Phenytoin penetration into brain after administration of phenytoin or fosphenytoin

Paraneoplastic pemphigus (PNP) is an autoimmune blistering disease that occurs in association with underlying neoplasms. PNP patients develop characteristic autoantibodies directed against multiple antigens, mostly identified as members of the plakin family of cytoplasmic proteins (desmoplakin I and II, bullous pemphigoid antigen I, envoplakin, and periplakin). HD1/plectin, another member of the plakin family, has not previously been detected in the characteristic PNP antigen complex, which may relate to practical difficulties associated with its large size (molecular weight approximately 500 kDa). In this study, a combination of immunoprecipitation and immunoblot is used to demonstrate that HD1/plectin is also recognized by sera from PNP patients. Thirteen of 16 PNP sera tested were positive for HD1/plectin compared with none of 43 control sera (11 pemphigus vulgaris, 11 pemphigus foliaceus, 11 bullous pemphigoid, and 10 normal individuals). Combined with our recent finding that desmoglein 3 and desmoglein 1 are cell surface target antigens in PNP, this demonstration of plectin/HD1 as another component of the antigen complex in PNP confirms that PNP is an autoimmune disease against desmoglein and plakin family molecules.     

The pathophysiological significance of nondesmoglein targets of pemphigus autoimmunity. Development of antibodies against keratinocyte cholinergic receptors in patients with pemphigus vulgaris and pemphigus foliaceus

OBJECTIVES: To determine whether nondesmoglein (non-Dsg) autoantibodies are pathogenic and whether they recognize keratinocyte cholinergic receptors that control cell adhesion because antikeratinocyte autoimmunity in patients with pemphigus vulgaris is not limited to the development of autoantibodies to Dsg. DESIGN: To determine whether non-DSg autoantibodies are pathogenic, we sought to induce pemphigus in genetically engineered neonatal mice lacking Dsg 3 using pemphigus vulgaris IgGs that did not cross-react with Dsg 1. To determine whether pemphigus autoimmunity involves keratinocyte cholinergic receptors, the latter were separated from cell membranes of human keratinocytes, tagged with the covalent label [3H]propylbenzilylcholine mustard, and used as an antigen in a radioimmunoprecipitation assay of 34 pemphigus vulgaris and 6 pemphigus foliaceus serum samples. SETTING: The dermatologic clinics of the University of Minnesota, Minneapolis; the Mayo Clinic, Rochester, Minn; and the University of California-Davis Medical Center, Sacramento. PATIENTS: Serum samples were collected from 34 patients with pemphigus vulgaris and 6 patients with pemphigus foliaceus (aged 31-89 years) and from 7 age-similar patients of both sexes with nonpemphigus blistering or the following immune-mediated conditions: pemphigoid gestation, bullous drug eruption, lupus erythematosus, erythema nodosum, urticaria, acute contact dermatitis, and skin ulcers. MAIN OUTCOME MEASURES: Clinical, laboratory, and histopathologic findings. RESULTS: Extensive skin blistering accompanied by the Nikolsky sign and suprabasilar acantholysis was induced in the Dsg3null mice that received pemphigus, but not normal human IgGs. In the radioimmunoprecipitation assays for reactivity with cholinergic receptors, the mean radioactivity precipitated by pemphigus serum samples significantly exceeded both normal- and disease-control levels (P = .001-.02). The mean individual levels of radioactivity precipitated by 34 pemphigus vulgaris and pemphigus foliaceus serum samples (85%) exceeded control values by a mean of approximately 2.6 times. CONCLUSIONS: Autoantibodies to keratinocyte cell-surface molecules other than Dsg 1 and Dsg 3 can induce clinical features of pemphigus vulgaris. Patients with pemphigus vulgaris and those with pemphigus foliaceus develop IgG antibodies that precipitate radiolabeled cholinergic receptors. Because these receptors control keratinocyte adhesion and motility, their inactivation by autoantibodies may elicit intracellular signals that cause disassembly of desmosomes, leading to acantholysis and blistering.     

Targeted disruption of the pemphigus vulgaris antigen (desmoglein 3) gene in mice causes loss of keratinocyte cell adhesion with a phenotype similar to pemphigus vulgaris

In patients with pemphigus vulgaris (PV), autoantibodies against desmoglein 3 (Dsg3) cause loss of cell-cell adhesion of keratinocytes in the basal and immediate suprabasal layers of stratified squamous epithelia. The pathology, at least partially, may depend on protease release from keratinocytes, but might also result from antibodies interfering with an adhesion function of Dsg3. However, a direct role of desmogleins in cell adhesion has not been shown. To test whether Dsg3 mediates adhesion, we genetically engineered mice with a targeted disruption of the DSG3 gene. DSG3 -/- mice had no DSG3 mRNA by RNase protection assay and no Dsg3 protein by immunofluorescence (IF) and immunoblots. These mice were normal at birth, but by 8-10 d weighed less than DSG3 +/- or +/+ littermates, and at around day 18 were grossly runted. We speculated that oral lesions (typical in PV patients) might be inhibiting food intake, causing this runting. Indeed, oropharyngeal biopsies showed erosions with histology typical of PV, including suprabasilar acantholysis and "tombstoning" of basal cells. EM showed separation of desmosomes. Traumatized skin also had crusting and suprabasilar acantholysis. Runted mice showed hair loss at weaning. The runting and hair loss phenotype of DSG3 -/- mice is identical to that of a previously reported mouse mutant, balding (bal). Breeding indicated that bal is coallelic with the targeted mutation. We also showed that bal mice lack Dsg3 by IF, have typical PV oral lesions, and have a DSG3 gene mutation. These results demonstrate the critical importance of Dsg3 for adhesion in deep stratified squamous epithelia and suggest that pemphigus autoantibodies might interfere directly with such a function.     

A novel variant of acquired epidermolysis bullosa with autoantibodies against the central triple-helical domain of type VII collagen

Epidermolysis bullosa acquisita and bullous systemic lupus erythematosus are autoimmune bullous disorders, with tissue-bound and circulating autoantibodies reactive with the noncollagenous NC1 domain of type VII collagen (C-VII). Here, we describe a novel acquired bullous dermatosis with autoantibodies against the triple-helical domain of C-VII. Three patients, all Japanese children, presented with widespread inflammatory tense blisters. Histologically, subepidermal tissue separation was noted with inflammatory infiltrate in the superficial dermis. Direct immunofluorescence staining revealed linear IgG/C3 deposits along the dermal-epidermal junction. Circulating IgG anti-basement membrane zone autoantibodies stained the dermal side of normal skin separated with 1 M NaCl. Direct and indirect immunoelectron microscopy using colloidal gold labeling showed that patient sera reacted with anchoring fibrils. The gold particles were localized both near the lamina densa and on the central banded portion of the fibrils. The sera reacted with C-VII in immunoblots. Epitope analyses with natural and recombinant fragments of C-VII disclosed that the sera did not recognize the NC1 domain of C-VII, but the central triple-helical domain of this anchoring fibril protein. Thus, the present probands show a hitherto unrecognized variant of epidermolysis bullosa acquisita, with autoantibodies against epitopes in the collagenous domain of C-VII.     

A case of nonscarring inflammatory epidermolysis bullosa acquisita: characterization of IgG autoantibodies by immunofluorescence, immunoblotting and immunogold electron microscopy

We report a case of nonscarring inflammatory epidermolysis bullosa acquisita in a 59-year-old Japanese woman. She developed blisters and erosions on her lip, trunk and extremities. Sodium aurothiomalate was effective for the skin lesions. The patient had been free from bullous skin lesions for the last 13 years and had shown no scarring. Indirect immunofluorescence (IF) study on 1 M NaCl-split skin revealed IgG autoantibodies against the dermal side of the split skin. Immunoblotting using normal human dermal extracts disclosed IgG autoantibodies reactive with the 290 and 145 kD antigens. Circulating IgG autoantibodies were deposited on the lamina densa by immunoelectron microscopy. IF mapping using several antibodies for the components of the basement membrane zone revealed blister formation at the lamina densa. These results suggest that the cleavage at the lamina lucida does not necessarily exclude the diagnosis of EBA and that the definite diagnosis of EBA should be confirmed by immunoblotting or immunoelectron microscopic study.     

Development of pemphigus vulgaris-like lesions in severe combined immunodeficiency disease mice reconstituted with lymphocytes from patients

Pemphigus vulgaris is an autoimmune blistering disease that is induced by binding of antibodies to a 130/85-kD protein complex on epidermal keratinocytes. An in vivo experimental model of this disease was developed by reconstituting severe combined immunodeficiency (SCID) mice with 1-10 x 10(7) PBL from patients with naturally occurring pemphigus vulgaris. Of 49 reconstituted mice, 34 (69%) produced human IgG levels of > 0.1 mg/ml. Circulating anti-pemphigus antibodies were found in 20 of the 34 successfully reconstituted mice; 44% of these animals had deposits of human IgG in their own skin after it was traumatized by either heat or cold. Spontaneous pemphigus vulgaris-like blisters associated with human IgG deposits were rarely found in mouse skin. By contrast, allogeneic human skin grafted to 10 to 12 mice before reconstitution with patients' PBL developed pemphigus vulgaris-like lesions containing human IgG deposits. These results demonstrate that SCID mice can serve as a model of an antibody-mediated human autoimmune skin disease.     

Pemphigus with features of both vulgaris and foliaceus variants, associated with antibodies to 160 and 130 kDa antigens

We report an unusual variant of pemphigus in a 44-year-old man. He presented with scaly and crusted erosions associated with pruritic vesicles and erythema mainly on the chest, abdomen, back and face. Histology showed acantholysis with neutrophilic spongiosis in the granular layer and subcorneal region of the epidermis. Intercellular IgG in the epidermis was positive on direct immunofluorescence. Indirect immunofluorescence showed intercellular antibodies at a titre of 1 : 2 in the suprabasal epidermis. Circulating autoantibodies to 130 kDa and 160 kDa antigens were detected in the patient's serum by immunoblot analysis using epidermal extracts. These two antibodies eluted from individual nitrocellulose membranes reacted with the intercellular space in the epidermis on indirect immunofluorescence. This observation suggests that these antibodies correspond to desmogleins 3 and 1, respectively. The clinical symptoms almost completely disappeared after 28 days treatment with oral prednisolone (30 mg/day), leaving brown pigmented flecks on the lesional sites. These findings suggest that this patient's pemphigus has features of both the vulgaris and foliaceus variants, with antibodies against desmogleins 3 and 1.     

Linear immunoglobulin A (IgA) bullous dermatosis of childhood: identification of the target antigens and study of the cellular sources

A 4-year-old girl developed numerous tense blisters on the body. The blisters healed without scarring. Histopathological and immunofluorescence studies showed findings consistent with linear immunoglobulin A (IgA) bullous dermatosis of childhood. Immunoelectron microscopy revealed deposition of IgA in the lamina lucida of the basement membrane zone of the dermal-epidermal junction. Circulating IgA autoantibody was positive at the titre of 1 : 128 and recognized the antigens located on epidermal sites of 1 mol/l NaCl-split skin. Immunofluorescence staining of cultured normal human fibroblasts and cultured DJM-1 cells (derived from human squamous cell carcinoma of skin) with the patient's sera demonstrated that both of these cells synthesize the antigens in vitro, although fibroblasts produce the antigens more abundantly. When DJM-1 cells were injected intracutaneously into nude mice, the antigens recognized by the sera were present mainly around the tumour cell islands in a linear pattern, while the dermal-epidermal junction of mouse skin was negative, suggesting that epidermal cells may contribute directly to synthesis and deposition of the antigens at the basement membrane. By immunoprecipitation using cultured normal human fibroblasts, the patient's sera could precipitate at least two specific molecules at 100-kDa and 145-kDa molecular weight.     

Presence of anti-FKBP12 autoantibodies in patients with liver allografts: its association with allograft rejection

BACKGROUND: It was reported that autoantibodies against cyclophilin are present in sera from systemic lupus erythematosus. We hypothesized that autoantibodies against FKBP12, another immunophilin, may be present in the plasma of liver allograft recipients, which may affect the clinical outcome of liver allografts. METHODS: We investigated the relationship between the presence of anti-FKBP12 autoantibodies and rejection episodes in 47 patients treated with FK506 after living-related partial liver transplantation (LRLT). The patients consisted of two groups: 22 with rejection [R(+) group] and 25 without rejection [R(-) group]. The autoantibodies were measured by an indirect ELISA, and the specificity was confirmed by absorption with antigen and immunoblotting. RESULTS: The autoantibodies were detected in 13 of 22 in the R(+) group (IgG: 5; IgM: 6; both: 2) and in 6 of 25 in the R(-) group (IgG: 2; IgM: 3; both: 1) before LRLT (P=0.0193). After LRLT, they were also detected more frequently in the R(+) group (12 of 22; IgG: 1; IgM: 8; both: 3) than in the R(-) group (2 of 25; IgG: 1; IgM: 1) (P=0.001). In the R(+) group, the mortality of the patients who were positive and negative for the autoantibodies was 6 of 12 and 2 of 10, respectively. The autoantibodies were detected in all four patients with chronic or refractory acute rejection. The autoantibodies were not detected in any of the 34 healthy subjects. CONCLUSIONS: These results suggest that the presence of the autoantibodies in patients before transplantation is related to rejection, and the presence after transplantation may be associated with patient outcome.     

Community health in eastern Africa--and the East African Medical Journal''s contribution over seventy years

Antineutrophil antibodies may be found in the sera of patients with chronic neutropenia as well as in the sera of a variety of patients with neutropenia and associated autoimmune or infectious disorders. We evaluated an immunofluorescent flow cytometric technique for the measurement of antineutrophil antibodies in serum. Sera from patients with suspected immune neutropenia were studied and compared with a group of sera from normal healthy individuals, as well as with sera from patients with rheumatoid arthritis and systemic lupus erythematosus. Of 159 patients with suspected immune neutropenia and a variety of associated clinical disorders, 59 (37%) were found to have evidence for enhanced binding of IgG to normal target neutrophils, interpreted as positive for antineutrophil antibodies. Whereas 0/37 non-neutropenic patients with typical RA had positive results, 51/244 (21%) of sera from nonneutropenic patients with SLE or other collagen vascular disorders showed enhanced IgG binding to neutrophils. Living neutrophils were used to study the effects of cellular activation, and increased antibody binding was observed with certain sera that contained IgG directed against activation-dependent antigens. We found that, under controlled conditions, flow cytometry can be reliably used to detect antineutrophil autoantibodies, with unfixed, living neutrophils as antigenic targets.     

Isotype-specific immune responses in murine experimental anisakiasis

A murine experimental model of anisakiasis has been developed in BALB/c and C57BL/10 mice orally inoculated with an Anisakis simplex living third stage larva (L3) in order to investigate isotype-specific immune responses against excretory-secretory (ES) products and crude extracts (CE) from L3. Specific antibody production showed similar patterns against both ES and CE antigens with higher levels against the latter. The dynamics of the production showed the earliest responses in BALB/c, in which antibodies were principally of the immunoglobulin (Ig)M isotype. Responses to the IgG1 subclass were mainly produced in the C57BL/10 strain. Levels of IgG2a were practically undetectable. With sera from C57BL/10 mice high levels of the IgG2b isotype were detected. A slight IgG3 response was only detected against the CE antigen in the C57BL/10 strain by the end of the experiment and IgA responses were very low. Humoral responses against A. simplex antigens are different depending on individual characteristics and thymus-independent epitopes might be represented into A. simplex antigens and their stimuli could be different regarding the murine strain used.     

Detection of isotype-specific autoantibodies to calpastatin in sera from patients with rheumatic diseases using heat-treated HeLa cell extract as an antigen source for immunoblotting

To detect immunoglobulin isotype-specific autoantibodies to native human calpastatin in patients with rheumatic diseases, we performed immunoblot analysis using the heated HeLa cell extracts to enrich heat-resistant calpastatin. The calpastatin molecule that was apparently migrated to 110 kD by SDS-PAGE was confirmed to react with monoclonal anti-human calpastatin antibody in immunoblotting. IgG antibodies to calpastatin were detected in 22 of 48 sera (46%) from patients with RA, whereas only 20% (5/25), 11% (2/19) and 13% (2/15) of sera from SLE, SSc and PM/DM had IgG anti-calpastatin antibodies, respectively. IgM antibodies were also found in 40% (19/48) of RA and 12% (3/25) of SLE patients but not detected in sera from patients with other rheumatic diseases. IgA antibodies were found in only one RA and one SLE serum. In RA, 7 of 48 sera (15%) had IgM antibodies alone, but all SLE sera with IgM antibodies had IgG antibodies. Thus, anti-calpastatin autoantibodies were detected by using the native human calpastatin. Although these autoantibodies were found in patients with various rheumatic diseases, they were present in RA patients at the highest frequency. In particular, the presence of IgM antibodies appeared to be more specific in RA patients.     

Retina and retinal pigment epithelial cell autoantibodies are produced during murine coronavirus retinopathy

The murine coronavirus, mouse hepatitis virus (MHV), JHM strain, induces a biphasic retinal disease in adult BALB/c mice. In the early phase of the disease, day 1 to 7, a retinal vasculitis is noted and is associated with the presence of virus particles. In the late phase of the disease, day 10 to 140, a retinal degeneration is observed and is associated with the absence of both virus particles and inflammatory cells. We show that the retinal degenerative process is also associated with the presence of antiretinal autoantibodies. In total, 22 of 23 sera collected from 10 to 70 days after JHM virus inoculation contained antiretinal autoantibodies. These autoantibodies are not found in sera from normal or mock-injected mice. Antibodies to retinal tissue were identified as two distinct patterns of immunoperoxidase staining on frozen sections of normal rat eyes, retinal autoantibodies and retinal pigment epithelium (RPE) autoantibodies. The antiretinal autoantibodies first appeared as IgM class antibodies that shifted to IgG class autoantibodies. The anti-RPE cell autoantibodies were predominantly of the IgG class. Sera that were positive for these autoantibodies did not stain with liver or kidney sections but 2 of 3 did react with rat brain sections. A second mouse strain, CD-1, was also evaluated because these animals respond to JHM virus inoculation by developing only the early phase of this disease, i.e. vasculitis. On day 10 postinoculation, the retina architecture has a normal appearance. In these mice, which are free of a retinal degeneration, antiretinal autoantibodies are not produced. However, just as is noted in the BALB/c mice, antivirus neutralizing antibodies are produced in the infected CD-1 mice. These findings suggest a role for autoimmunity in the pathogenesis of murine coronavirus induced retinal degeneration. This study establishes an animal model for the study of humoral autoimmune responses in human retinal degenerations.     

Isotype responses to candidate vaccine antigens in protective sera obtained from mice vaccinated with irradiated cercariae of Schistosoma mansoni

In experimental schistosomiasis, sera of mice multiply vaccinated with radiation-attenuated cercariae of Schistosoma mansoni passively transfer resistance against cercarial challenge to naive mice. To further characterize these sera, we tested their protective capacities in two mouse strains (C57BL/6J and CBA/J) and compared the antigen-specific isotype compositions of the different protective sera by means of the enzyme-linked immunosorbent assay. By using an array of purified schistosomal antigens, the patterns of antibody titers and isotypes differed for each experimental group and antigen. In the most-protective C57BL/6J sera, high levels of immunoglobulin G1 (IgG1), IgG2a, and IgG2b bound to heat shock protein 70 and the integral membrane protein Sm23, whereas recognition of these antigens by less-protective CBA/J sera was lower. Glutathione S-transferase (GST) was recognized predominantly by IgM antibodies of all vaccinated groups, and a significant portion of this response was directed against carbohydrate epitopes. Antibodies specific for triosephosphate isomerase, paramyosin, and Sm32 (hemoglobinase) were present in less-protective sera and thus seem less relevant for passive transfer of resistance. The results of this study suggest a contribution of IgG antibodies specific for heat shock protein 70 and Sm23, and possibly a contribution of GST-specific IgM antibodies, to the protective effect of sera from C57BL/6J mice vaccinated with irradiated cercariae.     

Kinetics study and characterisation of target excreted/secreted antigens of immunoglobulin G, M, A and E antibodies from mice infected with different strains of Toxoplasma gondii

A kinetics study and characterisation of target excreted/secreted antigens of immunoglobulin (Ig) G, M, A and E antibodies were realised by Western blotting with immune sera of mice inoculated with three strains of Toxoplasma gondii: RH, C56 and S3. IgG antibodies of the immune sera recognised the major proteins of the three excreted/secreted antigen preparations with molecular masses of 30, 45, 63 and 77 kDa. IgM antibodies recognised proteins revealed by IgG antibodies but with variable intensities; some proteins were revealed during a short period. IgA antibodies did not recognise the 35-kDa antigen or the antigens inferior to 28 kDa. The RH excreted/secreted antigens were revealed with the highest intensity. The IgE antibodies were briefly detected in trace amounts during period from the 20th to the 35th day. The RH strain with its excreted/secreted antigens had the best antigenicity and is a good model for immunoprotection studies.     

Pharmacologic evidence for involvement of phospholipase C in pemphigus IgG-induced inositol 1,4,5-trisphosphate generation, intracellular calcium increase, and plasminogen activator secretion in DJM-1 cells, a squamous cell carcinoma line

The precise mechanism for acantholysis after pemphigus IgG binds to the cell surface is as yet unknown, although involvement of proteinases such as plasminogen activator (PA) has been suggested. We previously reported that pemphigus IgG, but not normal nor bullous pemphigoid IgGs, caused a transient increase in intracellular calcium ([Ca++]i) and inositol 1,4,5-trisphosphate (IP3) concentration in cultured DJM-1 cells (a squamous cell carcinoma line). To clarify whether phospholipase C is involved in this process after the antibody binds to the cell surface, we examined the effects of a specific phospholipase C inhibitor (U73122) on the pemphigus IgG-induced increase in [Ca++]i, IP3, PA secretion, and cell-cell detachment in DJM-1 cells. [Ca+2]i and IP3 contents were determined with or without 30-min pre-incubation with U73122 or an inactive analogue (U73343) with fura-2 acetoxymethylester and a specific IP3 binding protein, respectively. PA activity in the culture medium was measured after various incubation periods with pemphigus IgG by two-step amidolytic assay. The detachment of cell-cell contacts was examined by detecting the retraction of keratin filament bundle from cell-cell contact points to the perinuclear region by immunofluorescence microscopy using anti-keratin antibody. Pemphigus IgG immediately increased [Ca++]i and IP3 content. PA activity in the culture medium has also been increased at 24 h after pemphigus IgG was added in association with cell-cell detachment. However, pre-incubation with U73122 (1-10 microM), but not with U73343 (10 microM), dramatically reduced the pemphigus IgG-induced increases in [Ca++]i, IP3, and PA activity and inhibited the pemphigus IgG-induced cell-cell detachment. Both U73122 and U73343 caused no effects on cell viability and IgG binding to the cell surface. These results suggest that phospholipase C plays an important role in transmembrane signaling leading to cell-cell detachment exerted by pemphigus IgG binding to the cell surface.     

Affinity immunoblotting studies on the restriction of autoantibodies from endemic pemphigus foliaceus patients

Endemic pemphigus foliaceus or Fogo Selvagem (FS) is an autoimmune blistering skin disease mediated by autoantibodies directed against components on the surface of subcorneal keratinocytes. All patients have high titers of these autoantibodies in the IgG4 subclass as determined by indirect immunofluorescence on frozen skin sections. In addition, patients may also have autoantibodies in other IgG subclasses, particularly IgG1, but the titers in these subclasses are significantly lower than those found in the IgG4 subclass. We have now found that in addition to isotype preference, autoantibodies from FS patients show clonal restriction as evidenced by oligoclonal banding on isoelectric focusing after probing with extracts from both human and bovine epidermis. Both IgG1 and IgG4 exhibit oligoclonal banding, but the distribution of these bands in the pH gradient differs for these two subclasses. Whereas the IgG4 oligoclonal bands are distributed throughout the IgG4 pH range, IgG1 banding appears to be concentrated in the more basic region of the IgG1 pH range. This finding suggests that the IgG1 autoantibodies have undergone selective somatic mutation by a negatively charged autoantigen. Similar findings have been reported for pathogenic DNA autoantibodies associated with SLE. The wide distribution of IgG4 banding suggests that this response may have followed the IgG1 response and has not undergone selective mutation. Both IgG1 and IgG4 appear to be Ca++ dependent autoantibodies.     

Erythrodermic bullous pemphigoid is a clinical variant of bullous pemphigoid

Bullous pemphigoid (BP) is an autoimmune blistering disease of the skin. Several variants of BP have been described but until recently the relationship of these variants to generalized BP was unclear. Several studies have shown that pemphigoid nodularis, pemphigoid vegetans, localized BP and vesicular pemphigoid are true variants of BP as the circulating antibodies in these patients recognize the same 230 kDa BP antigen as found in patients with generalized BP. Erythrodermic BP is a very unusual variant characterized by an erythroderma along with blister formation. We describe the third known patient to develop erythrodermic BP and characterize the antigenic specificity of the circulating antibodies in both our newly reported patient with erythrodermic BP and in one of the two other previously reported cases of erythrodermic BP. Both patients with erythrodermic BP had circulating IgG antibodies which bound to the epidermal side of salt-split human skin in a pattern identical to two patients with immunopathologically proven generalized BP. Sera from four erythrodermic patients without blisters and from a healthy normal volunteer, as controls, failed to demonstrate detectable circulating IgF autoantibodies. Immunoprecipitation studies revealed that both patients with erythrodermic BP had circulating IgG autoantibodies which recognized, to varying degrees, the same 230 and 180 kDa BP antigens as recognized by sera from two patients with immunopathologically proven generalized BP. Sera from four erythrodermic patients without blisters and from a healthy normal volunteer, as controls, failed to recognize any specific polypeptides. These observations demonstrate that erythrodermic BP is a distinct clinical variant of BP.     

Identification of different circulating autoantibodies in patients with bullous pemphigoid and pemphigus vulgaris by means of immunoblotting

Immunoblotting studies with salt-split human epidermis were performed on sera from 15 patients with pemphigus vulgaris and 20 patients with bullous pemphigoid by using peroxidase-labelled antihuman IgG and IgA. Eleven sera of pemphigus vulgaris antigen. Most of the sera gave additional specific bands at 210 and 80 kD, with lower intensity. The sera of 4 patients, 3 of them were in clinical remission, did not yield specific bands. Seventeen sera of the 20 bullous pemphigoid patients yielded a 220-230 kD protein band against the major bullous pemphigoid antigen and 4 of them gave another specific band at 160-180 kD. Five sera produced multiple bands (220, 130, 100 and 75 kD). IgA antibodies against the major bullous pemphigoid antigen were demonstrated in 2 cases with IgA deposits along their basement membrane, as revealed by direct immunofluorescence. The immunoblot patterns correlated only weakly with the clinical findings in bullous pemphigoid. There was a considerable diversity in both clinical findings and immunoblot patterns.