We used in situ hybridization and immunohistochemistry to examine the expression and cellular provenance of TSLP, Th2-attracting (thymus and activation-regulated chemokine (TARC)/CCL17, macrophage-derived chemokine (MDC)/CCL22, I-309/CCL1) and Th1-attracting (IFN-gamma-inducible protein 10 (IP-10)/CXCL10, IFN-inducible T cell alpha-chemoattractant (I-TAC)/CXCL11) chemokines and expression of their receptors CCR4, CCR8, and CXCR3 in bronchial biopsies from 20 asthmatics and 15 normal controls.
Compelling evidence suggests that the epithelial cell-derived cytokine thymic stromal lymphopoietin (TSLP) may initiate asthma or atopic dermatitis through a dendritic cell-mediated T helper (Th)2 response.
Recently, thymic stromal lymphopoietin (TSLP) has been shown to play a key role in the development of T(H)2-type allergic inflammation in patients with asthma.
We selected 6 single nucleotide polymorphisms in thymic stromal lymphopoietin and genotyped 5565 individuals from 4 independent asthma studies and tested for association with asthma, atopy, atopic asthma, and airway hyperresponsiveness by using a general allelic likelihood ratio test.
Thymic stromal lymphopoietin (TSLP) is elevated in airway inflammatory diseases such as asthma and triggers dendritic cell-mediated activation of Th2 inflammatory responses.
This role is supported by the finding that TSLP expression is upregulated in keratinocytes of atopic dermatitis skin lesions and in bronchial epithelial cells in asthma.
BECs from subjects with asthma are biased towards higher TSLP and lower IFNbeta production in response to dsRNA, suggesting that viral infection in asthma may lead to an altered mediator profile that biases towards a Th2 immune response.
In addition, as our group recently found that TSLP variants are associated with asthma and reduced lung function, we assessed whether TSLP single nucleotide polymorphisms (SNPs) were associated with baseline lung function in non-COPD, nonasthmatic healthy subjects (n = 1368).
Associations with variation in genes encoding the epithelial cell-derived cytokines, interleukin-33 (IL-33) and thymic stromal lymphopoietin (TSLP), and the IL1RL1 gene encoding the IL-33 receptor, ST2, highlight the central roles for innate immune response pathways that promote the activation and differentiation of T-helper 2 cells in the pathogenesis of both asthma and allergic diseases.
Four were at previously reported loci on 17q21, near IL1RL1, TSLP and IL33, but we report for the first time, to our knowledge, that these loci are associated with asthma risk in three ethnic groups.
Four were at previously reported loci on 17q21, near IL1RL1, TSLP and IL33, but we report for the first time, to our knowledge, that these loci are associated with asthma risk in three ethnic groups.
Haplotype-specific score test indicated that an elevated risk for asthma was associated with a specific haplotype of TSLP involving SNP rs1898671 (OR = 1.58, 95% CI: 1.10-2.27, p = 0.01).
Overall, TSLP protein expression was significantly increased in airway epithelium and lamina propria of asthmatic patients, particularly in patients with severe asthma.
To analyze the polymorphism of the two SNPs Rs2289276 and Rs2289278 in TSLP gene and to evaluate the association between the two SNPs and asthma susceptibility in Chinese Han population by using case-control study.