title: Sequential monitoring of lymphocyte subsets and of T-and-B cell neogenesis indexes to identify time-varying immunologic profiles in relation to graft-versus-host disease and relapse after allogeneic stem cell transplantation.
abstract: T and B lymphocyte subsets have been not univocally associated to Graft-versus-host disease (GVHD) and relapse of hematological malignancies after stem cell transplantation (SCT). Their sequential assessment together with B and T cell neogenesis indexes has been not thoroughly analysed in relation to these changing and interrelated immunologic/clinic events yet. Lymphocyte subsets in peripheral blood (PB) and B and T cell neogenesis indexes were analysed together at different time points in a prospective study of 50 patients. Principal component analysis (PCA) was used as first step of multivariate analysis to address issues related to a high number of variables versus a relatively low number of patients. Multivariate analysis was completed by Fine-Gray proportional hazard regression model. PCA identified 3 clusters of variables (PC1-3), which correlated with acute GVHD: PC1 (pre-SCT: KRECs≥6608/ml, unswitched memory B <2.4%, CD4+TCM cells <45%; HR 0.5, p = 0.001); PC2 (at aGVHD onset: CD4+>44%, CD8+TCM cells>4%; HR 1.9, p = 0.01), and PC3 (at aGVHD onset: CD4+TEMRA<1, total Treg<4, TregEM <2 cells/μl; HR 0.5, p = 0.002). Chronic GVHD was associated with one PC (TregEM <2 cells/μl at day+28, CD8+TEMRA<43% at day+90, immature B cells<6 cells/μl and KRECs<11710/ml at day+180; HR 0.4, P = 0.001). Two PC correlated with relapse: PC1 (pre-SCT: CD4+ <269, CD4+TCM <120, total Treg <18, TregCM <8 cells/μl; HR 4.0, p = 0.02); PC2 (pre-SCT mature CD19+ >69%, switched memory CD19+ = 0 cells and KRECs<6614/ml at +90; HR 0.1, p = 0.008). All these immunologic parameters were independent indicators of chronic GVHD and relapse, also considering the possible effect of previous steroid-therapy for acute GVHD. Specific time-varying immunologic profiles were associated to GVHD and relapse. Pre-SCT host immune-microenvironment and changes of B cell homeostasis could influence GVH- and Graft-versus-Tumor reactions. The paradoxical increase of EM Treg in PB of patients with GVHD could be explained by their compartmentalization outside lymphoid tissues, which are of critical relevance for regulation of GVH reactions.
authors.affiliation: Chair of Haematology, Stem Cell Transplantation Unit, University of Brescia, Brescia, Italy.
authors.forename: Cristina
authors.initials: C
authors.lastname: Skert
authors.affiliation: Centro Ricerca Emato-oncologica AIL (CREA), Spedali Civili of Brescia, Brescia, Italy.
authors.forename: Simone
authors.initials: S
authors.lastname: Perucca
authors.affiliation: Centro Ricerca Emato-oncologica AIL (CREA), Spedali Civili of Brescia, Brescia, Italy.
authors.forename: Marco
authors.initials: M
authors.lastname: Chiarini
authors.affiliation: Centro Ricerca Emato-oncologica AIL (CREA), Spedali Civili of Brescia, Brescia, Italy.
authors.forename: Viviana
authors.initials: V
authors.lastname: Giustini
authors.affiliation: Centro Ricerca Emato-oncologica AIL (CREA), Spedali Civili of Brescia, Brescia, Italy.
authors.forename: Alessandra
authors.initials: A
authors.lastname: Sottini
authors.affiliation: Centro Ricerca Emato-oncologica AIL (CREA), Spedali Civili of Brescia, Brescia, Italy.
authors.forename: Claudia
authors.initials: C
authors.lastname: Ghidini
authors.affiliation: Department of Life Sciences, Research Unit of Biodiversity Informatics, University of Trieste, Trieste, Italy.
authors.forename: Stefano
authors.initials: S
authors.lastname: Martellos
authors.affiliation: Chair of Haematology, Stem Cell Transplantation Unit, University of Brescia, Brescia, Italy.
authors.forename: Federica
authors.initials: F
authors.lastname: Cattina
authors.affiliation: Chair of Haematology, Stem Cell Transplantation Unit, University of Brescia, Brescia, Italy.
authors.forename: Benedetta
authors.initials: B
authors.lastname: Rambaldi
authors.affiliation: Chair of Haematology, Stem Cell Transplantation Unit, University of Brescia, Brescia, Italy.
authors.forename: Valeria
authors.initials: V
authors.lastname: Cancelli
authors.affiliation: Chair of Haematology, Stem Cell Transplantation Unit, University of Brescia, Brescia, Italy.
authors.forename: Michele
authors.initials: M
authors.lastname: Malagola
authors.affiliation: Chair of Haematology, Stem Cell Transplantation Unit, University of Brescia, Brescia, Italy.
authors.forename: Alessandro
authors.initials: A
authors.lastname: Turra
authors.affiliation: Chair of Haematology, Stem Cell Transplantation Unit, University of Brescia, Brescia, Italy.
authors.forename: Nicola
authors.initials: N
authors.lastname: Polverelli
authors.affiliation: Centro Ricerca Emato-oncologica AIL (CREA), Spedali Civili of Brescia, Brescia, Italy.
authors.forename: Simona
authors.initials: S
authors.lastname: Bernardi
authors.affiliation: Centro Ricerca Emato-oncologica AIL (CREA), Spedali Civili of Brescia, Brescia, Italy.
authors.forename: Luisa
authors.initials: L
authors.lastname: Imberti
authors.affiliation: Chair of Haematology, Stem Cell Transplantation Unit, University of Brescia, Brescia, Italy.
authors.forename: Domenico
authors.initials: D
authors.lastname: Russo
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D001402:B-Lymphocytes / Q000166:cytology*; D005260:Female; D005434:Flow Cytometry; D006086:Graft vs Host Disease / Q000276:immunology*; D018380:Hematopoietic Stem Cell Transplantation; D006801:Humans; D016131:Lymphocyte Subsets; D008297:Male; D008875:Middle Aged; D012008:Recurrence; D013601:T-Lymphocytes / Q000166:cytology*; D014184:Transplantation, Homologous; D055815:Young Adult