This study provides the first evidence of global Treg impairment in IPF that strongly correlates with disease severity, suggesting a role for Tregs in the fibrotic process.

CD4 þ CD25 þ FOXP3 þ T regulatory cells (T regs ) prevent autoimmunity by restricting overexuberant immune responses, but the same subpopulation can incur detrimental effects on antitumor responses. In both cases, the suppressor potential of T regs appears to be strongly influenced by their compartmentalization. In myelodysplastic syndromes (MDS), immune deregulation and autoimmunity in the early stages might lead to ineffective hematopoiesis and bone marrow (BM) failure, whereas late-stage disease is characterized by the immune escape of the malignant clone. We show that these two stages of MDS are associated with differential T reg activity. Specifically, we found that in early stage MDS, compared with normal hematopoiesis and late stage MDS, T regs are dysfunctional and their BM homing through the CXCL12/CXCR4 axis is seriously impaired as a result of CXCR4 downregulation. Conversely, in late stage MDS, T regs are systemically and locally expanded and retain their function and migratory capacity. Moreover, T reg levels follow the disease course and are significantly reduced in treatment responding patients. Our findings indicate T reg involvement in the pathophysiology of MDS; defective suppressor function and BM trafficking of T regs may be important in the autoimmune process of early MDS, but increased T reg activity could favor leukemic clone progression in late stage disease.

No abstract

Immunophenotyping is indispensable in the differential diagnosis of B-cell chronic lymphoproliferative disorders (B-CLPDs). However, B-CLPDs often show overlapping immunophenotypic profiles and may be diagnostically challenging. CD1d is an HLA class I-like molecule that presents glycolipids to invariant natural killer T cells. Normal mature B cells constitutively express CD1d, but with the exception of some conflicting data, its expression in B-CLPDs is unknown. We demonstrate that in 222 B-CLPD cases, CD1d expression of less than 45% is strongly predictive of CLL (likelihood ratio, 32.3; specificity, 97.4%; sensitivity, 84.1%). In addition, CD1d showed significantly higher staining intensity in splenic marginal zone lymphoma compared with atypical hairy cell leukemia, lymphoplasmacytic lymphoma, and mantle cell lymphoma, thus allowing the discrimination of the former from the latter immunophenotypically overlapping B-CLPDs. It is important to note that in a given patient, CD1d expression on malignant B cells was similar between tissues and remained unaffected by disease stage and treatment status. Our findings strongly argue for the incorporation of CD1d into routine lymphoma panels.

Identification and molecular characterization of the --CAMPANIA deletion, a novel a8-thalassemic defect, in two unrelated Italian families