OBJECTIVE Cytokine induced killer (CIK) cells are ex-vivo expanded T cells endowed with both T and Natural Killer cell properties. The standard protocol for generation of CIK cells is to culture peripheral blood mononuclear cells (PBMC) in the presence of interferon- gamma (IFN-γ), monoclonal antibody (mAb) against CD3 and interleukin-2 (IL-2). However, this protocol lacks costimulatory signal ...

Although it is generally recognized that the function of the immune system declines with age, the nature of the underlying defects is still poorly understood. We now demonstrate the predominance of CD8(+)CD28(-) T cell clonal expansions in elderly persons who fail to produce specific Abs following influenza vaccination. These clones express effector cell markers and are mostly CD45RA(+). When i...

Measles remains an important problem in Africa, where human immunodeficiency virus type 1 (HIV-1) infection is prevalent. To identify the consequences of coinfection, Zambian children hospitalized with measles were studied at entry, discharge, and 1 month after discharge. All children had low lymphocyte and eosinophil counts at entry and high leukocyte and monocyte counts during recovery. The d...

Abstract Background and Aims Immunosenescence, as a consequence of ageing or chronic inflammation, encompasses spectrum lymphocyte characteristics, including the presence absence certain surface molecules. Aim present study was to evaluate immunosenescent effect two different forms Systemic Lupus Erythematosus (SLE), autoimmune disease end stage renal (ESRD), inflammatory disorder. Method Certa...

Histiocytic sarcoma is a rapidly progressive and fatal neoplastic disease in dogs. It is unclear whether costimulatory molecules, including CD28, cytotoxic T-lymphocyte-associated antigen-4 (CTLA-4), and programmed death-1 (PD-1), are expressed on peripheral blood lymphocytes (PBLs) of canine patients with histiocytic sarcoma. The objective of this study was to evaluate the expression of CD28, ...

CD7 and CD28 are T cell Ig superfamily molecules that share common signaling mechanisms. To determine roles CD7 and CD28 might play in peripheral lymphocyte development and function, we have generated CD7/CD28-double-deficient mice. CD7- and CD28-single-deficient and CD7/CD28-double-deficient mice had normal levels of CD4 and CD8-single-positive T cells in thymus and spleen. However, CD28-defic...

While the ligand of inducible co-stimulator (ICOS), B7 homologous protein, is widely expressed in somatic cells, B7-1 and B7-2 expression is mainly limited to lymphoid organs. Thus, the activation of T cells through ICOS without a CD28-mediated signal may occur in physiological situations. In order to gain a better understanding of the role of the ICOS co-stimulatory signal in immune responses,...

Slow recovery of T-cell numbers and function contributes to the high incidence of life-threatening infections after cytotoxic cancer therapies. We have tested the therapeutic potential of a novel class of superagonistic CD28-specific antibodies that induce polyclonal T-cell proliferation without T-cell receptor engagement in an experimental rat model of T lymphopenia. We show that in lethally i...

The influence of costimulation on the activation of naive CD8+ T cells and thymocytes was studied in vitro using H-Y-specific TCR-transgenic mice and H-Y antigenic peptide. Using a variety of physiological APC types, the activation of naive CD8+ T cells depended strictly on costimulation, which could not be substituted by high epitope density. T cell activation is known to be regulated by the i...

Humanized mice are expected to be useful as small animal models for in vivo studies on the pathogenesis of infectious diseases. However, it is well known that human CD8(+) T cells cannot differentiate into effector cells in immunodeficient mice transplanted with only human CD34(+) hematopoietic stem cells (HSCs), because human T cells are not educated by HLA in the mouse thymus. We here establi...