Transient monoclonal expansion of CD8+/CD57+ T‐cell large granular lymphocytes after primary cytomegalovirus infection

Abstract

Lymphocytosis associated with viral infection is generally polyclonal or oligoclonal. In this article, we describe a case of transient monoclonal CD81/CD571 T-cell lymphocytosis with large granular lymphocyte (LGL) morphology occurring after primary CMV infection and review cases of virus-associated monoclonal CD81 T-cell expansions reported in the literature. Several clinical features shared by virus-associated monoclonal CD81 T-cell expansions suggest the reactive nature of the lymphocytosis. Based on this, our case report and those reported in the literature support the notion that T-cell receptor clonality per se is not necessarily indicative of malignancy. These observations further corroborate the need for a close follow-up before assigning the diagnosis of LGL leukemia to individuals developing monoclonal CD81 T-cell expansions. Am. J. Hematol. 82:1103Hematol. 82: -1105Hematol. 82: , 2007

NKG2A inhibits NKG2C effector functions of γδ T cells: implications in health and disease

“…Cytotoxicity assays 51 Cr release-redirected killing assay was performed as described previously [36] using the murine FcR ϩ P815 mastocytoma cell line as target cells in the presence of anti-MHC I, -NKG2C, or -CD16 (B73.1, kindly provided by Dr. G. Trinchieri, Schering Plough) or anti-NKG2D mAb. Maximal and spontaneous release was determined by incubating 51 Cr-labeled target cells with 1 M HCl or medium alone, respectively.…”

“…Maximal and spontaneous release was determined by incubating 51 Cr-labeled target cells with 1 M HCl or medium alone, respectively. In another set of experiments, the 721.221 HLA class I-deficient lymphoblastoma cell line, transfected with a chimeric HLA-B58 construct carrying a HLA-G leader sequence leading to HLA-E surface expression, DT360 (kindly provided by Dr. Kalle Soderstrom, Stanford University, Palo Alto, CA, USA), was used as a target cell for the cytotoxicity assay, as described previously [37].…”

“…Although these donors have not been tested for HCMV positivity, the concordant, increased NKG2C expression on all lymphocyte subsets strongly points to an involvement of HCMV infection on the induction of NKG2Cϩ ␥␦ T cells. Moreover, it has been shown that CMV infection determines monoclonal expansion of T LDGL [51], and common infections, such as CMV and EBV, have been associated with ␣␤ and NK LDGL [52,53].…”

Large granular lymphocytosis and its impact on long-term clinical outcomes following allo-SCT

“…This is consistent with the suggestion by Mohty et al 5 that LGL lymphocytosis may emerge generally in the context of chronic Ag stimulation associated with GVHD in allograft recipients as well as recurrent CMV infections, or other chronic Ag stimulations after autologous or allogeneic hematopoietic SCT. There is evidence that primary CMV infections may activate monoclonal LGL expansion, [21][22][23] with persistence even after successful resolution of the CMV infection. 23 After allogeneic hematopoietic SCT, CMV reactivation may trigger activation of LGL expansion so that these LGL cells persist even after controlling for CMV reactivation.…”

Advances in diagnosis and treatment of large granular lymphocyte syndrome

“…They include viral infections (e.g. human immunodeficiency virus and cytomegalovirus) as well as autoimmune diseases and represent immune response against viral antigens or autoantigens [31][32][33]. Felty's syndrome, a clinical triad with rheumatoid arthritis, neutropenia, and variable splenomegaly, is associated with a clonal spectrum of T-LGL proliferations [34].…”