PubMed Health⌕ Search

Biomedical subjects

J Hunyadi

Publications and source records attributed to J Hunyadi.

At least 19 recordsLinked to original sources
PubMed2006

Significant correlation between the CD63 assay and the histamine release assay in chronic urticaria.

BACKGROUND: Antibodies directed to the alpha subunit of the high affinity IgE receptor and the IgE molecule are proposed to be of pathogenetic relevance in a group of patients with chronic urticaria (CU). The diagnosis of autoimmune chronic urticaria (ACU) is difficult; the autologous serum skin test (ASST) seems to be a useful screening test, but reliable, additional confirmatory methods are needed. OBJECTIVES: To assess the diagnostic value of a modified serum-induced basophil activation test, the CD63 expression assay, in the diagnosis of ACU by comparing the results of the CD63 assay with the results of the histamine release (HR) test, the ASST and serum levels of soluble CD40 ligand (sCD40L). METHODS: Using basophils from an atopic (DA) and a nonatopic (DNA) donor the activity of sera of 72 patients with CU were measured in HR assay by enzyme-linked immunosorbent assay and in CD63 expression assay by flow cytometry. An ASST was carried out in all patients; in 30 of the 72 patients sCD40L was detected and correlations were derived between the different assays. Sera of 20 normal controls and 26 patients with systemic autoimmune diseases were also tested in the HR assay and in the CD63 expression assay. RESULTS: Histamine-releasing activity was detected in the sera of 51% (DA) and 32% (DNA) of CU patients and 57% (DA) and 28% (DNA) of sera upregulated CD63 expression on the surface of basophils from the different donors. There was a significant correlation between the HR and the CD63 assays carried out on both donors, but the ASST showed a strong correlation with the HR assay only for basophils from the DA. The serum level of sCD40L was significantly higher in patients with CU compared with controls, but the difference between the autoimmune and the nonautoimmune groups was not significant. CONCLUSIONS: The CD63 expression assay seems to be a reliable functional test in the diagnosis of ACU, particularly if highly sensitive donor basophils are used, but the determination of the sCD40L serum level was not sufficient to differentiate between the autoimmune and the nonautoimmune patient groups.

Adolescent↗
PubMed2005

Altered cytokine expression of peripheral blood lymphocytes in polymyositis and dermatomyositis.

OBJECTIVE: To investigate the intracellular and soluble cytokine levels and T cell subsets in peripheral blood of patients with active and inactive polymyositis and dermatomyositis. METHODS: The frequencies of T and B lymphocytes, T helper (Th), and T cytotoxic (Tc) cells and of interferon gamma (IFNgamma), interleukin (IL)4, and IL10 expression of CD4+ or CD8+ cells were determined by flow cytometry. The concentrations of soluble cytokines were measured with commercial enzyme linked immunosorbent assays. RESULTS: In active dermatomyositis there was a decreased percentage of T (CD3+) lymphocytes and Tc (CD8+) lymphocytes, decreased IFNgamma expression of CD4+ and CD8+ cells, but an increase in B and IL4 producing CD4+ lymphocyte frequencies. These prominent changes disappeared in the inactive stage of the disease. In polymyositis no significant change in these lymphocyte subsets or in intracellular cytokine expression could be detected in either the active or the inactive form. The frequency of IL4+/IFNgamma+ Th cells was calculated and a significantly increased Th2/Th1 frequency was found in active dermatomyositis, and a decreased frequency in inactive dermatomyositis, compared with the control population. CONCLUSIONS: There appears to be a difference between polymyositis and dermatomyositis in the level of peripheral blood lymphocytes and their intracellular cytokine content. These findings provide further evidence for a difference in the pathogenesis of polymyositis and dermatomyositis.

Adolescent↗
PubMed2005

Ultraviolet-A1 phototherapy modulates Th1/Th2 and Tc1/Tc2 balance in patients with systemic lupus erythematosus.

OBJECTIVE: Ultraviolet-A1 (UVA1) phototherapy is effective for a variety of dermatological diseases. We examined the effectiveness and reliability of low-dose UVA1 phototherapy (60 kJ/m2/treatment) in patients suffering from systemic lupus erythematosus (SLE). We studied the changes in immunological parameters. METHODS: The patients received a 9-week course of phototherapy according to the following regimen: five times a week during the first 3 weeks, three times a week during the second 3 weeks and twice during the last 3 weeks. Among other things, we analysed the proportions of T helper 1 (Th1), Th2, T cytotoxic (Tc1) and Tc2 cell populations in the peripheral blood of patients by flow cytometric detection of intracytoplasmic interferon gamma (IFN-gamma) and interleukin 4 (IL-4). RESULTS: Our study showed the improvement of clinical symptoms determined by the subjective clinical disease activity scoring and the SLE Disease Activity Index (SLEDAI). By the end of UVA1 phototherapy, the mean value of SLEDAI had decreased from 7.2+/-5.6 to 0.9+/-1.8, which was significant (P = 0.005). Immunological investigations detected a decrease in the frequency of IFN-gamma-producing Th1 and Tc1 cells and a decrease in the Th1/Th2 and Tc1/Tc2 ratios after UVA1 therapy. CONCLUSION: According to the literature, IFN-gamma has a pathogenic role in the development of SLE. We observed a decreased proportion of IFN-gamma-secreting cells, which we think is presumably one of the beneficial effects of UVA1 therapy. On the basis of our study, UVA1 phototherapy does seem to be an effective adjuvant in the treatment of SLE patients.

Adult↗
PubMed2004

Association between the occurrence of the anticardiolipin IgM and mite allergen-specific IgE antibodies in children with extrinsic type of atopic eczema/dermatitis syndrome.

BACKGROUND: As the literature has only controversial data on the role of nonallergen-specific antibodies in atopic eczema dermatitis syndrome, the authors investigated the link between the occurrence of the antiphospholipid [anticardiolipin (ACL), anti-beta2-glycoprotein I] and allergen-specific immunoglobulin E (IgE) antibodies in 72 children with atopic eczema/dermatitis syndrome (AEDS). METHODS: The measurement of antiphospholipid antibodies was carried out by enzyme-linked immunosorbent assay (ELISA), serum total IgE by nephelometry, and allergen-specific IgE by immunoblotting assay. The statistical analysis was carried out by Fisher's exact test and odds ratio was calculated. RESULTS: Thirteen of 72 children with AEDS (mean age 8.3 years) had elevated serum levels of ACL, and eight anti-beta2-glycoprotein I antibodies. The presence of allergen-specific IgE against inhalant allergens and nutritive allergens was among eight of 13 and three of eight in the cases with elevated ACL. The ratio of patients with highly increased severity scoring of atopic dermatitis (SCORAD) index (>75) was significantly higher in the group with elevated (4/13) than in those with the normal ACL levels (2/59). There was a significant association between the appearance of mite (Dermatophagoides pteronyssinus, D. farinae)-specific IgE and ACL IgM antibodies (6/13). CONCLUSION: These findings show that there are significant linkage and association between the appearance of ACL IgM or the production of allergen-specific IgE against inhalant (mainly mite) allergens in children with atopic eczema/dermatitis syndrome.

Adolescent↗
PubMed2004

Basophil CD63 expression assay on highly sensitized atopic donor leucocytes-a useful method in chronic autoimmune urticaria.

BACKGROUND: The autoimmune subclass of chronic idiopathic urticaria (CU) has been characterized by the occurrence of biologically relevant IgG antibodies against the IgE molecule or the alpha chain of the high-affinity Fcepsilon receptor (FcepsilonRIalpha) on basophils and mast cells. These antibodies are usually detected by autologous serum skin testing and confirmed by histamine release studies, immunoblotting, or enzyme-linked immunosorbent assay, but not always. OBJECTIVES: To detect autoantibodies to the FcepsilonRIalpha in sera of CU patients by a modified serum-induced basophil activation test measured by flow cytometry (FCM) and to evaluate the relationship between the in vitro functional test, the autologous serum skin test (ASST), and the serum levels of IgE, eosinophil cationic protein (ECP) and antithyroid antibodies. METHODS: Sera of 30 patients with CU and 26 patients with systemic autoimmune diseases (systemic lupus erythematosus, dermatomyositis) were tested for CD63 activation marker expression on basophils by FCM. Leucocytes from two highly sensitized atopic donors (D(A1,) D(A2)) and one non-atopic donor (D(NA)) were incubated with patients' sera and double-labelled with anti-IgE and anti-CD63 antibodies. Subsequently, the percentage of CD63-expressing basophils was determined by using FCM. In all CU patients an ASST was carried out and the serum IgE, and ECP levels and antithyroid antibodies were evaluated. RESULTS: Twelve patients had a positive ASST and 14 patients a positive CD63 expression assay. There was a strong correlation between the ASST and CD63 assay. Sera from patients with systemic autoimmune diseases did not raise positive CD63 expression on basophils. There was a moderate negative correlation between the occurrence of atopic serum markers (IgE, ECP) and the ability of sera to induce CD63 expression on basophil cells of D(A2) (P < 0.05). The female sex was preponderant and antithyroid antibodies were more frequent. CONCLUSIONS: Our new technical observation demonstrates that basophils of highly sensitized atopic donors can be successfully used without priming with IL-3 for the in-vitro flow cytofluorimetric diagnosis of CU. With this investigation the characterization of the autoimmune origin of CU is based on an objective in vitro technique.

Adolescent↗
PubMed2002

Terbinafine (Lamisil) treatment of toenail onychomycosis in patients with insulin-dependent and non-insulin-dependent diabetes mellitus: a multicentre trial.

BACKGROUND: Diabetes mellitus (DM) affects an estimated 175 million people world-wide. Approximately one-third of patients with DM have toenail onychomycosis. OBJECTIVES: To determine the efficacy and safety of terbinafine treatment of toenail onychomycosis in patients with DM receiving insulin and/or oral antidiabetic agents. Special interest was focused on potential drug interactions with oral hypoglycaemic substances. METHODS: In a multicentre trial, patients suffering from insulin-dependent DM (IDDM) or non- insulin-dependent DM (NIDDM) with toenail onychomycosis were treated for 12 weeks with oral terbinafine 250 mg daily and followed up to 48 weeks. In addition to clinical, mycological and laboratory investigations, blood glucose levels were monitored. RESULTS: At the end of the trial (week 48), a mycological cure rate of 73% was achieved. The rates of clinical cure and complete cure (mycological cure plus clinical cure) were 57% and 48%, respectively. There was no statistically significant difference between the NIDDM and IDDM groups with respect to the cure rates (P > 0.05). No hypoglycaemic episode was reported and none of the patients had hypoglycaemia during the treatment phase. CONCLUSIONS: With excellent cure rates and a good tolerability profile, terbinafine should continue to be a drug of choice for the treatment of toenail onychomycosis in the rising number of NIDDM patients receiving multiple medication.

Adolescent↗
PubMed2002

Increased frequency of intracellular interleukin (IL)-13 and IL-10, but not IL-4, expressing CD4+ and CD8+ peripheral T cells of patients with atopic dermatitis.

BACKGROUND: A number of studies exist demonstrating the increased expression of type 2 cytokines and decreased capacity to produce interferon-gamma (IFN-gamma) in peripheral blood mononuclear cells (PBMCs) of patients with atopic dermatitis (AD). OBJECTIVES: To clarify the results of recent studies concerning the role of interleukin (IL)-4 and IL-13 in PBMCs of AD patients, we analysed the activation status of lymphocyte subpopulations. METHODS: We measured the intracellular expression and serum levels of certain type 1 and type 2 cytokines, using cell surface and intracellular cytokine staining, flow cytometry and enzyme-linked immunosorbent assay techniques. RESULTS: The frequency of IL-10 and IL-13 producing CD4+ and CD8+ T cells was significantly higher in patients with AD, while the frequency of IFN-gamma secreting helper and cytotoxic T cells was significantly lower in patients with AD than in control subjects. The serum levels of IL-10 and IL-13 were also significantly increased. There were no significant differences observed between the experimental groups in the frequency of IL-4 producing CD4+ and CD8+ cells. CONCLUSIONS: This study demonstrates a type 2 cytokine production in the CD4+ and CD8+ T cells of AD patients, which is characterized by an elevated IL-13, but not by IL-4 secretion, and by an increased level of the immunoregulatory IL-10, which can contribute to a decrease in IFN-gamma expression.

Adolescent↗
PubMed2002

Cimetidine and a tamoxifen derivate reduce tumour formation in SCID mice xenotransplanted with a human melanoma cell line.

Histamine is produced by many cells expressing histidine decarboxylase (HDC), the enzyme responsible for the synthesis of histamine. Since melanoma cells and tissue contain relatively large amounts of histamine, the functional significance of histamine was examined using specific antihistamines in vitro and in vivo in the human melanoma cell line HT168 and severe combined immunodeficiency (SCID) mice. It was shown that the H2 receptor antagonist cimetidine when combined with N, N-diethyl-2-[4-(phenylmethyl)phenoxy]-ethanamine-HCl (DPPE), a tamoxifen derivate, inhibits the proliferation of HT168 cells. Furthermore, it is suggested that there is a factor(s) that interferes with the exponential growth of HT168 cells xenografted to immunodeficient mice, and cimetidine and DPPE together significantly influence this factor(s). This combination of antihistamines also increases the survival of human melanoma-grafted mice. These changes are accompanied by enhanced infiltration of interferon-gamma- producing mouse macrophages into the tumour tissue. These findings suggest that two different mechanisms are probably acting concordantly: direct inhibition of tumour cell proliferation by the H2 receptor antagonists, and activation of the local immune response characterized by interferon-gamma production. These findings may help to elucidate the possibility of a rationally designed antihistamine strategy in melanoma therapy.

Animals↗
PubMed2001

Chromosomal imbalances in primary and metastatic melanomas revealed by comparative genomic hybridization.

Characteristic genetic changes underlying the metastatic progression of malignant melanoma is incompletely understood. The goal of our study was to explore specific chromosomal alterations associated with the aggressive behavior of this neoplasm. Comparative genomic hybridization was performed to screen and compare genomic imbalances present in primary and metastatic melanomas. Sixteen primary and 12 metastatic specimens were analyzed. We found that the pattern of chromosomal aberrations is similar in the two subgroups; however, alterations present only in primary and/or metastatic tumors were also discovered. The mean number of genetic changes was 6.3 (range 1-14) in primary and 7.8 (range 1-16) in metastatic lesions. Frequent losses involved 9p and 10q, whereas gains most often occurred at 1q, 6p, 7q, and 8q. Distinct, high-level amplifications were mapped to 1p12-p21 and 1p22-p31 in both tumor types. Amplification of 4q12-q13.1, 7q21.3-qter and 8q23-qter were detected only in primary tumors. The 20q13-qter amplicon was present in a metastatic tumor. The number of genetic alterations were significantly higher in primary tumors which developed metastases within one year after the surgery compared to tumors without metastasis during this time period. Fluorescence in situ hybridization with centromeric and locus-specific probes was applied to validate CGH results on a subset of tumors. Comparison of FISH and CGH data gave good correlation. The aggressive behavior of melanoma is associated with accumulation of multiple genetic alterations. Chromosome regions, which differ in the primary and metastatic lesions, may represent potential targets to identify metastases-related chromosomal alterations.

Adult↗
PubMed2001

Prevalence and age distribution of human herpesvirus-8 specific antibodies in Hungarian blood donors.

Sera of blood donors were investigated by a peptide ELISA and indirect immunofluorescence assay to assess the prevalence of HHV-8 infection in the Hungarian population. A 14 amino acid long synthetic oligopeptide from the carboxyterminus of orf65/small virus capsid antigen was used as antigen in the ELISA. ELISA results were confirmed by recombinant orf65 antigen Western blot. Antibodies to the latent nuclear antigen were detected by the immunofluorescence assay. Nine of 12 sera obtained from patients with classical Kaposi sarcoma were reactive by ELISA whereas all were positive by immunofluorescence. Four of 482 (0.83%) healthy blood donors had anti-orf65 peptide antibodies and 17/1089 (1.56%) had antibodies to the latent nuclear antigen. In a group of children ages 1-14 years, antibodies to the latent nuclear antigen (0/29) were not detected. The prevalence of antibodies to the latent nuclear antigen showed a moderate but significant increase in correlation with senescence. In the Kaposi sarcoma patients, the titre of antibodies to the latent nuclear antigen was significantly higher than in the healthy seropositive donors. The overall HHV-8 seroprevalence by the two assays was 2.28% (11/482) in the Hungarian blood donor group.

Adolescent↗
PubMed2001

UVB light and 17-beta-estradiol have different effects on the mRNA expression of Ro/SSA and La/SSB autoantigens in HaCaT cells.

Antibodies produced against the Ro/SSA and La/SSB autoantigens are not only of diagnostic value but they may even play a role in the pathogenesis of several autoimmune diseases (Sjögren's syndrome, subacute cutaneous lupus erythematosus, neonatal lupus erythematosus and systemic lupus erythematosus). Among other factors, ultraviolet (UV) radiation and also the hormonal milieu are well-known cofactors in the pathogenesis of these autoimmune diseases. The goal of our research was to study the possible alterations in mRNA levels of three different Ro antigens and that of two La species produced by alternative splicing in transformed human keratinocytes (HaCaT cells) after UVB irradiation and after 17-beta-estradiol treatment. The polymerase chain reaction technique was used to determine the mRNA levels of the Ro and La species after 24, 48, and 72 h of irradiation. The mRNA levels of calreticulin increased as a function of time after UV irradiation but the mRNA levels of 52 kDa and 60 kDa Ro mRNAs were unaltered. After treating the cells with 17-beta-estradiol, there was no change observed in the levels of Ro mRNAs or La exon 1 mRNA, but a gradual decrease was noted in the mRNA levels of La exon 1'. The importance of alterations in the ratio of La exon 1 to exon 1' is supported by the observations in patients with Sjögren's syndrome, and our results strengthen the notion that the Ro and La antigens participate in the pathogenesis of different autoimmune diseases.

Autoantigens↗
PubMed2001

HHV-8 ELISA based on a one-step affinity capture of biotinylated K8.1 antigen.

The immunogenic envelope antigen gp35-37 of human herpesvirus-8 (HHV-8) is encoded by orfK8.1. An ELISA is described using streptavidin capture of bacterially expressed and biotinylated recombinant K8.1 antigen. The antigen capture strategy provides a simple and reliable method, which does not require high yield production and purification of the recombinant antigen before the serological assay. The specificity and sensitivity of the K8.1 ELISA were validated by gp35-37 envelope antigen Western blot and anti-lytic membrane immunofluorescence assay using lytically induced HHV-8 infected BCBL-1 cells. Under the established ELISA conditions, eight of the 10 Kaposi's sarcoma patients and five of the 180 healthy blood donors had IgG antibodies to K8.1 envelope antigen.

Biotin↗
PubMed2001

Peroxynitrite production, DNA breakage, and poly(ADP-ribose) polymerase activation in a mouse model of oxazolone-induced contact hypersensitivity.

Peroxynitrite-induced poly(ADP-ribose) polymerase activation has been implicated in the pathogenesis of various inflammatory conditions. Here we have investigated whether peroxynitrite and poly(ADP-ribose) polymerase may play a role in the pathophysiology of the elicitation phase of contact hypersensitivity. We have detected nitrotyrosine, DNA breakage, and poly(ADP-ribose) polymerase activation in the epidermis of mice in an oxazolone-induced contact hypersensitivity model. As tyrosine nitration is mostly mediated by peroxynitrite, a nitric-oxide-derived cytotoxic oxidant capable of causing DNA breakage, we have applied peroxynitrite directly on mouse skin and showed poly(ADP-ribose) polymerase activation in keratinocytes and in some scattered dermal cells. We have also investigated the cellular effects of peroxynitrite in HaCaT cells, a human keratinocyte cell line. We found that peroxynitrite inhibited cell proliferation and at higher concentrations also caused cytotoxicity. Peroxynitrite activates poly(ADP-ribose) polymerase in HaCaT cells and poly(ADP-ribose) polymerase activation contributes to peroxynitrite-induced cytotoxicity, as indicated by the cytoprotective effect of the poly(ADP-ribose) polymerase inhibitor 3-aminobenzamide. The cytoprotective effect of 3-aminobenzamide cannot be attributed to inhibition of apoptosis, as apoptotic parameters (caspase activation and DNA fragmentation) were not reduced in the presence of 3-aminobenzamide in peroxynitrite-treated cells. Moreover, poly(ADP-ribose) polymerase inhibition by 3-aminobenzamide dose-dependently reduced interferon-induced intercellular adhesion molecule 1 expression as well as interleukin-1beta-induced interleukin-8 expression. Our results indicate that peroxynitrite and poly(ADP-ribose) polymerase regulate keratinocyte function and death in contact hypersensitivity.

Adjuvants, Immunologic↗
PubMed2000

Calcium release activated calcium entry in a human skin derived cell line (HaCaT).

Using isolated cells from a spontaneously immortalized human keratinocyte cell line (HaCaT) loaded with Fura-2 the regulation of intracellular Ca2+ concentration ([Ca2+]i) was studied. The continuous presence of ATP induced a biphasic response in high external Ca2+. The first component reflected the release of calcium from intracellular stores since it was present after the removal of external calcium with ethylene-glycol-bis-N,N,N',N'-tetraacetic acid (EGTA). The second phase of [Ca2+]i increase was not detectable in the absence of external calcium and raising the extracellular [Ca2+] increased the rate of rise in [Ca2+]i suggesting that it was influenced by the external environment. Furthermore, after adenosine triphosphate (ATP) had emptied the intracellular store in a calcium-free milieu, the elevation of external Ca2+ induced a secondary increase in [Ca2+]i that did not require the presence of ATP. Depleting the intracellular calcium store with a Ca-ATP-ase inhibitor (cyclopiasonic acid, 10 microM) also induced calcium entry. The depletion induced calcium entry was inhibited by econazole (100 microM). These findings indicate the presence of a calcium release activated calcium influx pathway in HaCaT keratinocytes.

Adenosine Triphosphate↗
PubMed1998

[Human herpesvirus-8 in Hungarian blood donors and in patients with Kaposi sarcoma].

The pathogenic role of Kaposi's sarcoma associated herpesvirus or human herpesvirus-8 in the development of Kaposi's sarcoma is widely accepted today. Here the authors report an indirect immunofluorescence assay based seroepidemiologic study. Their results indicate that 1.56% (17/1089) of the Hungarian adult population and 100% (12/12) of Kaposi's sarcoma patients have serum antibodies to HHV-8 latent nuclear antigens.

Adult↗
PubMed1998

[Lymphoblast transformation colorimetry in the diagnosis of drug hypersensitivity].

Diagnosis of drug allergy has been considered to be a multistage procedure consisting of detailed history of previous medication, analysis of symptoms, laboratory tests and provocation with the supposed sensitizing drug. Many laboratory methods are used for demonstration drug allergy, but opinions differ with regard to their specificity, sensitivity and reproducibility. Lymphocyte transformation test (LTT) is considered to be a valuable in vitro method in the diagnosis of drug allergy. For evaluation of LTT we introduced a tetrazolium-based colorimetric assay (MTT). Comparison of MTT assay with 3H-Thymidine incorporation in evaluation of Phytohaemagglutinin induced LTT resulted no significant difference in the dose-response curve. During the past 3 years 315 patients were tested with LTT-MTT method; 736 lymphocyte transformation tests mainly with antibiotics, topical anesthetics and painkillers were evaluated by MTT resulting 280 positive results. Physicians requested skin tests were performed with drugs induced no in vitro lymphocyte transformation and only 8 topical reactions without general symptoms were observed. MTT method was found to be a sensitive laboratory test in evaluation of LTT performable even in routine laboratories. Its application can lead to a substantial decrease in the number of patients who must be subjected to the possible risk of in vivo tests for the determination of the sensitizing drug.

Colorimetry↗
PubMed1998

Distinct subpopulations in HaCaT cells as revealed by the characteristics of intracellular calcium release induced by phosphoinositide-coupled agonists.

Intracellular calcium release induced by transient applications of phosphoinositide agonists was measured using adherent single HaCaT keratinocytes loaded with the acetoxymethyl derivative of fura-2. Application of ATP, bradykinin and formyl-Met-Leu-Phe (fMLP) resulted in a transient increase in intracellular calcium concentration ([Ca2+]i) with an average half-width of 40+/-21 s and a decay time constant of 15+/-10 s (mean +/- SD, n = 108), irrespective of the agonist applied. The cells could be classified into two groups: in 53% of the cells repeated stimulation brought about a progressively smaller change in [Ca2+]i (type 1 cells), whereas in the remaining cells the amplitude of the calcium transients was essentially unchanged (type 2 cells). Furthermore, calcium transients in type 1 cells had broader half-widths and slower decays. No difference was found between the agonists in respect of the characteristics of the evoked calcium transient within each subpopulation. However, bradykinin and fMLP desensitized some cells. These results indicate that the activation of the inositol trisphospate transduction pathway by different agonists induces a characteristic elevation of [Ca2+]i within a given cell. Our results demonstrate that cultured HaCaT keratinocytes are heterogeneous in respect of the calcium transients evoked by the activators of this second messenger system.

Adenosine Triphosphate↗