T cell lymphopenia results in peripheral homeostatic expansion to maintain the T cell immune system, which is termed lymphopenia-induced proliferation (LIP). LIP is a potential risk for expanding autoreactive clones to become pathogenic in human and murine autoimmune diseases. However, the ontogeny of T cells that induce autoantibody production by autoreactive B cells in LIP remains unclear. Tr...

OBJECTIVES To evaluate the haematological findings of patients with severe acute respiratory syndrome (SARS). DESIGN Analysis of the demographic, clinical, and laboratory characteristics of patients with SARS. SETTING Prince of Wales Hospital, Hong Kong. Subjects All patients with a diagnosis of SARS between 11 March and 29 March 2003 who had no pre-existing haematological disorders. MAIN...

Rheumatoid arthritis develops in association with a defect in peripheral CD4(+) T cell homeostasis. T cell lymphopenia has also been shown to be a barrier to CD4(+) T cell clonal anergy induction. We therefore explored the relationship between clonal anergy induction and the avoidance of autoimmune arthritis by tracking the fate of glucose-6-phosphate isomerase (GPI)-reactive CD4(+) T cells in ...

Lymphopenia induces T cells to undergo cell divisions as part of a homeostatic response mechanism. The clonal response to lymphopenia is extremely diverse, and it is unknown whether this heterogeneity represents distinct mechanisms of cell-cycle control or whether a common mechanism can account for the diversity. We addressed this question by combining in vivo and mathematical modeling of lymph...

BACKGROUND Nosocomial infection remains an important health problem in long stay (> 3 days) pediatric intensive care unit (PICU) patients. Admission risk factors related to the development of nosocomial infection in long stay immune competent patients in particular are not known. METHODS Post-hoc analysis of the previously published Critical Illness Stress induced Immune Suppression (CRISIS) ...

The immunomodulator fingolimod (FTY720) induces lymphopenia by inhibiting lymphocyte egress from thymus and secondary lymphoid organs (SLOs). It is phosphorylated mainly by sphingosine kinase (SK) 2 in vivo. FTY720-phosphate (FTY-P) activated and rapidly internalized S1P(1), which is the major sphingosine 1-phosphate (S1P) receptor for mediating lymphocyte egress. Although FTY-P is thought to b...

To cite: Ravaglia C, Gurioli C, Casoni GL, et al. Thorax 2013;68:496–497. CLINICAL PRESENTATION A 42-year-old woman was referred to our department with a 5 months history of intermittent fever and fatigue. Her past medical history included a consolidated diagnosis of sarcoidosis (obtained 7 years before with a sub-carinal lymph node biopsy) and in the previous years she had been treated with st...

Plasma cortisol levels were determined in 51 children on admission to hospital for a variety of acute illnesses which were associated with a lymphopenia, and again when the lymphocyte count had returned to normal. The ratio cortisol level/lymphocyte count was much higher in the acute phase of the illness than later when the lymphocyte count had returned to normal. It is concluded that the lymph...

Abstract Background Pneumocystis jirovecii pneumonia (PCP) is a potentially deadly infection afflicting the immunocompromised population, including solid organ transplant recipients. Several risk factors have been described, acute rejection, lymphopenia, and cytomegalovirus (CMV) infection. However, little known regarding imparted by posttransplant lymphoproliferative disorder (PTLD). Methods W...

BACKGROUND During the spring of 2009, a pandemic influenza A (H1N1) virus emerged and spread globally. We describe the clinical characteristics and factors associated with the death of patients who were hospitalized with 2009 H1N1 influenza pneumonia in Shenyang, China, from November to December 2009. METHODS We carried out a retrospective chart review of 68 patients who were hospitalized wit...