A series of new replacement methods of skin irritation test such as EpiSkin, EpiDermSIT (updated) and SkinEthicRHE have been validated by ECVAM. Due to it, animals are protected to the full extent. These provide more methods for biological evaluation of medical devices.
Animal Testing Alternatives ; methods ; Humans ; Skin Irritancy Tests ; methods

The basophil activation test (BAT) has been suggested as a complementary method for diagnosing drug allergies. The aim of this study was to evaluate the clinical utility of this test in patients with drug-induced anaphylaxis. In total, 19 patients, all of whom had a history of moderate to severe anaphylaxis, were enrolled. None of the causative drugs had available in vitro tests or reliable skin tests; these drugs included, among others, first and second-generation cephalosporins, H2 blockers, and muscle relaxants. The BAT yielded positive results in 57.9% of the cases, which was similar those results of skin prick and intradermal tests (42.1% and 57.9%, respectively). When basophils were double labelled with CD63 and CD203c, both of which are basophil activation markers, the positive rate was increased from 57.9% to 73.7%. Therefore, the results of this study confirm that the BAT is a quick, reliable, and safe diagnostic tool for patients with drug-induced anaphylaxis.
Anaphylaxis* ; Basophils* ; Cephalosporins ; Drug Hypersensitivity ; Humans ; In Vitro Techniques ; Intradermal Tests ; Methods ; Skin ; Skin Tests

BACKGROUND AND OBJECTIVES: The skin prick test is a widely used test that uses three methods (allergen/histamine ratio method, erythema size method, and wheal size method) to interpret the results. However, there has been no comparison of these methods. The aim of this study is to compare the three different interpretation methods and define the relationship among them. SUBJECTS AND METHOD: A total of 139 patients who visited our allergy clinic complaining of nasal symptoms were enrolled. Three interpretation methods were used for defining positivity in the skin prick test, and their results were compared. The validity of each interpretation method was evaluated by total nasal symptom score. RESULTS: Positivity in the skin prick test was reported in 48.2% of patients according to the allergen/histamine ratio method and in 64.0% of patients according to the wheal size method and erythema size method. The proportion of subjects who showed a negative result with the allergen/histamine ratio method but positive results with the wheal size method or erythema size method was 15.8%. This group had a significantly higher total nasal symptom score, especially rhinorrhea and nasal obstruction, than subjects who showed negative results on all three methods. CONCLUSION: When diagnosing allergic rhinitis patients using the skin prick test, the wheal size method and erythema size method should be considered rather than the allergen/histamine ratio method.
Diagnosis ; Erythema ; Humans ; Hypersensitivity ; Methods* ; Nasal Obstruction ; Rhinitis, Allergic ; Skin Tests* ; Skin*

OBJECTIVETo evaluate the skin irritation and sensitization potential of the swine acellular dermal matrix treated with hyaluronic acid (SADM-HA).

METHODS(1) Skin irritation test. Twelve New Zealand rabbits were divided into SADM-HA group, allogeneic skin group, and (human) xeno-skin group according to the random number table, with 4 rabbits in each group. Four test sites were designed on the back of each rabbit. Two test sites of each rabbit in the three groups were covered with SADM-HA, allogeneic skin, and xeno-skin, respectively. Another test site was covered with gauze containing 200 g/L sodium dodecyl sulfate solution as positive control. The last test site was covered with gauze containing normal saline as negative control. The primary irritation index and cumulative irritation index of each material were calculated. (2) Skin closed-patch test. Sixty guinea pigs were used. Fifty-four guinea pigs were divided into SADM-HA group, allogeneic skin group, and (human) xeno-skin group according to the random number table, with 18 guinea pigs in each group. Twelve guinea pigs in each of the three groups were correspondingly induced and stimulated by SADM-HA, allogeneic skin, and xeno-skin, with 6 guinea pigs in each group treated with ethanol-soaked gauze to serve as negative control. The remaining 6 guinea pigs were treated with gauze containing 25% α-hexylcinnamaldehyde ethanol solution as positive control. The rating scales of Magnusson and Kligman were used to grade the condition of skin after being treated with above-mentioned materials to evaluate skin sensitivity to them at post stimulation hour 24 and 48. Data were processed with the non-parametric test of independent samples.

RESULTS(1) In the skin irritation test, the primary irritation indexes of the three dressings in SADM-HA group, allogeneic skin group, and xeno-skin group were respectively -0.04, 0.13, and 0.08. The cumulative irritation indexes of the three dressings in SADM-HA group, allogeneic skin group, and xeno-skin group were respectively 0.27, 0.10, and 0.25, which were close to those of negative control within the three groups. The skin irritation of each of the three materials was negligible. (2) In the skin closed-patch test, all scores of the three dressings in SADM-HA group, allogeneic skin group, and xeno-skin group were between 0 and 1. The scores of SADM-HA group and allogeneic skin group were close to those of negative control within the two groups (with U values respectively 188.00 and 90.00, P values both above 0.05). The differences were statistically significant between each material of the three groups and positive control (with U values respectively 19.00, 59.00, 21.50, P values all below 0.01).

CONCLUSIONSThe SADM-HA is safe and reliable without skin irritation and sensitization, and it has encouraging prospect in clinical application.

Acellular Dermis ; adverse effects ; Animals ; Guinea Pigs ; Hyaluronic Acid ; adverse effects ; Rabbits ; Skin ; Skin Irritancy Tests ; Skin Transplantation ; methods ; Swine

The pollen of Artemisia has been considered as the main late summer-autumn allergen source in this country. To identify its allergenic components, Artemisia princeps pollen extracts were separated by 10% sodium dodecylsulfate polyacrylamide gel electrophoresis (SDS-PAGE), and transferred to nitrocellulose membrane, where IgE binding components were detected by the reaction with sera of twenty Artemisia-allergic patients and 125I-anti-human IgE, sixteen components in the molecular range of 10,000 and 85,000 daltons were detected. Twelve bands bound to IgE from 50% of the sera tested, and two bands (37,000, 23,000 daltons) showed the highest (85%) frequency of IgE-binding in twenty sera tested. When the gel of SDS-PAGE with Artemisia pollen extracts was sliced into 11 allergenic groups (AG) and the protein of each AG was obtained by the gel elution method, the wormwool-RAST inhibition test showed that the AG 10 demonstrated to be the most potent, and the AG 7 was the next. Six AGs showed significant responses (more than 100% of wheal size to histamine, 1 mg/ml) on the skin prick test in more than 50% of the patients tested. It is suggested that electrophoretic transfer analysis with SDS-PAGE may be a valuable method for Artemisia allergen identification, and the possibility of partial purification of allergens by employing gel elution is discussed.
Blotting, Western/methods ; Electrophoresis, Agar Gel/methods ; Human ; Korea ; Lymphokines ; Plants/immunology ; Pollen/analysis/*immunology ; Skin Tests/methods

The pollen of Artemisia has been considered as the main late summer-autumn allergen source in this country. To identify its allergenic components, Artemisia princeps pollen extracts were separated by 10% sodium dodecylsulfate polyacrylamide gel electrophoresis (SDS-PAGE), and transferred to nitrocellulose membrane, where IgE binding components were detected by the reaction with sera of twenty Artemisia-allergic patients and 125I-anti-human IgE, sixteen components in the molecular range of 10,000 and 85,000 daltons were detected. Twelve bands bound to IgE from 50% of the sera tested, and two bands (37,000, 23,000 daltons) showed the highest (85%) frequency of IgE-binding in twenty sera tested. When the gel of SDS-PAGE with Artemisia pollen extracts was sliced into 11 allergenic groups (AG) and the protein of each AG was obtained by the gel elution method, the wormwool-RAST inhibition test showed that the AG 10 demonstrated to be the most potent, and the AG 7 was the next. Six AGs showed significant responses (more than 100% of wheal size to histamine, 1 mg/ml) on the skin prick test in more than 50% of the patients tested. It is suggested that electrophoretic transfer analysis with SDS-PAGE may be a valuable method for Artemisia allergen identification, and the possibility of partial purification of allergens by employing gel elution is discussed.
Blotting, Western/methods ; Electrophoresis, Agar Gel/methods ; Human ; Korea ; Lymphokines ; Plants/immunology ; Pollen/analysis/*immunology ; Skin Tests/methods

Humans ; Penicillins ; adverse effects ; immunology ; therapeutic use ; Skin Tests ; classification ; methods ; standards

BACKGROUNDThe cytotoxicity of dermal substitutes may be increased by the very processes used to deplete the cells. The present research aimed to investigate the method for monitoring the cytotoxicity of cell-free dermal substitutes using 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide (MTT) method.

METHODSThe cytotoxicity of four dermal substitutes was evaluated using the MTT method according to the standards set by the Chinese State Food and Drug Administration (SFDA). Swine acellular dermal matrix (SADM) and goat acellular dermal matrix (GADM) were produced using a repeated freeze-thaw method. Human dermal matrix glutaraldehyde composite (HADM-G) and SADM cross-linked with glutaraldehyde (SADM-G) were produced using conventional methods.

RESULTSThe cytotoxicity of all dermal substitutes ranged from Grade 0 to Grade 1, meeting the standards of the Chinese FDA. The OD(490) of both SADM and GADM was higher than that of either HADM-G or SADM-G (P < 0.05).

CONCLUSIONDermal substitutes produced by the freeze-thaw method are less cytotoxic than those produced using conventional methods.

Cell Line ; Humans ; Skin, Artificial ; adverse effects ; Tetrazolium Salts ; chemistry ; Toxicity Tests ; methods

Current asthma is often excluded by the presence of normal bronchial hyperresponsiveness. We report two asthmatic patients with normal bronchial hyperresponsiveness and one asthmatic patient with mild bronchial hyperresponsiveness (methacholine PC20; 24 mg/ml) which was presumed to be caused by sensitization and exposure to Black GR, the most frequent sensitizer among reactive dyes. They all complained of lower respiratory symptoms after work as well as at the workstation. The bronchoprovocation test with Black GR revealed isolated immediate bronchoconstrictions in all 3 patients and all had high specific IgE antibodies to Black GR-human serum albumin conjugate. After one worker continued at work for 3 days, he experienced a marked drop of methacholine PC20, and it returned to the pre-exposure level during 1 week. The other patient whose initial methacholine challenge was negative developed bronchial hyperresponsiveness on the first day after the dye bronchoprovocation, and returned to normal bronchial hyperresponsiveness on the third day. These findings suggested that patients with occupational asthma caused by reactive dye may not always have bronchial hyperresponsiveness to methacholine, and the screening program utilizing methacholine challenges may not always identify these patients.
Adult ; Asthma/*chemically induced ; Bronchial Provocation Tests/methods ; Bronchoconstriction/*drug effects ; Dyes/*adverse effects ; Human ; Hypersensitivity, Delayed ; Immunoglobulin E/analysis ; Male ; Occupational Diseases/*chemically induced ; Skin Tests

OBJECTIVETo evaluate the significance of several Dermatophagoides pteronyssinus allergen extracts for skin prick test (SPT) in patients allergic to Dermatophagoides pteronyssinus.

METHODSTwo hundred and nineteen patients enrolled in Peking Union Medical College Hospital underwent SPT and serum specific IgE assay to detect the Dermatophagoides pteronyssinus allergen. Three kinds of house dust mite allergen extracts were used for SPT, including the Dermatophagoides pteronyssinus extract prepared by our laboratory (group A), standardized Dermatophagoides pteronyssinus extract (group B), and mixed extracts of Dermatophagoides pteronyssinus and Dermatophagoides farinae (group C). Human serum specific IgE result was regarded as the reference standard for diagnosis of Dermatophagoides pteronyssinus allergy. The receiver operating characteristic (ROC) curve was used to evaluate the diagnostic performance of SPT with the extracts of three groups.

RESULTSSPT results showed that the median wheal diameter of group A, group B, and group C was 0.43, 0.35, and 0.28 cm, respectively, with significant difference among three groups (P<0.05). The difference was significant between group A and B (P<0.01) as well as group A and C (P<0.01), but not between group B and C (P>0.05). There was no local urticaria or systemic allergic reactions following the procedure of SPT. Local reaction was observed in 5 patients and delayed reaction was in 2 patients of group A. As for group B and C, local reaction occurred in 3 cases and delayed reaction in 2 cases in each group. The area under ROC curve of SPT with extract in group A, group B, and group C was 0.765, 0.801, and 0.782, respectively. Based on the detection results of serum specific IgE, the sensitivity of SPT in diagnosis of Dermatophagoides pteronyssinus allergy with extract of group A, group B, and group C was 92.4%, 87.0%, and 81.5%, and the specificity was 60.6%, 73.2%, and 74.8%, respectively.

CONCLUSIONThe Dermatophagoides pteronyssinus extract for SPT prepared by our laboratory offers good sensitivity and specificity comparable to commercially available allergen extracts, and it may be an appropriate candidate for clinical screening and diagnosis of Dermatophagoides pteronyssinus allergy.

Animals ; Antigens, Dermatophagoides ; immunology ; Dermatophagoides pteronyssinus ; immunology ; Female ; Humans ; Male ; ROC Curve ; Sensitivity and Specificity ; Skin Tests ; methods