Study on Skin Irritation of Clobetasone Butyrate Cream in Rabbits and Its Skin Sensitization in Guinea Pigs / 中国药房

OBJECTIVE：To study the skin irritation and se nsitization of domestic generic drug Clobetasone butyrate cream ， and to compare it with commercial drug （original drugs ）. METHODS ：The skin irritation test was conducted on rabbits. Totally 24 rabbits were randomly divided into test preparation intact skin group ，test preparation abraded skin group ，commercial drug intact skin group and commercial drug abraded skin group ，with 6 rabbits in each group. 0.5 mL test preparation or commercial drug was administered to the left side of intact or abraded skin and the same amount of excipient on the right side of each rabbit twice a day for consecutive 7 days. The irritation of the drug to the rabbit skin was observed ，and the erythema and edema of the skin were scored；the skin of administration site was taken at 72 h after last administration and the end of 7 d after drug withdrawal for histopathological examination. The skin sensitization test （Buehler test ）was carried out on guinea pigs. Totally 60 guinea pigs were randomly divided into test preparation group （n＝20），commercial drug group （n＝20），positive control group （n＝10）and excipient control group （n＝10）. 0.2 mL test preparation or commercial drug was administrated to the left side of the rib abdomen skin of each guinea pig at the 0，7th，14th day to induce model ，and an equal amount of corresponding preparation was administered to the right side in the same way at the 28th day for stimulation. Hypersensitive response such as erythema and edema were observed and scored at 24 h and 48 h after the stimulation. The incidence of hypersensitive response was then calculated. RESULTS：In skin irritation test of rabbits ，no erythema and edema was caused by the test preparation or commercial drug on intact skin of rabbits ；scores of skin irritation was 0；there was no dermal irritation. Both test preparation and commercial drug caused transient slight erythema on abraded skin of a few rabbits ；scores of intact and abraded skin irritation were 0-0.33；there was no dermal irritation. There was no statistical significance among groups. No dermal pathological changes were observed. In skin sensitization test of guinea pig ，no hypersensitive response such as erythema and edema was found on the skin of guinea pigs in both test preparation and commercial drug groups ；both score and the incidence of hypersensitive response were 0. Compared with excipient control group ，there was no statistical significance of average score and the incidence of hypersensitive response in test preparation group and commercial drug group. CONCLU- SIONS：In skin irritation test of rabbits and skin sensitization test of guinea pigs ， the evaluation results of generic Clobetasone butyrate cream are the same as those of the original drug. It has no irritation to the skin of rabbit ，and no sensitization to the skin of guinea pigs.

In vitro method for skin sensitization based on dendritic cell activation / 中国比较医学杂志

Allergy contact dermatitis is a type IV delayed type hypersensitivity that is induced by exogenous compounds and involves many cell types. Traditional animal testing uses guinea pigs or mice as a model. With progress of the adverse outcome pathway(AOP)on skin sensitization, a concept for development of alternative methods based on a molecular initiating event and key events is provided. Dendritic cell(DC)activation plays a key role in the AOP. Many alternative methods have been developed,with several methods validated and accepted as guidance for assays. This paper examines DC screening, characteristics of test parameters, and limitations and applicability of DC-derived methods. Progress on interactions between DCs and other cells, co-culture systems, and the human body-on-a-chip will also be introduced. Altogether,this paper will provide information for optimization of in vitro alternative methods for sensitization detection.

Predicting the sensitizing potency of trichloroethylene by in vitro test / 中国职业医学

OBJECTIVE: To predict the sensitizing potency and optimal sensitization dose of trichloroethylene( TCE) by an in vitro skin sensitization test on a human acute monocytosis cell line( THP-1).METHODS: THP-1 cells were cultured in vitro and exposed to 2,4-dinitrochlorobenzene( DNCB),sodium dodecyl sulfate( SDS),tert-butylhydroquinone( tBHQ)and TCE for 24 hours.Flow cytometry was used to detect the expression of cell surface marker such as cluster of differentiation( CD) 86 and CD54,and the optimal dose range for sensitization detection was determined.With the relative fluorescence intensity( RFI),CD86 ≥ 150 and CD54 ≥ 200 as the standard,the sensitizing potency and optimal sensitization dose of TCE were predicted.RESULTS: The concentration range of reagents for sensitization test on THP-1 cells was the dose range at which the relative cell survival rate reached 75.0%-100.0%.DNCB at the doses of 20.83,25.00 and 30.00 μmol/L,tBHQ at the dose of 5.80 μmol/L,TCE at the doses of 8.33,10.00 and 12.00 mmol/L,can cause sensitivity.SDS was recognized as a negative sensitizer.The expression of CD86 and CD54 was the highest when the concentration of TCE was 8.33 mmol/L,which was considered as the best sensitization dose.CONCLUSION: The optimum sensitization dose of TCE is 8.33 mmol/L,which can provide the basis for dose design in future study of TCE sensitization pathways.

An in vitro skin sensitization test based on THP-1 cell line / 中国比较医学杂志

Objective To establish an in vitro skin sensitization test,human cell line activation test (h-CLAT),based on THP-1 cell line (a human acute monocytic leukemia cell line),and to assess the sensitizing potency of plant raw materials of chemical and cosmetic products by this in vitro skin sensitization test.Method THP-1 cells were cultured in vitro and exposed to 11 reference skin sensitization chemicals and 9 samples,by monitoring the cell viability,cell surface marker CD54 /CD86 and relative fluorescence intensity of cells surface after the cells was exposures to the substances,and to discover whether there is a positive reaction.At the same time,Buehler test was used to validate the results of samples tested by h-CLAT.Results 11 reference chemicals were distinguished correctly by h-CLAT.Among the 9 samples tested,7 samples were recognized as negative sensitizer and 2 plant extracted substances were identified as suspicious skin sensitizer.The qualitative classification of the 9 samples by h-CLAT test was consistent with the results obtained by animal test.Conclusions The h-CLAT-in vitro test can be used to replace some animal tests for the prediction of soluble skin sensitizing substances.

Research progress of alternative in vitro methods to evaluate skin sensitization / 中国比较医学杂志

Skin sensitization (allergic contact dermatitis, ACD), is a serious condition caused by small reactive molecules and is characterized by a delayed-type hypersensitivity .Animal tests were usually used in the evaluation of sensitizing potential of chemical substances in the past .However , there is an increasing interest from the public for reducing and ultimately replacing animal tests .The European Union (EU) has posed a ban on animal testing of cosmetic ingredients that includes skin sensitization since 2013.Therefore, alternative in vitro tests are the main tendency in chemical substances and cosmetic sensitizing potential research in the future .In this study, different kinds of in vitro test methods that were adopted by OECD or on research (LLNA, DPRA, KeratinoSens TM, h-CLAT) were reviewed through recent years literature , comprehensive introduction and evaluation were made to obtain reliable hazard and potency information on potential skin sensitizers .

Preliminary study for integrating DPRA with h-CLAT to predict skin sensitizers / 中国实验动物学报

Objective To establish a detection method integrating DPRA ( direct peptide reactivity assay) with h?CLAT ( human cell line activation test) to screen the skin sensitization potency of chemicals and plant extracts. Methods 12 chemicals and 7 plant extracts were chosen as the test substances. Firstly, the test substances were incubated together with two different peptides ( cysteine and lysine) respectively for reaction for 24 h. The peptide consumptions were analyzed by HPLC. Simultaneously, THP?1 cells were cultured in vitro and then exposed to different concentrations of test sub?stances for 24 h to examine the cell viability, cell surface markers CD54 and CD86 were assessed by flow cytometry. The predicting results were compared further between DPRA and h?CLAT. Results 12 chemicals were distinguished correctly by DPRA classified as 2 non?sensitizers and 10 sensitizers. The results of DPRA were in accordance with h?CLAT. Predic?ting the sensitization potency of plant extracts by DPRA showed that 6 plant extracts were determined as suspected sensiti?zers except for green tea extract. But using the method of h?CLAT, 4 plant extracts were examined as suspected sensitizers except for green tea extract, herba portulacae extract and ginseng fruit extract. The coherence of DPRA and h?CLAT was 0?57. Conclusion This detection method integrating DPRA with h?CLAT can predict single compound accurately. As for complex compound, it can achieve preliminary prediction and need other integrating methods to make a further identifica?tion.

Safety Study of Polyisobutylene Gutong Plaster by Transdermal Administration / 中国药房

OBJECTIVE:To investigate the safety of Polyisobutylene (PIB) Gutong plaster by transdermal administration. METHODS:66 rabbits were randomly divided into a normal group,a group with intact skin and a group with damaged skin. The latter two groups were respectively re-divided into PIB group,the groups of low,medium and high-dose PIB Gutong plaster and Gutong plaster group. An acute toxicity test was conducted on the rabbits,which 14 d of continuous observation was made 24 h af-ter transdermal administration. Another 60 rabbits were divided into several groups as above except for a normal group. A single pri-mary skin irritation test was conducted on them,where skin irritation reactions were recorded 6 h after a single administration based on intra-individual left/right self comparison method. 70 guinea pigs were randomized into a negative control group (vase-line),a PIB group,a positive control group(2,4-dinitrochlorobenzene),a Gutong plaster group and the groups of low,medium and high-dose PIB Gutong plaster,which were dosed for sensitization,followed by a skin sensitization test. RESULTS:No obvi-ous toxicity symptoms could be seen after administration of PIB Gutong plaster. The rabbits’intact or damaged skin had no irrita-tion response to PIB and low and medium-dose PIB Gutong plaster. PIB Gutong plaster caused no irritation response in the rabbits’ intact skin,but slight irritation in damaged skin 1 h after administration. The allergic reaction incidence of the positive control group of guinea pigs was 100% while that of any other groups was 0. CONCLUSIONS:The PIB Gutong plaster is safe for trans-dermal administration.

Sensibilización a ácaros domésticos en niños asmáticos severos / Sensitization to domestic mites identified in severe asthmatic patients

Introducción: las enfermedades alérgicas y el asma incrementan su prevalencia en Cuba y a nivel mundial. Los ácaros del polvo se encuentran entre los alérgenos perennes más prevalentes en todo el mundo. Objetivo: determinar la sensibilización a 3 especies de ácaros domésticos en los niños asmáticos severos de la Escuela Especial Celia Sánchez Manduley, de Tarará, provincia La Habana. Métodos: se realizó un estudio descriptivo transversal en 91 alumnos, durante el curso escolar 2011-2012, y a toda la muestra se le realizaron pruebas cutáneas por punción (prick test), utilizando extractos Vallergen-BT (Blomia tropicalis), Vallergen-DS (Dermatophagoides siboney) y Vallergen-DP (Dermatophagoides pteronyssinus) confeccionados por el Centro de Biopreparados, en Cuba; además se determinó IgE sérica total. Resultados: la rinitis alérgica resultó la comorbilidad alérgica más frecuente. El total de los pacientes presentó reactividad cutánea positiva a los ácaros, así como IgE sérica total elevada. La sensibilización frente al D. pteronyssinus se reportó en el 93,4 por ciento de los pacientes. No existió diferencia estadísticamente significativa en el diámetro del habón. Existió correlación entre la positividad de la IgE sérica total y la sensibilización cutánea a los 3 ácaros del polvo estudiado. Conclusiones: existe una estrecha relación entre el asma bronquial y la sensibilización a ácaros, con predominio de la especie D. Pteronyssinus

Introduction: the prevalence of allergic diseases and asthma grows in Cuba and worldwide. Dust mites are one of the most prevailing perennial allergens throughout the world. Objective: to determine the sensitization to 3 domestic mite species of severe asmathic children from Celia Sanchez Manduley special school located in Tarara, Havana province. Methods: a cross-sectional descriptive study was carried out in 91 students during the 2011-2012 academic year. The whole sample was performed prick tests using Vallergen-BT (Blomia tropicalis), Vallergen-DS (Dermatophagoides siboney) and Vallergen-DP (Dermatophagoides pteronyssinus) extracts prepared by the National Center of Biopreparations and their total serum IgE were additionally estimated. Results: allergic rhinitis proved to be the most frequent comorbidity. All the patients showed positive skin reactivity to mites as well as increased total serum IgE. Sensitization to D. pteronyssinus was reported in 93.4 percent of patients. There was no statistically significant difference in the habon diameter, but total serum IgE positivity and skin sensitization to the three dust mites under study were correlated. Conclusions: there is close association between bronchial asthma and sensitization to mites, being D. Pteronyssinus predominant

Skin Sensitization Study of Bee Venom (Apis mellifera L.) in Guinea Pigs

Bee venom (Apis mellifera L., BV) has been used as a cosmetic ingredient for antiaging, anti-inflammatory and antibacterial functions. The aim of this study was to access the skin sensitization of BV, a Buehler test was conducted fifty healthy male Hartley guinea pigs with three groups; Group G1 (BV-sensitization group, 20 animals), group G2 (the positive control-sensitization group, 20 animals), and group G3 (the ethyl alcohol-sensitization group, 10 animals). The exposure on the left flank for induction was repeated three times at intervals of one week. Two weeks after the last induction, the challenge was performed on the right flank. No treatment-related clinical signs or body weight changes were observed during the study period. The average skin reaction evaluated by erythema and edema on the challenge sites and sensitization rate in the BV-sensitization group at 30 hours were 0.0 and 0%, respectively, which are substantially low compared with in positive control group (average skin reaction: 0.55, sensitization rate: 40%) and identical with in vehicle control group, representing a weak sensitizing potential. The average skin reaction and sensitization rate observed at 54 hours were 0.0 and 0% in the BV-sensitization group, respectively, and 0.25 and 20% in the positive control group, respectively. It was concluded that BV classified to Grade I, induced no sensitization when tested in guinea pigs and may provide a developmental basis for a cosmetic ingredient or external application for topical uses.

Skin sensitization test of two new medical titanium alloys / 实用口腔医学杂志

Objective:To study the sensitization of two newly developed titanium alloys, TLE and TLM.Methods:According to ISO 10993-10:1995 standard,maximization test was conducted in guinea pig.The skin sensitization reactions,including erythema and oedema, induced by TLE, TLM, normal saline and 2,4-dinitrochlorobenzene were observed and scored respectively at 24,48 and 72 h exposure of the infusion of the materials. The allergenic rates and mean response score were calculated.Results:The allergenic rates and score of skin reaction of TLE and TLM were 0/15 and 0,those of normal saline 0/15 and 0,those of 2,4-dinitrochlo-robenzene 15/15 and 5,respectively.Conclusion: TLE and TLM both are not of sensitization.

Advance for Development of In Vitro Methods of Skin Sensitization Test / 环境与健康杂志

Due to a greater emphasis placed on non-animal test and our deeper understanding of allergic contact dermatitis,many researchers have tried several approaches in developing an in vitro skin sensitization test.The development of in vitro methods for predicting contact sensitization potential was reviewed in this paper,including cell-based methods,human skin equivalent/reconstituted epidermis cultures,peptide/protein reactivity,and quantitative structure-activity relationship.