@article {717, title = {Developmental heterogeneity in DNA packaging patterns influences T-cell activation and transmigration.}, journal = {PLoS One}, volume = {7}, year = {2012}, month = {2012}, pages = {e43718}, abstract = {

Cellular differentiation programs are accompanied by large-scale changes in nuclear organization and gene expression. In this context, accompanying transitions in chromatin assembly that facilitates changes in gene expression and cell behavior in a developmental system are poorly understood. Here, we address this gap and map structural changes in chromatin organization during murine T-cell development, to describe an unusual heterogeneity in chromatin organization and associated functional correlates in T-cell lineage. Confocal imaging of DNA assembly in cells isolated from bone marrow, thymus and spleen reveal the emergence of heterogeneous patterns in DNA organization in mature T-cells following their exit from the thymus. The central DNA pattern dominated in immature precursor cells in the thymus whereas both central and peripheral DNA patterns were observed in na{\"\i}ve and memory cells in circulation. Na{\"\i}ve T-cells with central DNA patterns exhibited higher mechanical pliability in response to compressive loads in vitro and transmigration assays in vivo, and demonstrated accelerated expression of activation-induced marker CD69. T-cell activation was characterized by marked redistribution of DNA assembly to a central DNA pattern and increased nuclear size. Notably, heterogeneity in DNA patterns recovered in cells induced into quiescence in culture, suggesting an internal regulatory mechanism for chromatin reorganization. Taken together, our results uncover an important component of plasticity in nuclear organization, reflected in chromatin assembly, during T-cell development, differentiation and transmigration.

}, keywords = {Animals, Antigens, CD, Antigens, Differentiation, T-Lymphocyte, Bone Marrow Cells, Cell Lineage, Cell Movement, Cell Nucleus, Chromatin, DNA, Hematopoietic Stem Cells, Lectins, C-Type, Lymphocyte Activation, Mice, Microscopy, Confocal, Models, Biological, Models, Statistical, Sequence Analysis, DNA, Spleen, T-Lymphocytes}, issn = {1932-6203}, doi = {10.1371/journal.pone.0043718}, author = {Gupta, Soumya and Marcel, Nimi and Talwar, Shefali and Garg, Megha and R, Indulaxmi and Perumalsamy, Lakshmi R and Sarin, Apurva and Shivashankar, G V} } @article {719, title = {Functional tumor infiltrating TH1 and TH2 effectors in large early-stage cervical cancer are suppressed by regulatory T cells.}, journal = {Int J Gynecol Cancer}, volume = {22}, year = {2012}, month = {2012 Sep}, pages = {1130-7}, abstract = {

OBJECTIVE: Analysis of tumor-infiltrating lymphocytes (TILs) is one of the cornerstones for the understanding of immune responses prevailing in the tumor microenvironment. We studied TILs from squamous cell carcinoma of the cervix ex vivo without proliferating them in vitro before analysis.

METHODS: Whereas TILs were magnetic activated cell separation enriched and flow sorted into CD4 CD25 (regulatory T cells [Tregs]), CD4 CD25 (effector T cells [Teffs]) were directly purified by flow cytometry, and both these subsets were characterized phenotypically and functionally. Tissue sections were probed for interleukin 4 (IL-4) and interferon γ.

RESULTS: Effector T cells constitutively expressed both interferon γ and IL-4 prototypical cytokines of TH1 and TH2, respectively, and were able to proliferate and secrete higher quantities of both cytokines in response to anti-CD3/anti-CD28 and autologous tumor lysates. Only 53\% of cervical cancer Tregs were FOXP3, elaborated transforming growth factor β1, and IL-10 and were able to inhibit both T helper subsets.

CONCLUSIONS: Intratumoral Teffs represented functionally active subsets of both TH1 and TH2 that were not anergic but were suppressed by multiple Treg subsets, which comprised FOXP3 + Tregs and Tregs secreting transforming growth factor β1 and IL-10. These results imply that the microenvironment of cervical carcinomas harbored both TH1 and TH2 subsets of CD4 Teffs that were functionally active but were perhaps unable to perform because of the overpowering effect of Tregs.

}, keywords = {Carcinoma, Squamous Cell, Cytokines, Female, Flow Cytometry, Humans, Immune Tolerance, Interferon-gamma, Lymphocyte Activation, Lymphocytes, Tumor-Infiltrating, Neoplasm Staging, T-Lymphocytes, Regulatory, Th1 Cells, Th2 Cells, Uterine Cervical Neoplasms}, issn = {1525-1438}, doi = {10.1097/IGC.0b013e318262aa53}, author = {Adurthi, Sreenivas and Mukherjee, Geetashree and Krishnamurthy, H and Sudhir, Krishna and Bafna, Uttamchand D and Umadevi, Kswamy and Jayshree, Rudrapatna Subramanyam} }