Mediterranean chromosome number reports - 23

This is the twenty-three of a series of reports of chromosomes numbers from Mediterranean area, peri-Alpine communities and the Atlantic Islands, in English or French language. It comprises contributions on 56 taxa: Anthriscus, Bupleurum, Dichoropetalum, Eryngium, Ferula, Ferulago, Lagoecia, Oenanthe, Prangos, Scaligeria, Seseli and Torilis from Turkey by Ju. V. Shner, T. V. Alexeeva, M. G. Pimenov & E. V. Kljuykov (Nos 1768-1783); Astrantia, Bupleurum, Daucus, Dichoropetalum, Eryngium, Heracleum, Laserpitium, Melanoselinum, Oreoselinum, Pimpinella, Pteroselinum and Ridolfia from Former Jugoslavia (Slovenia), Morocco and Portugal by J. Shner & M. Pimenov (1784-1798); Arum, Biarum and Eminium from Turkey by E. Akalin, S. Demirci & E. Kaya (1799-1804); Colchicum from Turkey by G. E. Genç, N. Özhatay & E. Kaya (1805-1808); Crocus and Galanthus from Turkey by S. Yüzbaşioglu, S. Demirci & E. Kaya (1809-1812); Pilosella from Italy by E. Di Gristina, G. Domina & A. Geraci (1813-1814); Narcissus from Sicily by A. Troia, A. M. Orlando & R. M. Baldini (1815-1816); Allium, Cerastium, Cochicum, Fritillaria, Narcissus and Thymus from Greece, Kepfallinia by S. Samaropoulou, P. Bareka & G. Kamari (1817-1823)

Prospective tracking of donor-reactive T-cell clones in the circulation and rejecting human kidney allografts

BACKGROUND: Antigen recognition of allo-peptides and HLA molecules leads to the activation of donor-reactive T-cells following transplantation, potentially causing T-cell-mediated rejection (TCMR). Sequencing of the T-cell receptor (TCR) repertoire can be used to track the donor-reactive repertoire in blood and tissue of patients after kidney transplantation. METHODS/DESIGN: In this prospective cohort study, 117 non-sensitized kidney transplant recipients with anti-CD25 induction were included. Peripheral mononuclear cells (PBMCs) were sampled pre-transplant and at the time of protocol or indication biopsies together with graft tissue. Next-generation sequencing (NGS) of the CDR3 region of the TCRbeta chain was performed after donor stimulation in mixed lymphocyte reactions to define the donor-reactive TCR repertoire. Blood and tissue of six patients experiencing a TCMR and six patients without rejection on protocol biopsies were interrogated for these TCRs. To elucidate common features of T-cell clonotypes, a network analysis of the TCR repertoires was performed. RESULTS: After transplantation, the frequency of circulating donor-reactive CD4 T-cells increased significantly from 0.86 ± 0.40% to 2.06 ± 0.40% of all CD4 cells (p < 0.001, mean dif.: -1.197, CI: -1.802, -0.593). The number of circulating donor-reactive CD4 clonotypes increased from 0.72 ± 0.33% to 1.89 ± 0.33% (p < 0.001, mean dif.: -1.168, CI: -1.724, -0.612). No difference in the percentage of donor-reactive T-cells in the circulation at transplant biopsy was found between subjects experiencing a TCMR and the control group [p = 0.64 (CD4(+)), p = 0.52 (CD8(+))]. Graft-infiltrating T-cells showed an up to six-fold increase of donor-reactive T-cell clonotypes compared to the blood at the same time (3.7 vs. 0.6% and 2.4 vs. 1.5%), but the infiltrating TCR repertoire was not reflected by the composition of the circulating TCR repertoire despite some overlap. Network analysis showed a distinct segregation of the donor-reactive repertoire with higher modularity than the overall TCR repertoire in the blood. These findings indicate an unchoreographed process of diverse T-cell clones directed against numerous non-self antigens found in the allograft. CONCLUSION: Donor-reactive T-cells are enriched in the kidney allograft during a TCMR episode, and dominant tissue clones are also found in the blood