TARC ( thymus and activation-regulated chemokine )

TARC (thymus and activation-regulated chemokine) is a chemokine that induces chemotaxis in leukocytes. During atopic dermatitis TARC is produced by the affected epidermal keratinocytes and migrates lymphocytes (CCR4-expressing Th2 cells) locally. During the Th2-dominant immune response, IgE production and eosinophil infiltration and activationare thought to be induced to causethe allergic response. In the treatment of atopic dermatitis, accuracy in understanding the severity of the disease presentation is imperative for making a considered choice in terms of efficacy of topical steroids, etc. depending on the severity. As a test indicative of the presentation of atopic dermatitis, blood serum TARC levels have been shown to increase by relatively a large amount to changes in the severity of the disease compared to the previous tests. TARC analysis can be of clinical assistance in the evaluation of disease severity for drug choice or change, in addition to the main evaluation of the dermatological signs in patients diagnosed with atopic dermatitis.

Blood serum TARC levels and severity of atopic dermatitis:
Significant differences in blood serum TARC levels are seen between healthy individuals, and people with mild, moderate and severe atopic dermatitis, with increasing levels of TARC observed with increasing severity of disease. (Figure 1)

StandardReferenceRange:

Children (6 -12 months)	：Below 1367 pg/mL
Children (1-2 years)	：Below 998 pg/mL
Children (over 2 years)	：Below 743 pg/mL
Adults	：Below 450 pg/mL

　
Criteria for assessment of severity* of atopic dermatitis:

	Blood Serum TARC Level	Criteria of Severity of Atopic Dermatitis
Adult	below 700pg/mL	mild
	from 700pg/mL	moderate to severe
Infant (over 2 years)	below 760pg/mL	mild
	from 760pg/mL	moderate to severe

Statistically significant cut-off values could not be established for children under 2 years due to lack of data.

*Severity 　
Severity of disease in adults was assessed using SCORAD, and divided into three levels of severity based on the degree and size of the area of rash; mild (less than 15 points), moderate (between 15 and 40 points), severe (above 40 points).

Reference texts
Fujisawa Takao et al.: Japanese Journal of Pediatric Allergy and Clinical Immunology，19(5),744(2005)
Tamaki Kunihiko et al.: Japanese Journal of Dermatology，116(1),,27(2006)
Nakamura Kouichiro: Allergy and Immunology，13(1),54(2006)
Imai T. et al. :J Biol Chem.,271,21514(1996)
Kakinuma T. et al.:J Allergy Clin Immunol., 107,535(2001)

Cited from attacheddocuments from the manufacturer.


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The party requiring contract analysis services contacts the KM Assay Center by phone or electronic mail.
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