Cryofibrinogenemia in a patient with B-cell lymphoma.

Cryofibrinogenemia is an uncommon cause of intravascular coagulation necrosis of the skin and occurs as a result of vascular occlusion from cryoproteins, which reversibly precipitate in cold temperatures. The disease is associated with various conditions, most commonly neoplastic and thromboembolic diseases, and produces cutaneous manifestations such as purpura, ecchymoses, gangrene, and ulcerations. Diagnosis is based on clinical cutaneous manifestations, histopathology, and the laboratory detection of cryofibrinogen precipitation. Treatment is based upon resolution of the underlying disease process or condition, although some interventions have been reported to have therapeutic efficacy. We discuss the presentation, diagnosis, and treatment of a case of cryofibrinogenemia in a patient with underlying B-cell lymphoma.

Systemic lupus erythematosus diagnosed during interferon alfa therapy.

We describe a patient who had clinical manifestations of several autoimmune disorders: Sjögren's syndrome, benign hypergammaglobulinemic purpura of Waldenström, and systemic lupus erythematosus (SLE). The SLE was diagnosed during therapy with interferon alfa. Testing for anti-Ro and anti-La antibodies was negative until the serum was diluted to eliminate a possible prozone phenomenon of antibody excess.

Recombinant desmoglein 3 has the necessary epitopes to adsorb and induce blister-causing antibodies.

The development of an animal model for studying the pathogenesis of pemphigus vulgaris (PV) has been hampered by the unavailability of the purified full-length autoantigen desmoglein 3 (Dsg 3).Therefore, we expressed Dsg 3 using a baculovirus expressed system. The expressed protein was identified as Dgs 3 by its reactivity with a pan-cadherin anti-serum, an anti-serum to a Dsg 3 synthetic peptide, or patient serum, and by amino-terminal sequencing. Carbohydrate analysis showed that recombinant Dsg 3 was glycosylated. While a majority of the recombinant protein was cell associated, by immunoprecipitation, some Dsg 3 was demonstrated in the medium. The Dgs 3 could adsorb out blister-causing antibodies from patient sera. Rabbit anti- Dsg 3 antibodies induced by the recombinant Dsg 3 showed specific binding to intercellular spaces of monkeys esophagus by indirect immunofluorescence. Moreover, these antibodies induced PV-like blisters in neonatal mice and weakly bound perilesional epidermis. Availability of large quantities of relatively pure Dsg 3 should now facilitate studies aimed at understanding Dsg 3 structure and pathogenesis of PV, with implications for developing specific immunotherapies.

Neonatal pemphigus foliaceus.

BACKGROUND: Pemphigus refers to a group of autoimmune blistering diseases of the skin. Of the two major types of pemphigus, pemphigus vulgaris and pemphigus foliaceus, only pemphigus vulgaris has been known to affect newborn infants via passive transfer of maternal IgG antibodies across the placenta. Although pemphigus foliaceus antibodies have also been shown to cross the placenta, never before has a newborn been clinically affected. We report the first of neonatal pemphigus foliaceus confirmed by both clinical presentation and immunofluorescence studies. OBSERVATIONS: The distinguishing factors in this case were high antibody titers by indirect immunofluorescence present in both the mother and her fetus (1:640 and 1:80, respectively). CONCLUSIONS: A threshold of fetal antibody titer ( > 1:40) may need to be surpassed before neonatal disease can occur in pemphigus foliaceus. The likelihood of reaching this threshold has been shown to be increased with higher maternal antibody titers. Thus, strict control of maternal pemphigus foliaceus should lower the incidence of placental antibody transfer and improve neonatal outcome.

Bullous pemphigoid autoantibodies reactive with intracellular basal keratinocyte antigens: studies of subclass distribution and complement activation.

Using immunofluorescence (IF) and monoclonal antibodies (MoAbs) to IgG subclasses, terminal complement components, and S-protein/vitronectin, we have extended recent observations concerning reactivity of bullous pemphigoid autoantibodies with intracellular antigens located on the polar tips of basal human keratinocytes (HuK). Using three purified bullous pemphigoid IgG fractions, autoantibody reactivity with these intracellular antigens was present in all four IgG subclasses. When skin sections were used as substrate, an identical IgG subclass distribution of autoantibodies for each bullous pemphigoid IgG fraction was observed, but reactive with the basement membrane zone. All three bullous pemphigoid IgG preparations contained IgG subclass autoantibodies capable of complement fixation. Each IgG fraction resulted in fixation of all of the terminal complement components (C5, C6, C7, C8, and C9) and assembly of the membrane attack complex (MAC) on the polar tips of basal HuK. S-protein/vitronectin was not bound in a similar fashion. Normal IgG fractions yielded consistently negative reactions. Thus, bullous pemphigoid autoantibodies, fixed to polar tips of basal HuK, are found in all four IgG subclasses and will activate complement resulting in generation of MAC.

The surgical applications and implications of cultured human epidermis: a comprehensive review.

Replacement of skin has long been the ultimate task for surgeons facing skin-resurfacing challenges such as thermal burns and chronic ulcerations. Autologous skin grafts have been the "gold standard" for wound closure, but in patients who are massively burned, the availability of normal skin is the limiting factor. In the past 15 years the technique of in vitro cultivation of human epidermis has been developed in an attempt to deal with the problem of extensive skin loss. Although the technique is costly and arduous, grafting patients who are severely burned with cultured epidermal autografts has proved to be a life-saving measure where few alternatives exist. Cultured allografts have promoted rapid healing and pain relief in patients with chronic ulcers. Although longer follow-up is necessary, recent evidence suggests that cultured epidermis provides a wound cover that is just as durable and esthetically acceptable as conventional split-thickness skin grafts. This article reviews the development and applications of epidermal cell culture.

Once-daily naftifine cream 1% in the treatment of tinea cruris and tinea corporis.

Seventy patients with tinea cruris or tinea corporis were treated with naftifine cream 1% or vehicle once daily for 4 weeks in this double-blind, randomized study. After two weeks, the patients using naftifine had a significantly higher mycologic cure rate than the vehicle-treated patients (79% vs. 31%, p less than 0.001), and they showed significantly better resolution of signs and symptoms. Statistically significantly differences favoring naftifine over its vehicle were found throughout the treatment period and 2 weeks posttreatment.

Pemphigus immunoglobulin G subclass autoantibodies: studies of reactivity with cultured human keratinocytes.

The subclass distribution of pemphigus vulgaris (PV) autoantibodies has been investigated further. Cultured human keratinocytes (HuKs) were incubated with immunoglobulin G (IgG) fractions prepared from the serum samples of five patients with PV and one patient with pemphigus foliaceus (PF). The binding of IgG subclasses to HuK was detected by the use of indirect immunofluorescence done with monoclonal antibodies that were specific for each of the four human IgG subclasses. IgG1 and IgG4 binding to keratinocytes was detected in all of the pemphigus IgG preparations. In each instance, the titer of bound IgG1 was equal to or greater than the IgG4 titer. IgG3 binding was detected in only one PV IgG, and IgG2 pemphigus antibody activity was not detected. Differences in the immunofluorescence patterns between the five PV and one PF IgG and between the five PV and a second PF serum were noted. PV antigens were detected as a speckled pattern on HuKs, with accentuation in the intercellular spaces. By comparison, the pattern of PF antigen expression varied significantly depending on whether anti-IgG1 or anti-IgG4 antisera were used. Anti-IgG1 bound in a coarse granular pattern without accentuation in the intercellular spaces, but anti-IgG4 bound in a pattern nearly identical to that observed with PV IgG and its subclasses.

Chronic cutaneous lupus erythematosus.

Chronic cutaneous LE is a diverse disease, characterized by predominantly cutaneous disease with few systemic complications. Discoid lesions are commonly seen, but they are not specific for chronic cutaneous LE. These scarring and disfiguring changes are also present in neonatal LE, SLE, and complement deficiency LE. Because definitive diagnosis cannot be made by cutaneous examination alone, all patients should initially be evaluated for systemic disease. A small percentage of patients with chronic cutaneous LE will ultimately develop SLE, and therefore, patients should be re-evaluated periodically. The pathogenesis of the cutaneous lesions is not definitively known. There is suggestive evidence implicating T-cell mediated injury, especially in discoid LE. Antibody-dependent cellular cytotoxicity may also play a significant role in cellular damage in subacute cutaneous LE and neonatal LE, especially in the presence of anti-Ro antibody. Immunoglobulin deposition in association with membrane attack complex, has been associated with epidermal injury in some cases. Treatment of chronic cutaneous LE is largely symptomatic and nonspecific, focusing on reduction of inflammation. Further knowledge of pathogenesis will, hopefully, provide for specific immunologic therapy.

Deposition of the membrane attack complex of complement in pemphigus vulgaris and pemphigus foliaceus skin.

The present study was performed to determine whether complement activation in pemphigus vulgaris (PV) and pemphigus foliaceus (PF) results in the assembly of the terminal complement sequence or membrane attack complex (MAC) in skin lesions. Biopsy specimens of skin lesions from five patients with PV and three patients with PF contained C5, C7, C9, and the MAC related neoantigen (C5b-9 neoantigen) in intercellular substance areas (ICS), as well as IgG and the early complement components Clq, C4, and C3. The presence of these late complement components and the C5b-9 neoantigens in ICS sites of the skin lesions is indicative of complement activation by the pemphigus antibody, with subsequent assembly of the MAC. The binding of IgG and early complement components to ICS was observed in both non-lesional (normal appearing) skin and in skin lesions. However, no MAC could be detected in the normal appearing skin of our pemphigus patients. It was also noted that the MAC could be generated in vitro on cryostat sectioned normal human skin by pemphigus antibody in the presence of complement. Results of these studies suggest that complement activation may be related to membrane damage of epidermal cells in both PV and PF.

Humoral immunopathological mechanisms in the skin.

Thus the skin is a unique organ in terms of location. Our skin directly interfaces with our environment and thus, unlike any other organ, is constantly subjected to foreign substances and microorganisms. Many of its structures are unique, and many of the proteins expressed by epidermal cells are also unique. Exposure to ultraviolet light affects the expression of some of these proteins as well as other biochemical substances. Although the skin also functions as an immunologic organ, it is not surprising that it can be the subject of immunologic attack. Thus, all of the major humoral immune mechanisms, cytotoxic or cytolytic, immune complex and atopic or anaphylactic, are manifested in terms of skin diseases.

Complement fixation by pemphigus antibody. V. Assembly of the membrane attack complex on cultured human keratinocytes.

Previous studies have shown that pemphigus vulgaris (PV) IgG will fix early complement components (C1q, C4, and C3) to cultured murine epidermal cell surfaces and that PV IgG and complement alter epidermal cell membrane integrity. The present study was undertaken to determine if assembly of terminal complement components (C5, C6, C7, C8, and C9) and expression of C5b-9 neoantigens occur when PV IgG interacts with human keratinocyte (HuK) cell surface antigens in the presence of a source of complement. Monoclonal antibodies specific for C5, C6, C7, C8, C9, and C5b-9 neoantigens were screened for reactivity to the individual complement components in an assembled complex of human C5b-9 on rabbit red blood cell ghosts. Monoclonal antibodies (tissue culture supernatants) that bound to antigenic determinants accessible in the C5b-9 complex were selected for this study using immunofluorescence methods. HuK treated with PV IgG fixed C5, C6, C7, C8, C9, and C5b-9 neoantigens in a characteristic speckled pattern, while normal IgG did not. Heat inactivation or EDTA treatment of the complement source, or substitution of C2-depleted serum abolished C5, C6, C7, C8, C9, and C5b-9 neoantigen staining. PV IgG and complement also resulted in significant cytotoxicity to cell membranes as assessed using an ethidium bromide-fluorescein diacetate assay. These results suggest that PV IgG will activate the membrane attack complex of the complement system on HuK cell surfaces, resulting in cytotoxicity to cell membranes, further implicating complement in the pathogenesis of pemphigus.

Expression of pemphigus vulgaris antigen in cultured human keratinocytes: effect of inhibitors, tunicamycin, and lectins.

We have investigated expression of pemphigus vulgaris antigen(s) in cultured human keratinocytes induced by the addition of extracellular calcium. Cycloheximide (10(-4) M) inhibited pemphigus antigen expression and stratification but actinomycin D (2 micrograms/ml) had no effect. Tunicamycin, which inhibits dolichol pyrophosphate-mediated glycosylation of asparaginyl residues specifically, was used to study the role of glycosylation. When calcium switching was carried out in the presence of tunicamycin, human keratinocytes did not stratify, and the expression of pemphigus antigen was partially inhibited and limited to cell-cell contact areas. Analysis of biosynthetically labeled proteins showed that the synthesis of high-molecular-weight proteins was markedly reduced in the tunicamycin-treated cells. A reciprocal blocking test demonstrated that concanavalin A and wheat germ agglutinin receptor share an epitope with pemphigus vulgaris antigen(s). These results suggest that Ca++, newly synthesized protein, and N-asparaginyl glycosylation are required for normal pemphigus antigen expression and epidermal stratification in vitro. Pemphigus vulgaris antigen may have a highly glycosylated, high-molecular-weight protein chain with carbohydrates playing an important role in epidermal cell morphology, adhesion, and stability of cell surface antigens.