02946nas a2200373   4500000000100000008004100001260000900042653001000051653003100061653001400092653003800106653001100144653001900155653003000174653001100204653001200215653002300227653000900250653001600259653004000275653005200315653001500367653001600382100001200398700001300410700001100423245012400434856007700558300001000635490000600645050001500651520189200666022001402558       2013                            d  c201310aAdult10aCD4-Positive T-Lymphocytes10aCytokines10aEnzyme-Linked Immunosorbent Assay10aFemale10aFlow Cytometry10aGene Expression Profiling10aHumans10aleprosy10aLymphocyte Subsets10aMale10aMiddle Aged10aReal-Time Polymerase Chain Reaction10aReverse Transcriptase Polymerase Chain Reaction10aTh17 Cells10aYoung Adult1 aSaini C1 aRamesh V1 aNath I00aCD4+ Th17 cells discriminate clinical types and constitute a third subset of non Th1, Non Th2 T cells in human leprosy.  uhttp://www.ncbi.nlm.nih.gov/pmc/articles/PMC3723566/pdf/pntd.0002338.pdf  ae23380 v7  aSAINI 20133 a<p><b>BACKGROUND: </b>Patients with localized tuberculoid and generalized lepromatous leprosy show respectively Th1 and Th2 cytokine profile. Additionally, other patients in both types of leprosy also show a non discriminating Th0 cytokine profile with both interferon-γ and IL-4. The present study investigated the role of Th17 cells which appear to be a distinct subtype of Th subtypes in 19 tuberculoid and 18 lepromatous leprosy patients. Five healthy subjects with long term exposure to infection and 4 skin biopsies from healthy subjects undergoing cosmetic surgery were used as controls.</p><p><b>METHODOLOGY/PRINCIPLE FINDINGS: </b>An array of Th17 related primers for cytokines, chemokines and transcription factors was used in real time reverse transcribed PCR to evaluate gene expression, ELISA for cytokine secretion in the supernatants of antigen stimulated PBMC cultures and flow cytometry for establishing the phenotype of the IL-17, IL-21 producing cells.</p><p><b>CONCLUSIONS/SIGNIFICANCE: </b>IL-17 isoforms showed significantly higher expression and release in supernatants of antigen stimulated PBMC cultures and dermal lesions of healthy contacts and tuberculoid leprosy as compared to lepromatous leprosy (p<0.003). This was further confirmed by Th17 associated transcription factor RORC, cytokines IL-21, IL-22, and IL-23, chemokines MMP13, CCL20, CCL22. Of interest was the association of IL-23R and not IL-6R with IL-17(+) cells. The Th17 cells were CD4(+) CCR6(+) confirming their effector cell lineage. Polarized Th1 cytokines were seen in 3/7 tuberculoid and Th2 cytokines in 5/10 lepromatous leprosy patients. Of importance was the higher association of Th17 pathway factors with the non-polarized Th0 types as compared to the polarized Th1 and Th2 (p<0.01). Our study draws attention to a third type of effector Th cell that may play a role in leprosy.</p>  a1935-2735