Ganglioside modulates ligand binding to the epidermal growth factor receptor

Whereas previous investigations have shown that pharmacologic addition of gangliosides inhibits keratinocyte proliferation by downregulating epidermal growth factor receptor phosphorylation, the underlying biochemical basis and physiologic relevance are unknown. Using Scatchard and displacement plots, we have shown that supplemental purified gangliosides decrease the binding of (125)I-labeled epidermal growth factor to keratinocyte-derived SCC12 cells. Conversely, SCC12 cells transfected with sialidase and thus depleted of gangliosides show increased ligand binding to the epidermal growth factor receptor, which is consistent with their increased proliferation in response to epidermal growth factor and transforming growth factor-alpha, and increased phosphorylation of the epidermal growth factor receptor, and downstream signal transduction pathway components. The mechanism of the altered binding appears to involve primarily decreased numbers of available receptors within the intact membrane, but not altered receptor protein expression. These studies provide evidence that the effect of gangliosides on keratinocyte proliferation results, at least in part, from the direct binding of ganglioside to the receptor and disruption of the receptor-ligand interaction. Manipulation of membrane ganglioside content may be a powerful new means to alter epidermal growth factor receptor-dependent cell proliferation.

Responses to anti-angiogenic therapies

Vascular tumors occur in approximately 10% of infants, and range from small cherry-red lesions to large, life-threatening tumors. Although the majority of these tumors involute after several years, there are few therapeutic options and their use is limited by the risk of side-effects. The recent increase in understanding of angiogenesis has led to investigations of new antiangiogenic treatment options using models of vascular tumors in mice. These studies have demonstrated the success of a variety of antiangiogenic approaches, including systemic administration of the antiangiogenic proteins AGM-1470 and angiostatin or of the matrix metalloproteinase inhibitor batimastat, and gene gun therapy with interleukin-12. Although these trials provide further evidence of the role of angiogenesis in the enlargement of these vascular tumors, their potential utility and safety await future trials in patients.

Dermatologic clues to inherited disease

Genetic diseases often have cutaneous manifestations, which can be the first or most prominent signs of the underlying problem. Recognition of these dermatologic clues allows prompt diagnosis and intervention. In this article, the authors have attempted to outline several important examples of genodermatoses.

Itraconazole pulse therapy for dermatophyte onychomycosis in children

BACKGROUND

Onychomycosis, or fungal infection of the nail, can occur in prepubertal children. However, its diagnosis is often missed or the condition is inappropriately treated with topical medication. Griseofulvin has been the therapy of choice, but even long-term treatment is associated with a poor cure rate and high rate of relapse. Trials with adult patients have shown that itraconazole pulse therapy for onychomycosis requires a shorter duration of total therapy than griseofulvin treatment and is rarely associated with adverse reactions, suggesting that it may be the treatment of choice for pediatric patients with onychomycosis.

DESIGN

We retrospectively reviewed the courses of prepubertal patients with dermatophyte onychomycosis who initiated treatment with itraconazole pulse therapy between January 1995 and June 1998.

SETTING

Urban and suburban pediatric dermatology clinics of a children's hospital.

PATIENTS

Seventeen prepubertal patients met the enrollment and follow-up criteria. These included fungal infection of the nail(s), documented by fungal culture and/or positive potassium hydroxide mounts of nail scrapings; at least 1 follow-up visit; and contact by telephone or clinic visit within 2 months prior to compilation of data. In 59% of patients, a relative living at the home had onychomycosis at the time of diagnosis.

INTERVENTION

Patients were treated with daily to twice-daily pulses of itraconazole, administered for 1 week of each of 3 to 5 months.

MAIN OUTCOME MEASURES

Clinical cure after itraconazole therapy in patients with documented onychomycosis and clinical and mycologic relapse after initial cure. Fungal cultures were not repeated if clinical cure was noted.

RESULTS

All but 1 patient responded fully to therapy, showing improvement within a few months and subsequently clearance (94% clinical cure rate). No patients experienced any clinical adverse reactions. No relapses occurred after clinical cure during a follow-up period of 1 to 4.25 years after initiation of therapy.

CONCLUSIONS

Itraconazole pulse therapy is effective and safe for the treatment of onychomycosis in children. The relapse rate in pediatric patients is lower than in adults, although the high frequency of onychomycosis in non-pediatric family members suggests that the recurrence risk is increased if other family members are not treated concomitantly.

Squaric acid immunotherapy for warts in children

BACKGROUND

Warts are a common pediatric skin infection caused by human papillomavirus (HPV). Spontaneous clearance of warts involves anti-HPV immunity, which may be enhanced by contact sensitizers. Squaric acid dibutylester (SADBE) is a nonmutagenic sensitizing agent useful for immunotherapy of alopecia areata.

OBJECTIVE

We hypothesized that SADBE home application might be effective therapy for warts.

METHODS

An open-label, retrospective study of 61 children with warts was performed. Sensitization with 2% SADBE on the forearm was followed with home application of 0.2% SADBE to warts 3 to 7 nights per week for at least 3 months.

RESULTS

Complete clearing occurred in 34 patients (58%), with a mean duration of therapy of 7 weeks. Partial clearing occurred in 11 (18%), and no response in 14 (24%). Clearance correlated with plantar distribution, wart duration under 2 years (P <.05), and first-line therapy with SADBE. Mild side effects occurred in one third of patients, were limited most commonly to mild erythema at the site of sensitization, and necessitated discontinuation of therapy in only 2 patients.

CONCLUSION

SADBE topical immunotherapy is a safe, effective option for home therapy of warts in children.

A new tissue adhesive for laceration repair in children

Bruns TB, Robinson BS Smith RJ, Kile DL, Davis TP, Sullivan KM, et al. J Pediatr 1998;132:1067-70.

Bullous systemic lupus erythematosus with autoantibodies recognizing multiple skin basement membrane components, bullous pemphigoid antigen 1, laminin-5, laminin-6, and type VII collagen

BACKGROUND

Bullous systemic lupus erythematosus is a generalized subepidermal blistering skin eruption in patients suffering from systemic lupus erythematosus. Type VII collagen was initially identified as the target antigen.

OBSERVATION

We studied an unusual patient who had bullous systemic lupus crythematosus. The patient fulfilled the criteria of systemic lupus with an antinuclear antibody titer of 1:5120. Immunopathological testing revealed in vivo deposition of all IgG subclasses, secretory IgA1, and both light chains at the patient's skin basement membrane. The in vivo-bound IgG and IgA were localized at the hemidesmosomes and lamina densa. The patient's IgG and IgA circulating autoantibodies labeled both the epidermal roof and the dermal floor of salt-split skin and recognized the hemidesmosomal protein BP230 as well as the full-length native form and the recombinant noncollagenous domain 1 of type VII collagen (anchoring fibril). In addition, the patient's IgG autoantibodies recognized the anchoring filament proteins laminin-5 and laminin-6 (alpha3 chain and gamma2 chain).

CONCLUSIONS

We conclude that patients with bullous systemic lupus erythematosus may have autoantibodies to multiple basement membrane components critical for epidermal-dermal junctional adhesion. Possible pathogenic mechanisms in this patient's clinical diseases include provocation of organ-specific disease (bullous disease) by systemic autoimmunity (lupus) and the "epitope spreading" immune phenomenon.

In vivo gene therapy with interleukin-12 inhibits primary vascular tumor growth and induces apoptosis in a mouse model

Interleukin-12 is proposed to have anti-neoplastic activity on the basis of both its anti-angiogenic and immunologic effects. Gene gun therapy with interleukin-12 cDNA into the peritumoral area of immunocompetent 129/J mice with life-threatening primary vascular tumors reduced tumor volume 7.5-fold and almost tripled the duration of mouse survival, in contrast with luciferase-bombarded control mice. Epidermal expression of mouse interleukin-12 elevated tumoral and serum levels of interferon-gamma and tumor necrosis factor-alpha, increased the tumoral populations of T lymphocyte and natural killer cells, and induced tumor apoptosis. Gene transfer of interleukin-12 had little effect on tumor volumes and survival of tumor-bearing athymic nude mice, emphasizing the requirement for T cell directed cellular immunity. Peritumoral gene gun introduction of interleukin-12 may be a novel, cost-effective approach to limit the growth and associated mortality of life-threatening tumors.

Ultrapotent topical corticosteroid treatment of childhood genital lichen sclerosus

OBJECTIVE

To observe the clinical effects of short-term application of ultrapotent topical corticosteroid on symptomatic genital lesions of lichen sclerosus in pediatric patients.

DESIGN

Case series of 10 prepubertal girls with genital lichen sclerosus. Ultrapotent topical corticosteroids were applied twice daily for 6 to 8 weeks and patients were reexamined at completion of treatment. Long-term follow-up over 6 months to 3 years.

SETTING

Pediatric dermatology clinic (referral center).

PATIENTS

Ten prepubertal girls with typical clinical features of genital and/or perianal lichen sclerosus.

INTERVENTION

Topical ultrapotent corticosteroid ointment was applied sparingly to affected areas for 6 to 8 weeks.

MAIN OUTCOME MEASURE

Improvement of erythema, whitening erosions, and atrophy. Subjective improvement of symptoms.

RESULTS

All patients showed partial or total subsistence of signs and symptoms of lichen sclerosus. Frequency and severity of recurrences varied, but patients responded within a few days to reapplication of ultrapotent topical corticosteroid. No significant adverse effects were noted after the initial 6- to 8-week course of therapy or during the 6-month to 3-year follow-up period.

CONCLUSION

A 6- to 8-week course of ultrapotent topical corticosteroid is a safe and effective treatment for genital lichen sclerosus in pediatric patients.

Hedgehog hives

BACKGROUND

Hedgehogs are increasingly popular pets in the United States and Europe. A number of infections may be acquired from these animals, and hedgehogs are possible hosts of parasites. However, to our knowledge there arc no previous reports of urticarial reactions to hedgehogs.

OBSERVATIONS

We describe 3 patients who developed an acute, transient, urticarial reaction after contact with the extended spines of pet hedgehogs. One patient also developed a more prolonged reaction at the site of contact. Interestingly, all 3 patients had documented allergies to cats and/or dogs. The results of prick testing in 1 patient to an extract of hedgehog dander produced an immediate wheal-and-flare reaction.

CONCLUSIONS

A variety of dermatologic disorders may be seen in handlers of hedgehogs. Due to the increasing popularity of these animals as pets, it is likely that these reactions will be noted more frequently by dermatologists. The presence of allergies to other pets may be predictive of hedgehog hives and further investigation of the cross reaction of various animal antigens may clarify this relationship.

Restoration of open reading frame resulting from skipping of an exon with an internal deletion in the COL7A1 gene

Restoration of open reading frame resulting from exon skipping has been documented as a mechanism of rescuing an mRNA transcript containing mutations. In this study, we describe a mutation in a family with dystrophic epidermolysis bullosa consisting of a 16-bp deletion within exon 87 of the type VII collagen gene (COL7A1) and predicted to lead to a frameshift and downstream premature termination codon. Unexpectedly, mRNA analysis revealed instead that the intraexonic deletion led to skipping of exon 87 and subsequent restoration of the open reading frame. The phenotypes and patterns of inheritance observed in this family arise from three different mutations, all of which affect RNA processing. Restoration of open reading frame by exon skipping represents a previously undescribed mechanism of action of intraexonic deletion mutations.

Keratin 17 mutations cause either steatocystoma multiplex or pachyonychia congenita type 2

Pachyonychia congenita type 2 (PC-2; Jackson-Lawler syndrome) is an autosomal dominant disorder characterized by hypertrophic nail dystrophy, mild focal keratoderma, multiple pilosebaceous cysts and other features of ectodermal dysplasia. Keratin 17 (K17) is a differentiation-specific keratin expressed in the nail bed, hair follicle, sebaceous gland and other epidermal appendages. Previously, we have demonstrated that PC-2 is caused by mutations in K17 and that similar mutations in this gene can present as steatocystoma multiplex with little or no nail dystrophy. Here, we describe three unrelated kindreds carrying K17 mutations. Two of these families have identical missense mutations (R94C) in the 1A domain of K17. However, while affected members of one kindred have the classical features of PC-2, affected persons in the other family have the steatocystoma multiplex phenotype. In a third family with PC-2, mutation N92S was detected, bringing the total number of distinct mutations reported in K17 thus far to 11. These results demonstrate that K17 mutations commonly underlie both PC-2 and steatocystoma multiplex and that the alternate phenotypes which arise from these genetic lesions in K17 are independent of the specific mutation involved.

Infantile acropustulosis revisited: history of scabies and response to topical corticosteroids

Infantile acropustulosis (IA) is a condition of young children characterized by recurrent episodes of pruritic vesicles and pustules in an acral distribution. Several reports describe patients with scabies infestation prior to the diagnosis of IA, although the relationship between the two remains unclear. Furthermore, optimal therapy is controversial. We reviewed the history of scabies and response to therapy in 21 patients diagnosed with IA at two institutions between 1983 and 1997. A history of prior treatment for scabies was noted in 14 patients, although only two had mites, feces, or ova detected on microscopic examination for diagnostic verification. All patients were treated with topical corticosteroids (4 with class I, 12 with class II, 3 with class III, 1 with class IV, and 1 with class VI). All 18 patients who returned for follow-up experienced significant improvement or cleared completely with treatment. There were no observed cutaneous or systemic side effects from corticosteroid therapy. We conclude that a history of preceding scabies is common in patients with IA, but often this diagnosis is made without microscopic confirmation. We also demonstrate that mid- to high-potency topical corticosteroids are a safe and effective first-line therapy for patients with IA.

Topical calcipotriene for morphea/linear scleroderma

BACKGROUND

Morphea and linear scleroderma are characterized by erythema, induration, telangiectasia, and dyspigmentation. There is no universally effective treatment. Oral calcitriol has been beneficial in the treatment of localized and extensive morphea/scleroderma, but the use of topical calcipotriene has not been reported.

OBJECTIVE

The purpose of this study was to evaluate the efficacy and safety of topical calcipotriene 0.005% ointment in the treatment of localized scleroderma.

METHODS

In a 3-month open-label study, 12 patients aged 12 to 38 years with biopsy-documented active morphea or linear scleroderma applied calcipotriene ointment under occlusion twice daily to plaques for 3 months. The condition of each patient had previously failed to respond to potent topical corticosteroids and, for some patients, systemic medications. Efficacy was assessed at baseline, 1 month, and 3 months. Levels of serum ionized calcium, intact parathyroid hormone, and 1,25-dihydroxyvitamin D and of random urinary calcium excretion were measured.

RESULTS

During the 3-month trial, the condition of all 12 patients showed statistically significant improvement in all studied features. No adverse effects were reported or detected through laboratory monitoring of mineral metabolism.

CONCLUSION

Topical calcipotriene 0.005% ointment may be an effective treatment for localized scleroderma, but double-blind placebo controlled studies are needed for confirmation.

LAMB3 mutations in generalized atrophic benign epidermolysis bullosa: consequences at the mRNA and protein levels

Generalized atrophic benign epidermolysis bullosa (GABEB; OMIM no. 226650) is a rare hemidesmosomal variant of EB, inherited in an autosomal recessive fashion. In previous studies, mutations in the gene (COL17A1) encoding the type XVII collagen, a transmembrane component of hemidesmosomes, were detected in most patients with GABEB. However, evidence for genetic defects in the laminin 5 genes has also been presented. In the present investigation, we examined three patients, representing two families with GABEB, for mutations in the LAMB3 gene. Heteroduplex scanning of the gene, followed by direct automated sequencing, revealed that Patient 1 was a compound heterozygote for a missense mutation (C293S) and a premature termination codon-causing mutation (1367delAC). The latter mutation resulted in accelerated mRNA decay, which rendered the corresponding mRNA transcript undetectable by reverse transcriptase-PCR. Patients 2 and 3, siblings with slightly different clinical presentations, were homozygous for a G-->A transition affecting the last nucleotide of exon 7 (628G-->A). This mutation resulted in amino acid substitution (E210K), as well as in multiple aberrant splice variants affecting exons 6 to 8. These observations expand the repertoire of LAMB3 mutations in nonlethal variants of EB, and they illustrate the consequences of the mutations at the mRNA and protein levels.

Integrin alpha 5 beta 1 expression is required for inhibition of keratinocyte migration by ganglioside GT1b

Polysialoganglioside GT1b, a keratinocyte membrane glycosphingolipid, inhibits normal keratinocyte adhesion and migration on a fibronectin matrix. The specificity of the inhibition for cells plated on a fibronectin matrix and competition of GT1b inhibition with peptide RGDS suggest that GT1b abrogates the alpha 5 beta 1/fibronectin interaction. We examined the effects of GT1b on the adhesion and migration of keratinocyte-derived cell lines and correlated GT1b responsiveness and alpha 5 beta 1 integrin expression. GT1b (5 nM) significantly inhibited migration of normal human keratinocytes, immortalized keratinocytes, and squamous cell carcinoma SCC12F2 cells on fibronectin, but not on collagen I. Concentrations as high as 5 microM had no effect on SCC13 or HaCaT cells. Likewise, GT1b inhibited fibronectin-dependent cell adhesion of normal human keratinocytes, immortalized keratinocytes, and SCC12F2 cells, but had no effect on SCC13 or HaCaT cells. Flow cytometric and Western immunoblot analysis of integrin expression showed significantly decreased alpha 5 and beta 1 integrin expression in SCC13 and HaCaT cells compared to normal keratinocytes, immortalized keratinocytes, and SCC12F2 cells. Incubation with TGF-beta 1 increased alpha 5 beta 1 integrin expression and induced responsiveness to GT1b in HaCaT cells. These data imply that GT1b "response" requires sufficient expression of alpha 5 beta 1 and further suggest that the mechanism of the inhibitory effect of GT1b involves GT1b/alpha 5 beta 1 interaction.

Partial albinism with immunodeficiency: Griscelli syndrome: report of a case and review of the literature

Partial albinism with immunodeficiency (Griscelli syndrome) is an uncommon disorder characterized by pigmentary dilution and variable immunodeficiency. Features include a silvery-gray sheen to the hair, large clumped melanosomes in hair shafts, and prominent mature melanosomes in cutaneous melanocytes with sparse pigmentation of adjacent keratinocytes. Immunologic abnormalities most often include impaired natural killer cell activity, absent delayed-type hypersensitivity, and impaired responses to mitogens. Impaired helper T cell function and hypogammaglobulinemia have also been described. The syndrome can be differentiated from Chediak-Higashi syndrome by pathognomonic light and electron microscopic features in skin and hair, and absence of consistent granulocyte abnormalities, but similarly carries a poor prognosis without bone marrow transplantation. We describe a patient with Griscelli syndrome who presented with hepatosplenomegaly, hepatitis, pancytopenia, and silvery hair in the newborn period.

Mucocutaneous manifestations of the hyper-IgM immunodeficiency syndrome

BACKGROUND

The recurrent pyogenic infections of patients with hyper-IgM syndrome are controlled by intravenous gamma globulin administration, but patients may suffer from early-onset oral ulcerations and warts.

OBJECTIVE

We have characterized the mucocutaneous manifestations associated with this condition to allow physicians to more readily identify it.

METHODS

Three male patients with the mucocutaneous manifestations of the hyper-IgM syndrome are described. In one, histopathologic examination of the oral mucosal lesion was performed.

RESULTS

Recurrent large, painful oral ulcerations can occur that are not necessarily associated with neutropenia nor do they respond to granulocyte colony-stimulating factor administration. Histopathologic examination of an ulcer showed a heavy infiltrate of mixed inflammatory cells. Warts tend to be widespread and resistant to traditional therapy.

CONCLUSION

Physicians should consider this uncommon condition when examining a male patient with severe oral ulcers or recalcitrant widespread warts.

Rat bite fever in a pet lover

Rat-bite fever is an uncommon bacterial illness resulting from infection with Streptobacillus moniliformis that is often transmitted by the bite of a rat. The cutaneous findings in rat-bite fever are nonspecific but have been described as maculopapular or petechial. We describe a 9-year-old girl with acrally distributed hemorrhagic pustules, fever, and arthralgias. Diagnosis was delayed because of difficulty in identifying the pathologic organism. She was successfully treated with 10 days of ceftriaxone.

Human angiostatin inhibits murine hemangioendothelioma tumor growth in vivo

Angiostatin inhibits angiogenesis and metastatic tumor growth; however, its usefulness in treating primary nonmetastasizing tumors is less well understood. We now report the effectiveness of human angiostatin administration in a mouse hemangioendothelioma model. Human angiostatin was administered to mice with s.c. hemangioendothelioma and associated disseminated intravascular coagulopathy (Kasabach-Merritt syndrome). Angiostatin significantly reduced tumor volume in comparison to nontreated controls, increased survival, and prevented the profound thrombocytopenia and anemia of Kasabach-Merritt syndrome. Apoptosis of tumor cells was induced by angiostatin, but tumor cell proliferation was not inhibited. These data suggest angiostatin as a novel treatment for nonmetastasizing vascular tumors and for Kasabach-Merritt syndrome.

Two cases of incontinentia pigmenti simulating child abuse

In the United States 1.4 million children were maltreated in 1988, resulting in an estimated 2000 to 5000 deaths. Largely due to the rising awareness and sensitivity to the horrors of child abuse, the number of deaths declined to approximately 1500 in 1993. Guidelines have been published to aid in the identification and management of child maltreatment, and reporting of all suspicious cases is mandated by law. In our zealous efforts to protect children, some families are investigated because of misdiagnosed abnormalities, often cutaneous, leading to the unintentional injury of both patients and their families. In this report, we describe two patients with cutaneous and/or visceral manifestations of incontinentia pigmenti (IP) who were initially thought to be victims of child abuse.