Dysregulated expression of both the costimulatory CD28 and inhibitory CTLA-4 molecules in PB T cells of advanced cervical cancer patients suggests systemic immunosuppression related to disease progression.

Unlabelled: Cervical cancer (CC) occurs more frequently in women who are immunosuppressed, suggesting that both local and systemic immune abnormalities may be involved in the evolution of the disease. Costimulatory CD28 and inhibitory CTLA-4 molecules expressed in T cells play a key role in the balanced immune responses. There has been demonstrated a relation between CD28, CTLA-4, and IFN genes in susceptibility to CC, suggesting their importance in CC development.

CD28 downregulation on CD4+ T cells is associated with age of kidney transplant recipient.

There is a growing body of evidence showing that the intensity of rejection is weaker in older kidney allograft recipients while chronic complications, but not rejection, are the main causes of graft loss. To investigate whether the age of the recipient is a factor affecting the expressions of the CD28, CTLA-4, and CD40L costimulatory molecules on CD4+ T cells. Their expression levels were determined in 78 kidney transplant recipients aged 17-68 years.

CD40L, CD28, and CTLA-4 expression on CD4+ T cells in kidney graft recipients: a relationship with post-transplantation clinical course.

Background: Experimental studies have demonstrated that the intensity of alloreactivity against a transplanted organ results from an interaction of positive (CD40/CD40L and B.7/CD28) and inhibitory (B.7/CTLA-4) signals between antigen-presenting cells (APCs) and T lymphocytes.

[Structure and function of lymphocyte TCR/CD3 complex].

The multi-chain T cell receptor/CD3 complex (TCR/CD3) plays a key role in antigen recognition, T cell activation and in consequence in triggering an antigen specific immune response. This process is induced by direct interaction of the TCR receptor with an antigen bound to the major histo-compatible complex on antigen-presenting cells. Upon the structural and functional cooperation of TCR receptor with CD3 complex, the activating signal is transmitted through the cell membrane to the nucleus.

Lack of association between an exon 1 CTLA-4 gene polymorphism A(49)G and multiple sclerosis in a Polish population of the Lower Silesia region.

Multiple sclerosis (MS) a chronic inflammatory demyelinating disease of the central nervous system is believed to have a T cell-mediated autoimmune etiology. The cytotoxic T lymphocyte antigen 4 (CTLA-4) gene is a strong candidate for the involvement in autoimmune diseases because CTLA-4 plays an important role in the downregulation of the early and late stages of T cell activation and the maintenance of peripheral T cell tolerance. To examine the genetic association of the CTLA-4 gene locus with MS, we analyzed an exon 1 CTLA-4 gene polymorphism A(49)G in 102 unrelated Polish MS patients in the Lower Silesia region and 101 age- and sex-matched healthy subjects.

Correlation of blood lymphocyte CTLA-4 (CD152) induction in Hodgkin's disease with proliferative activity, interleukin 2 and interferon-gamma production.

Expression of the downregulatory CTLA-4 molecule was determined on unstimulated and anti-CD3 + recombinant interleukin 2 (rIL-2)-stimulated peripheral blood T cells in Hodgkin's disease (HD) and correlated with the T-cells' proliferative activity, IL-2 and interferon (IFN)-gamma production. There was a negligible percentage of CTLA-4+/CD3+ cells before culture. The mean percentage of CTLA-4+/CD3+ lymphocytes increased gradually, peaked after 72 h of stimulation and returned to basal values after 96 h of stimulation.

CD28 costimulatory molecule--expression, structure and function.

T cell activation is a key event in triggering an antigen specific immune response of the organism. The process is induced primarily by the signal generated by direct interaction of a T cell receptor with an antigen bound to the major histocompatibile complex on an antigen-presenting cell (APC). Although the signal is critical in exciting immune response, an additional, costimulating signal is required.