Human memory and naive CD4 T cells can mainly be identified by the reciprocal expression of the CD45RO or CD45RA isoforms. In HIV-1 infection, blood CD45RO memory CD4 T cells are preferentially infected and serve as a major viral reservoir. The molecular mechanism dictating this differential susceptibility to HIV-1 remains largely obscure. Here, we report that the different susceptibility of me...

The transcription factor forkhead box P3 (FOXP3) is involved in immune cell regulation, and carcinoembryonic antigen-related cell adhesion molecule 6 (CEACAM6) is an adhesion molecule of the immunoglobulin superfamily. These two genes are associated with cancer progression. In the current study, colon tissue specimens from 78 cases of colon cancer (including 40 of stage I-II and 38 of stage III...

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...

Glucocorticoids (GC) are used as the first-line treatment of immune thrombocytopenia (ITP), but 10-20% patients insensitive to them. Regulatory T cells (Tregs) can maintain tolerance in autoimmune diseases. The present research pooled 55 with newly diagnosed ITP and 44 healthy volunteers from seven hospitals. All received GC were divided into GC-sensitive GC-insensitive groups according curativ...

A total of 106 patients, included in the study, were divided into three groups with regard to Helicobacter pylori infection. Endoscopy and histopathological examination of the stomach, based on the Sydney's System, were performed in all the children. CD45RA and CD45RO cells were identified by means of specific antibodies in the inflammatory infiltrate of the antral mucosa. An increased expressi...

Immune response to ultraviolet radiation-modified skin antigens has been suggested as a pathomechanism of skin lesions in discoid lupus erythematosus and polymorphous light eruption. In order to elucidate the role of T-lymphocyte subsets in this response, we studied the distribution of CD45RO+, CD45RA+ and CD31+ cells and the endothelial expression of adhesion molecules E-selectin/P-selectin, i...

Differences in levels of specific enzymes utilized in intracellular signalling could be a factor in the distinct signalling properties observed in memory and naive T cells. We have studied the expression of both classical and non-classical protein kinase of C (PKC) isoenzymes in CD45RA and CD45RO cells using a combination of Western blot and flow cytometric analysis. These data indicate that CD...

INTRODUCTION HIV causes defects in memory B cells in children, but the mechanisms of those defects have not been fully elucidated. One possible mechanism is the lack of T-cell help to B cells during immune reactions. However, few studies have assessed the effect of HIV on follicular helper T cells (TFH cells) in children. METHODS In this study, follicular-homing CD4 T cells and memory B cells...

BACKGROUND In humans it has been reported that a major site of the latent reservoir of HIV is within CD4+ T cells expressing the memory marker CD45RO, defined by the mAb UCHL1. There are conflicting reports regarding the expression of this antigen in macaques, the most relevant animal species for studying HIV pathogenesis and testing new therapies. There is now a major effort to eradicate HIV r...

Memory T cells display phenotypic heterogeneity. Surface antigens previously regarded as exclusive markers of naive T cells, such as L-selectin (CD62L), can also be detected on some memory T cells. Moreover, a fraction of CD45RO+ (positive for the short human isoform of CD45) memory T cells reverts to the CD45RA+ (positive for the long human isoform of CD45) phenotype. We analyzed patients with...