Biomedical subjects

J Fransson

Publications and source records attributed to J Fransson.

At least 19 recordsLinked to original sources

PubMed2002

Many-body approach to spin-dependent transport in quantum dot systems.

By means of a diagram technique for Hubbard operators, we show the existence of a spin-dependent renormalization of the localized levels in an interacting region, e.g., quantum dot, modeled by the Anderson Hamiltonian with two conduction bands. It is shown that the renormalization of the levels with a given spin direction is due to kinematic interactions with the conduction subbands of the opposite spin. The consequence of this dressing of the localized levels is a drastically decreased tunneling current for ferromagnetically ordered leads compared to that of paramagnetically ordered leads. Furthermore, the studied system shows a spin-dependent resonant tunneling behavior for ferromagnetically ordered leads.

Journal Article↗

PubMed2002

Langerhans cells that express matrix metalloproteinase 9 increase in human dermis during sensitization to diphenylcyclopropenone in patients with alopecia areata.

BACKGROUND: We know little of the initial events during the sensitization phase of contact allergy in humans. Alopecia areata (AA), a disease of unknown pathogenesis characterized by patchy hair loss, may be treated by inducing contact allergy to diphenylcyclopropenone (DPC), later followed by its topical application. OBJECTIVES: To learn more about the initial events during sensitization in human skin, we studied the early events during induction of contact allergy to DPC in patients with AA. METHODS: DPC 2% and sodium lauryl sulphate (SLS) 4% were applied on the backs of eight patients with AA. Punch biopsies were taken 6 and 24 h after application. The biopsies were snap-frozen and cryostat sections were evaluated with immunohistochemistry using antibodies against CD1a, HLA-DR, CD3, CD54 and matrix metalloproteinase 9 (MMP-9). RESULTS: After 24 h all subjects exhibited erythema on the DPC-treated areas. Histological evaluation of biopsies from these areas showed hydropic degeneration and a significantly increased number of MMP-9+ cells in the dermis (P < 0.0005). The MMP-9+ cells were identified with double immunofluorescence staining as CD1a + Langerhans cells. The expression of the other markers studied remained unaltered irrespective of treatment, including treatment with SLS. CONCLUSIONS: Our findings show that DPC induces an irritant reaction leading to an increased number of MMP-9+ CD1a+ cells in the dermis during the initial phase of sensitization.

Administration, Topical↗

PubMed2000

Proliferation and effects of UVA irradiation in cultured fibroblasts from lesions in cutaneous lupus erythematosus.

Cutaneous lupus erythematosus (LE) often presents clinically as chronic cutaneous lesions, healing with scar formation, and acute cutaneous lesions that are seen in systemic and subacute LE and heal without scarring. UV-light plays a role in the pathogenesis of the skin lesions, but the pathomechanism is still unclear. The aim of this study was to compare fibroblast proliferation and response to UV-light by cultured fibroblasts from scarring and non-scarring LE lesions. Fibroblasts were cultured from skin lesions from 5 patients with classic discoid LE, 5 patients with subacute cutaneous LE and healthy, age-matched donors. Proliferation rate was assessed by cell counts at days 3, 6 and 9. The fibroblast cultures were irradiated with UVA and the supernatants were analysed for IL-6, TGF-beta, IL-4, soluble ICAM-1 and soluble VCAM-1. Fibroblast cultures from scarring lesions showed significantly lower cell-counts at days 3 (P = 0.01) and 9 (P = 0.009), than cultures from nonscarring lesions or controls. There were no significant differences in levels of IL-6 or TGF-beta in supernatants of irradiated fibroblasts from patients compared to controls and IL-4 and the soluble forms of ICAM-1 and VCAM-1 were below detection level. The response to UV-irradiation was similar to that of normal cells in the parameters studied. In summary, cultured fibroblasts from scarring LE lesions displayed significantly decreased proliferation rates compared to non-scarring LE lesions and controls. This may be secondary to inflammatory factors, or due to a functional defect in LE fibroblasts.

Cell Division↗

PubMed1999

Psoriatic fibroblasts secrete lower amounts of IL-6 than healthy fibroblasts before and after stimulation with TNF-alpha.

Altered function of the fibroblasts is thought to contribute to the pathogenesis of psoriasis. To further elucidate this point, we compared the ability of fibroblasts from psoriatic lesions and of fibroblasts from healthy individuals to produce interleukin-6 (IL-6). The IL-6 levels were measured by ELISA in serum-free culture medium before and after stimulation of monolayer fibroblasts with various concentrations of tumour necrosis factor-alpha (TNF-alpha), platelet-derived growth factor (PDGF), and interferon-gamma (IFN-gamma), alone and in different combinations. The production of IL-6 in the fibroblast cultures was stimulated by TNF-alpha (0.01-10 nm/ml medium) in a dose-dependent way. Fibroblasts from psoriatic lesions produced lower amounts of IL-6 than fibroblasts from healthy individuals both before and after stimulation with the different concentrations of TNF-alpha (P = 0.012). The ratios between the IL-6 concentrations before and after stimulation with TNF-alpha were similar in both types of fibroblasts, indicating that the capacity to produce IL-6 is reduced in psoriatic fibroblasts compared with healthy ones. The production of IL-6 was not influenced by either PDGF or IFN-gamma. These findings support the view that the phenotype of the fibroblast is altered in psoriasis.

Adult↗

PubMed1999

Localization of interleukin-13 gene-expressing cells in tuberculin reactions and lesional skin from patients with atopic dermatitis.

Interleukin (IL)-13 is a cytokine thought to play an important role in IgE-mediated allergic reactions. The aims of the present study were to localize IL-13 mRNA in positive tuberculin reactions and atopic dermatitis lesions using in situ hybridization and to study the possible influence of atopy on the cytokine gene expression in tuberculin reactions. Punch biopsy specimens were taken from tuberculin reactions in 17 nonatopic and 12 atopic (Phadiatop positive), but otherwise healthy, individuals 72h after injection of purified protein derivative, from chronic lichenified lesions and nonlesional skin in six patients with atopic dermatitis and from normal skin in 12 healthy individuals. IL-13-mRNA-producing cells were located mainly in the dermal-cell infiltrates, both in atopic dermatitis lesions and tuberculin reactions. In the atopic dermatitis lesions, IL-13-mRNA expression was found in close apposition to the epidermis. Higher numbers of IL-13-mRNA-producing cells were observed in the dermal-cell infiltrates of chronic lichenified skin lesions of patients with atopic dermatitis (13.3 cells/mm2, range 0.6-42.4 cells/mm2) than in the tuberculin reactions (1.1 cells/mm2, range 0-3.8 cells/mm2) (P<0.01) despite the larger cell infiltrates in the tuberculin reactions. No significant difference in IL-13 or interferon-gamma gene expression in the tuberculin reactions was seen between atopic and nonatopic individuals.

Adolescent↗

PubMed1998

Culture of human epidermal Langerhans cells in a skin equivalent.

Langerhans cells (LCs) have been cultured in a skin equivalent (SE). Seventy-two SEs were produced by inserting skin biopsies from nine subjects into dermal equivalents consisting of fibroblasts in a collagen matrix. The SEs were cultured in a serum-free medium containing 2-mercaptoethanol with or without 5 ng/mL granulocyte-monocyte colony-stimulating factor (GM-CSF). The SEs were cultured for 12 or 15 days. In the latter case, 0, 1 or 10 microg/mL cyclosporin A (CyA) was added for the last 3 days. The SEs were then snap frozen for immunohistochemistry. The migration of LCs was evaluated by measuring the distances from the inserted skin biopsy in the SEs to the HLA-DR + and CD1a+ dendritic cells localized at the longest distance from the biopsy in the epidermal outgrowth on both sides of the biopsy. The density of these cells was estimated in 15-day-old SEs by counting them on both sides of the inserted skin biopsy and dividing the number of positive cells by the migrated distances. All epidermal outgrowths (range 0.6-3.7 mm) were well differentiated and displayed HLA-DR+, CD1a+ and Lag+ dendritic cells. Only occasionally were CD83+ cells observed. In the 15-day-old SEs cultured with GM-CSF, a few CD86+ cells were seen in the epidermal outgrowths and occasionally CD80+ cells. The median (n = 4) density of CD1a+ and HLA-DR+ cells in the epidermal outgrowths at day 15 was 5.2 and 9.1 cells/mm, respectively. GM-CSF did not influence migration in 12-day-old SEs, but there was a tendency to increased migration of HLA-DR+ dendritic cells in 15-day-old SEs. CyA did not affect migration or density. We conclude that LCs can be cultured with an in vivo-like density in a SE. They express the phenotype of immature antigen-presenting cells efficient in capturing and processing antigen. This model may be suitable for studies of the initial phase of contact allergic reactions.

Cells, Cultured↗

PubMed1997

Solvent effects on the solubility and physical stability of human insulin-like growth factor I.

PURPOSE: The solubility and physical stability of human Insulin-like Growth Factor I (hIGF-I) were studied in aqueous solutions with different excipients. METHODS: The solubility of hIGF-I was determined by UV-absorption and quantification of light blocking particles. The physical stability of hIGF-I was studied with differential scanning calorimetry (DSC) and circular dichroism (CD) spectroscopy. RESULTS: Human IGF-I precipitated at low temperature in the presence of 140 mM benzyl alcohol and 145 mM sodium chloride. CD data showed that the tertiary structure of hIGF-I during these conditions was perturbed compared to that in 5 mM phosphate buffer. In the presence of benzyl alcohol 290 mM mannitol stabilized hIGF-I. Sodium chloride or mannitol by themselves had no effect on either the solubility or the tertiary structure. Benzyl alcohol was attracted to hIGF-I, whereas sodium chloride was preferentially excluded. The attraction of benzyl alcohol was reinforced by sodium chloride leading to salting-out of hIGF-I. The CD-data indicated interactions of benzyl alcohol with phenylalanine in hIGF-I. Thermal denaturation of hIGF-I occurred in all solutions with sodium chloride, whereas mannitol or benzyl alcohol had no effect on the thermal stability. The thermal stability of hIGF-I was thus decreased in 145 mM sodium chloride although it was excluded from hIGF-I. CONCLUSIONS: The self-association and thermal aggregation of hIGF-I is driven by hydrophobic interactions. Benzyl alcohol is attracted to hIGF-I and induces changes in the tertiary structure causing hydrophobic attraction of the protein at low temperatures.

Benzyl Alcohols↗

PubMed1997

IL-13 over-expression in skin is not confined to IgE-mediated skin inflammation.

IL-13 is produced by T cells and, like IL-4, it can induce the production of IgE and IgG4. In order to investigate if IL-13 is a specific marker for atopic dermatitis (AD), IL-13 gene expression was analysed in chronic lichenified lesions and non-lesional skin of patients with AD, in involved and non-involved skin of patients with psoriasis, in positive tuberculin reactions in non-atopics, and in the skin of healthy control subjects. Patients with AD (n = 9) showed sensitization to common air-borne allergens (positive Phadiatop) and had total serum IgE values in the range from 10 to 4800 kU/l (median 170 kU/l). Competitive reverse transcription-polymerase chain reaction (RT-PCR) was used to assess IL-13 gene expression in skin biopsy specimens. IL-13 gene expression was markedly higher in chronic lichenified lesions of patients with AD (P < 0.01), and in the positive tuberculin reactions (P < 0.01; n = 12) than in skin from healthy control subjects (n = 10). However, there was no significant difference in IL-13 gene expression in the skin of patients with psoriasis (n = 10) and that of healthy control subjects. The dermal cell infiltrates were larger and the relative amount of CD3+ and CD4+ cells in these infiltrates was higher in the skin of subjects with a positive tuberculin reaction than in lichenified AD skin. However, these differences were not reflected in differences in IL-13 gene expression. Different triggers of IL-13 gene expression may influence the diverse patterns of inflammation seen in different inflammatory skin disorders.

Adolescent↗

PubMed1997

Elevated serum levels of soluble CD30 in patients with atopic dermatitis (AD).

The immunopathology of AD is still unclear, but evidence for an immune response polarized towards Th2 activity has been provided. The CD30 molecule belongs to the tumour necrosis factor (TNF) receptor family and is expressed on activated T cells with a sustained expression in Th2 cells. This molecule also exists in a soluble form (sCD30). Elevated serum levels of sCD30 have been found in patients with Hodgkin's disease, chronic hepatitis B infection and HIV infection. Studies were undertaken to compare the serum levels of sCD30 in patients with AD (n=49) and healthy non-atopic controls (n=94). The presence of sCD30 was analysed with ELISA. A significantly higher concentration of sCD30 was noted in AD patients, median sCD30 level 29 U/ml (range 1-708 U/ml), compared with healthy non-atopic controls (P<0.001), where the median level was 11 U/ml with a range of 1-1042 U/ml. No correlation was found between sCD30 levels and total serum IgE, or between the AD patients' SCORAD values and concentration of sCD30. sCD30 levels were also analysed in 20 AD patients, which during ketoconazole treatment had improved their clinical scores and reduced their serum IgE and eosinophil cationic protein levels. However, no significant decrease in sCD30 levels was noted after treatment. The results show that patients with AD have elevated levels of sCD30, but without correlation to total serum IgE or disease activity.

Adolescent↗

PubMed1997

RT-PCR topography of chronic psoriasis skin based on analysis of T-cell receptor B variable region gene usage.

Psoriasis is a hyperproliferative inflammatory disease and 70% of patients develop a chronic plaque form. The pathogenesis of psoriasis is not known but evidence exists that T cells play a crucial role. The T cell V-gene receptor repertoire from psoriasis skin (different layers) was compared with peripheral blood T cells by employing RNA polymerase chain reaction (PCR) amplification. T cell receptor (TCR) BV 5.1, 11, 12, 13.1 and 16 were utilized to a significantly higher degree in areas close to the basal layers when compared to CD4+, CD8+ or unfractionated blood T cells from the same patients, whereas only BV11 and 13.1 genes of T cells from deeper layers of the dermis showed such a skewed usage. No biased usage of TCRBV genes was observed in superficial layers or in whole skin. Furthermore, T cell receptor junctional diversity analysed by high resolution gel electrophoresis showed skin psoriatic T cells to be poly- or oligoclonal. In conclusion, we show that TCRBV gene usage from different layers of psoriatic skin has a different pattern compared with the corresponding gene usage in circulating peripheral blood T cells. This pattern may implicate possible skin-associated antigen or superantigens activating a limited number of T cells in areas of skin close to basal layers, which in turn could promote keratinocyte proliferation.

Antigens↗

PubMed1996

The effect of IFN-gamma on healthy and psoriatic keratinocytes in a skin equivalent model is influenced by the source of the keratinocytes and by their interactions with fibroblasts.

We investigated the effect of interferon-gamma (IFN-gamma) on skin equivalents. Keratinocytes from involved and uninvolved skin from psoriatic subjects and from healthy subjects were grown on preproduced dermal equivalents (DE) containing fibroblasts from healthy skin or psoriatic lesions. Healthy keratinocytes were added when the dermal equivalents were either 22 days (DE(22)) or 37 days old (DE(37)) and psoriatic keratinocytes when the dermal equivalents were 28-52 days old (DE(28-52)). The skin equivalents were cultured for 11 days in a serum-free medium, and then with or without 500 U/ml IFN-gamma for 6 days. The expression of markers associated with differentiation and proliferation were investigated by immunohistochemistry. Differentiation was assessed by computed scores for the expression of cytokeratin 16, involucrin, filaggrin and the receptor for epidermal growth factor. The differentiating effect of IFN-gamma on healthy keratinocytes grown on DE(37) was significantly stronger than on psoriatic keratinocytes grown on DE(28-52). In healthy keratinocytes, the differentiating effect of IFN-gamma was significantly stronger in skin equivalents containing DE(37) than in those containing DE(22). The proliferation rate, i.e. the percentage of Ki-67+ keratinocytes in the basal layer, was studied in healthy keratinocytes grown on DE(22). In these cultures IFN-gamma increased the proliferation rate in the presence of psoriatic fibroblasts but not in the presence of healthy fibroblasts. HLA-DR expression was induced only in healthy keratinocytes grown on DE(22). We conclude that the influence of IFN-gamma epidermal differentiation and proliferation is influenced by the origins of both the keratinocytes and the fibroblasts. These findings suggest that interactions between keratinocytes and fibroblasts might be involved in the pathogenesis of psoriasis.

Adult↗

PubMed1996

Oxidation of human insulin-like growth factor I in formulation studies, II. Effects of oxygen, visible light, and phosphate on methionine oxidation in aqueous solution and evaluation of possible mechanisms.

PURPOSE: The oxidation of methionine in human Insulin-like Growth Factor I (hIGF-I) in aqueous solution was studied with respect to oxygen, visible light and sodium phosphate. METHODS: Aqueous solutions of hIGF-I were prepared with different amounts of phosphate and dissolved oxygen. The solutions were stored either in darkness or exposed to artificial visible light. The oxidized hIGF-I was quantified by RP-HPLC. A two level full factorial experimental design, with two levels of each of the three factors studied, was used. RESULTS: Oxidation was found to be positively correlated with light oxygen content and, interestingly, phosphate. The increasing effect of phosphate on the oxidation appears not to originate from metal contaminants. The influence of both oxygen and phosphate increased with time. The pH dependence of oxidation indicated the formation of a phosphorylated sulfonium ion as an oxidation intermediate. A significant interaction effect between phosphate and visible light suggested participation of radicals. CONCLUSIONS: Factorial experiments provide a valuable tool when studying complex mechanisms with interacting factors. The oxidation of methionine in hIGF-I is significantly affected by light but also by the presence of phosphate buffer.

Chemistry, Pharmaceutical↗

PubMed1996

Oxidation of human insulin-like growth factor I in formulation studies: kinetics of methionine oxidation in aqueous solution and in solid state.

PURPOSE: The aim of this work was to study the kinetics of oxidation of methionine in human Insulin-like Growth Factor I (hIGF-I)1 in aqueous solution and in the solid state by the aid of quantification of oxygen. METHODS: The oxidized from of hIGF-I was characterized by tryptic peptide analysis, RP-HPLC and FAB-MS and quantified by RP-HPLC. The oxygen content was quantified polarographically by a Clark-type electrode. RESULTS: Second-order kinetics with respect to amount of protein and dissolved oxygen was found to be appropriate for the oxidation of methionine in hIGF-I. The rate constants ranged from 1 to 280 M-1 month-1 and had an activation energy of 95 (+/-4) kl/mole. Light exposure, storage temperature and oxygen content were found to have a considerable impact on the oxidation rates. No significant difference in reaction rates was found for the oxidation of hIGF-I in aqueous solution or in the solid state. A method for decreasing the oxygen content in aqueous solution without purging is described. CONCLUSIONS: Polarographic quantification of dissolved oxygen makes it possible to establish the kinetics for oxidation of proteins. The oxidation of methionine in hIGF-I appears to follow second-order kinetics.

Amino Acid Sequence↗

PubMed1996

Local tolerance of subcutaneous injections.

Human insulin-like growth factor I (hIGF-I) has several possible clinical applications. Because subcutaneous administration of the drug can cause pain, local tolerance to injection of different formulations with or without hIGF-I has been investigated in man using isotonic saline solution as reference. The formulations, made isotonic with NaCl, ranged in pH from 6 to 7 with phosphate buffer concentrations of 5 to 50 mM. The local tolerance after injection was assessed as injection pain on a visual analogue scale, pain duration and local tolerance (redness, paleness and oedema). The discomfort at the injection site was lowest with 10 mM phosphate, pH 7. Injection of buffer at pH 6 (50 mM phosphate) caused significantly more pain than using 10 mM phosphate, whereas the pain at pH 6 using 10 mM phosphate did not differ significantly from that experienced on injection of the solution at pH 7 using either 10 or 50 mM phosphate. hIGF-I itself did not seem to cause pain. We concluded that for subcutaneous injections at non-physiological pH, the buffer strength should be kept as low as possible to avoid pain upon injection. We also hypothesize that when a non-physiological pH must be used for stability reasons, a lower buffer strength enables more rapid normalization of the pH at the injection site.

Adolescent↗

PubMed1995

Proliferation and interferon-gamma receptor expression in psoriatic and healthy keratinocytes are influenced by interactions between keratinocytes and fibroblasts in a skin equivalent model.

Epidermal-dermal interactions were studied in a skin equivalent model. Six combinations of keratinocytes and fibroblasts from healthy and psoriatic skin were used. TPA (12-O-tetradecanoylphorbol-13-acetate) was used to determine whether the expression of the IFN-gamma receptors in keratinocytes was related to epidermal differentiation and proliferation. These phenomena were assessed by immunohistochemistry. In all epidermal outgrowths, the epidermal growth factor receptor was expressed throughout the epidermis, cytokeratin 16 suprabasally, and filaggrin and involucrin in its superficial part. The IFN-gamma receptor was expressed throughout the epidermis, but was unevenly distributed. The expression of the IFN-gamma receptor was quantified by confocal laser scanning microscopy both in the whole of epidermis and in areas with the strongest intensity. The total amount varied to a minor degree in the epidermal outgrowths of different origins and was unaffected by TPA. In high-intensity areas interactions between keratinocytes and fibroblasts did influence the amount of IFN-gamma receptor expression and TPA decreased the expression by 13%. There was no correlation between the proliferation rate and the expression of the IFN-gamma receptor. Psoriatic and healthy keratinocytes were equally well differentiated in the skin equivalents. The interferon-gamma receptor was similarly expressed under these conditions. The growth rate, assessed by Ki-67-positive nuclei in the basal layer, was highest in healthy keratinocytes. Keratinocytes from psoriatic lesions increased their growth rate when cocultured with psoriatic fibroblasts compared with normal ones, indicating that fibroblasts may be of importance for epidermal hyperproliferation in psoriatic lesions.

Adult↗

PubMed1992

Epidermal growth in the skin equivalent.

The skin equivalent (SE) has been validated as a model for studies on proliferation of keratinocytes. SEs were prepared from normal skin by implanting punch biopsies on dermal equivalents consisting of fibroblasts in a collagen matrix. The outgrowths were measured by planimetry. An immunohistochemical investigation with antibodies against markers associated with proliferation was performed on frozen sections from SEs during outgrowth at 3-6 days (SE6) as well as after completion of outgrowth at 21 days (SE21). Biopsies from normal controls and from uninvolved and involved skin in psoriatic patients were also studied. The antibodies used were Ki-67, cytokeratin 8.12, and antibodies against the receptors for epidermal growth factor (EGFr) and transferrin (TFr). The increase in area was linear during the first 7 days of culture and usually reached the edges of the dermal equivalent at this time. In SE6 TFr was expressed in the basal part of the outgrowth while the other markers were not observed. In SE21 and in psoriasis there was abundant epidermal staining of Ki-67-positive nuclei and cytokeratin 8.12 was detected in the suprabasal part of the epidermis. EGFr and TFr were seen in the basal layer in SE21. In the psoriatic lesions these receptors were found both in the basal and suprabasal layers. The lack of proliferation markers in SE6 indicates that the initial increase in the area of keratinocytes is due to migration from the punch biopsies. Increased cell proliferation is present in SE21, a finding in common with psoriasis and wound healing. The skin equivalents should therefore be an appropriate model for studies on these phenomena.

Adult↗

PubMed1992

Expression of interferon-gamma receptors in normal and psoriatic skin.

Psoriatic keratinocytes have a reduced antiproliferative response to interferon (IFN)-gamma, and HLA-DR expression is usually not observed on keratinocytes in psoriatic plaques despite the presence of activated T cells. We have therefore compared the expression of IFN-gamma receptors in psoriatic skin with that of normal human skin. Using mouse monoclonal antibodies and immunoperoxidase staining on cryostat cut sections, we detected IFN-gamma receptors on keratinocytes throughout the epidermal layers except stratum corneum in normal skin (n = 11). Biopsy specimens from involved psoriatic skin (n = 17) consistently showed a staining pattern that differed from that of normal skin in that only the lower part of epidermis reacted with the antibodies to IFN-gamma receptors, whereas the upper layers showed no or minimal staining. Expression of IFN-gamma receptors in uninvolved psoriatic skin (n = 16) did not differ from that of healthy controls. Forty-five percent of the biopsies from lesional psoriatic skin displayed ICAM-1 positive keratinocytes, and only two specimens had a limited expression of HLA-DR reactive keratinocytes. The decreased binding of antibodies against the IFN-gamma receptors in the upper part of psoriatic epidermis might be secondary to abnormal maturation of psoriatic keratinocytes or a primary defect involving abnormal modulation of IFN-gamma receptors.

Adult↗

PubMed1990

The specificity and cellular origin of phenylethanolamine N-methyltransferase (PNMT)-like immunoreactivity in psoriatic skin.

Phenylethanolamine N-methyltransferase (PNMT)-like immunoreactivity has been found in psoriatic skin and in this study, PNMT-like immunoreactivity was investigated in the involved and uninvolved skin of six patients with lichen planus and four patients with lichen simplex. No PNMT immunoreactivity was observed in these diseases. Studies were carried out using cultured fibroblasts from two patients with psoriasis from uninvolved and involved areas of skin and from two controls using antibodies to PNMT, as well as antibodies to the chemical messengers somatostatin, substance P, parathyroid hormone and peptide histidine isoleucine amide. No immunoreactivity to these substances was found, and fibroblasts are unlikely to be the cellular origin of the PNMT-like immunoreactivity as seen in psoriatic skin.

Adolescent↗