-2 and a novel adjuvant. Because most sexual HSV transmission occurs during asymptomatic shedding, it is important to evaluate the impact of vaccination on HSV-2 infection, clinically apparent genital herpes, and HSV shedding among vaccine recipients who acquire infection. There are several other attractive formats, including subunit vaccines that target cellular immune responses, live attenuated virus strains, and mutant strains that undergo incomplete lytic replication. HSV vaccines have also been evaluated for the immunotherapy of established HSV infection.

Interaction of HSV-1 infected peripheral blood mononuclear cells with cultured dermal microvascular endothelial cells: a potential model for the pathogenesis of HSV-1 induced erythema multiforme

The effect of herpes virus infection on human dermal microvascular endothelial cells and herpes-virus-1-infected peripheral blood mononuclear cells on human dermal microvascular endothelial cells was studied as a model of herpes-associated erythema multiforme. After infection of human dermal microvascular endothelial cells with native herpes virus and overnight culture, 60%--90% of human dermal microvascular endothelial cells showed cytopathic effects. HLA class I molecules and CD31 (PECAM-1) surface expression in herpes-virus-infected endothelial cells were substantially downregulated, whereas CD54 (ICAM-1) remained unchanged. Cocultivation with herpes-virus-1-infected peripheral blood mononuclear cells left characteristic plaques on the human dermal microvascular endothelial cell monolayer; however, very few human dermal microvascular endothelial cells (1%--3%) were infected. Adhesion molecule expression of human dermal microvascular endothelial cells cocultivated with herpes-virus-infected peripheral blood mononuclear cells demonstrated a 5-fold increase in CD54 expression, a 2-fold increase in HLA class I expression, but no change of CD31 by fluorescence-activated cell sorter analysis. Incubation of human dermal microvascular endothelial cells with ultraviolet-C irradiated herpes-virus-infected peripheral blood mononuclear cells had no effect on morphology or adhesion molecule expression levels. Changes of adhesion molecule expression by direct infection or cocultivation with peripheral blood mononuclear cells (with native and ultraviolet-C inactivated herpes virus infection) were also documented at the mRNA level. Adhesion assays demonstrated an increased binding of herpes-virus-infected peripheral blood mononuclear cells versus noninfected peripheral blood mononuclear cells to noninfected human dermal microvascular endothelial cells. Our results suggest that incubation of herpes-virus-infected peripheral blood mononuclear cells with human dermal microvascular endothelial cells induces significant upregulation of CD54 and major histocompatibility complex class I molecules in the surrounding noninfected human dermal microvascular endothelial cells, which is associated with an increased binding of peripheral blood mononuclear cells. Our in vitro findings may serve as a model for herpes-associated erythema multiforme possibly explaining the dermal inflammatory reaction seen in that condition.

Toxinological and immunological studies of capillary electrophoresis fractionated Chrysaora quinquecirrha (Desor) fishing tentacle and Chironex fleckeri Southcott nematocyst venoms

Repeated runs of capillary electrophoresis (CE) were used to study partially-purified jellyfish nematocyst venom protein in concentrations sufficient to perform toxinological assays. Nematocyst venoms from Chironex fleckeri (Cf) and Chysaora quinquecirrha were processed. The CE eluate was divided into quadrants by scanning protein content. The fourth fraction of both jellyfish venoms, contained proteins with the smallest molecular weight components, which were responsible for the highest hemolysins and the humoral and cell-mediated immunological activity. Cytotoxic Cf lethal factor activity against human liver cells was widely dispersed throughout both venoms but more prominent in fraction 4. A V(beta) receptor human T-cell repertoire was not species-specific for either crude or fractionated jellyfish nematocyst venom.

Parvovirus infection of keratinocytes as a cause of canine erythema multiforme

Erythema multiforme major was diagnosed in a dog with necrotizing parvoviral enteritis. Skin lesions consisted of ulceration of the footpads, pressure points, mouth, and vaginal mucosa; vesicles in the oral cavity; and erythematous patches on the abdomen and perivulvar skin. Microscopic examination of mucosal and haired skin specimens revealed lymphocyte-associated keratinocyte apoptosis at various levels of the epidermis. Basophilic cytoplasmic inclusions were seen in basal and suprabasal keratinocytes. Immunohistochemical staining, performed with canine parvovirus-2-specific monoclonal antibodies, confirmed the parvovirus nature of the inclusions in the nucleus and cytoplasm of oral and skin epithelial cells. This is the first case of canine erythema multiforme reported to be caused by a viral infection of keratinocytes. This case study indicates that the search for epitheliotropic viruses should be attempted in cases of erythema multiforme in which a drug cause cannot be identified.

A novel human gene similar to the protein kinase (PK) coding domain of the large subunit of herpes simplex virus type 2 ribonucleotide reductase (ICP10) codes for a serine-threonine PK and is expressed in melanoma cells

The large subunit of herpes simplex virus type 2 ribonucleotide reductase (ICP10) is a multifunctional protein that contains a serine-threonine protein kinase (PK) activity (Nelson, J. W., Zhu, J. , Smith, C. C., Kulka, M., and Aurelian, L. (1996) J. Biol. Chem. 271, 17021-17027). Phylogenetic analyses indicated that ICP10 PK belongs to a distinct subfamily of growth factor receptor serine-threonine PKs that are characterized by their ability to function with a limited number of conserved catalytic motifs (Hunter, J. C. R., Smith, C. C., and Aurelian, L. (1995) Int. J. Onc. 7, 515-522). Here, we report the isolation and characterization of a novel gene, designated H11, that contains an open reading frame of 588 nucleotides, which encodes a protein similar to ICP10 PK. The H11 protein has Mn(2+)-dependent serine-threonine-specific PK activity as determined with a GST-H11 fusion protein and by immununocomplex PK/immunoblotting assays of 293 cells transfected with a H11 eukaryotic expression vector. PK activity is ablated by mutation of Lys(113) within the presumtive catalytic motif II (invariant Lys). 293 cells stably transfected with H11 acquire anchorage-independent growth. Endogenous H11 RNA and the H11 phosphoprotein are expressed in melanoma cell lines and primary melanoma tissues at levels higher than in normal melanocytes and in benign nevi. Melanoma cell proliferation is inhibited by treatment with antisense oligonucleotides that inhibit H11 translation, suggesting that H11 expression is associated with cell growth.

Herpes simplex virus associated erythema multiforme (HAEM) is mechanistically distinct from drug-induced erythema multiforme: interferon-gamma is expressed in HAEM lesions and tumor necrosis factor-alpha in drug-induced erythema multiforme lesions

Erythema multiforme follows administration of several drugs or infection with various agents, including herpes simplex virus, a syndrome designated herpes simplex virus associated erythema multiforme. Lesional skin from 21 of 26 (81%) herpes simplex virus associated erythema multiforme patients was positive for herpes simplex virus gene expression as evidenced by reverse transcriptase-polymerase chain reaction with primers for DNA polymerase and/or immunohistochemistry with DNA polymerase antibody. Reverse transcriptase-polymerase chain reaction and immunohistochemistry studies indicated that herpes simplex virus associated erythema multiforme lesional skin from 16 of 21 (76%) DNA polymerase positive herpes simplex virus associated erythema multiforme patients was also positive for interferon-gamma, a product of T cells involved in delayed-type hypersensitivity (p < 0. 0001 by Pearson correlation coefficient). Interferon-gamma signals were in infiltrating mononuclear cells and in intercellular spaces within inflammatory sites in the epidermis and at the epidermis/dermis junction. Herpes simplex virus lesional skin was also positive for DNA polymerase [five of five (100%)] and interferon-gamma [four of five (80%)], but lesional skin from drug-induced erythema multiforme patients was negative. Lesional herpes simplex virus associated erythema multiforme keratinocytes also stained with antibody to transforming growth factor-beta [14 of 23 (61%)] and cyclin-dependent kinase inhibitor waf [12 of 18 (67%)]. Staining was also seen in keratinocytes from herpes simplex virus lesions [five of five (100%)], but not in normal skin. By contrast, staining with antibody to tumor necrosis factor-alpha, another pro-inflammatory cytokine, was seen in seven of 11 (64%) drug-induced erythema multiforme patients, but not in herpes simplex virus or herpes simplex virus associated erythema multiforme patients, and lesional keratinocytes from drug-induced erythema multiforme patients were negative for transforming growth factor-beta and cyclin-dependent kinase inhibitor waf. We interpret the data to indicate that herpes simplex virus associated erythema multiforme pathology includes a delayed-type hypersensitivity component and is mechanistically distinct from drug-induced erythema multiforme.