Seventeen volunteers received an intravenous bolus of endotoxin (2 ng/kg of body weight). Endotoxin-induced lymphopenia was constituted mainly by cells with an immature phenotype (CD45RA(+) CD45RO(-)) that were less likely to undergo apoptosis (CD28(+)), whereas cells with the highest rates of disappearance were characterized by an activated phenotype (CD45RA(-) CD45RO(+)) as well as a phenotyp...

OBJECTIVE To characterize prognostic parameters for systemic lupus erythematosus (SLE) flares. METHODS In a prospective study, 120 SLE patients attending our out-patient clinic were evaluated every 3 months for 2 yr. At every visit clinical manifestations and laboratory parameters were assessed and the SLE disease activity index (SLEDAI) was determined. A correlation analysis of the number of...

Diabetes-prone (DP) BB rats spontaneously develop insulin-dependent diabetes resembling type 1 diabetes mellitus in man. They also exhibit lifelong T cell deficiency. The segregation of both diabetes and lymphopenia was studied in crosses between this inbred line of rats and the related but nondiabetic and nonlymphopenic inbred diabetes-resistant (DR) BB rat line. Diabetes segregated as a singl...

A single point mutation in a novel immune-associated nucleotide gene 5 (Ian5) coincides with severe T cell lymphopenia in BB rats. We used a transgenic rescue approach in lymphopenic BB-derived congenic F344.lyp/lyp rats to determine whether this mutation is responsible for lymphopenia and to establish the functional importance of this novel gene. A 150-kb P1 artificial chromosome (PAC) transge...

During illness and stress, the immune system can suffer a considerable loss of T cells (lymphopenia). The remaining T cells undergo vigorous compensatory expansion, known as homeostatic proliferation, to reconstitute the immune system. Interestingly, human diseases of autoimmune etiology often present with immune deficiencies such as lymphopenia. In this study, we show that reduced T cell numbe...

The sphingosine 1-phosphate receptor 1 (S1P(1)) promotes lymphocyte egress from lymphoid organs. Previous work showed that agonist-induced internalization of this G protein-coupled receptor correlates with inhibition of lymphocyte egress and results in lymphopenia. However, it is unclear if S1P(1) internalization is necessary for this effect. We characterize a knockin mouse (S1p1r(S5A/S5A)) in ...

PURPOSE Radiotherapy can result in lymphopenia, which has been linked to poorer survival. Here, we test the hypothesis that radiotherapy-induced lymphopenia is mediated by a tumor-secreted factor, Galectin-1 (Gal-1), which possesses T-cell proapoptotic activities. EXPERIMENTAL DESIGN Matched Gal-1 wild-type (WT) or null mice were implanted with Lewis lung carcinoma (LLC-1) that either express...

Lymphopenia and lymphoid depletion occur in adults dying of sepsis. Prolactin increases Bcl-2 expression, suppresses stress-induced lymphocyte apoptosis, and improves survival from experimental sepsis. We hypothesized that prolonged lymphopenia, lymphoid depletion, and hypoprolactinemia occur in children dying with sepsis and multiple organ failure (MOF). Fifty-eight critically ill children wit...