If the collaborative requirement of Lyt 1 T helper cells is bypassed by the Lyt 1 T cell-derived mediator of T help, termed Il-2, upon antigenic stimulation, PNA+ Lyt 123 thymocytes differentiate into either alloreactive or H-2-restricted PNA- Lyt 23 cytotoxic effector cells. Along the differentiation pathway from Lyt 123 leads to 23 effector cells, cytolytic activity is carried out by T cells ...

CTL are thought to play a role in the elimination of transformed cells in vivo. The effectiveness of such CTL is in part dependent on recognition of tumor specific antigens. Among the best characterized tumor-specific antigens are the unique or idiotypic determinants on the Ig of B cell lymphomas. Here we describe the generation and properties of human CTL specific for the idiotype on autologou...

Cytotoxic T lymphocytes mediate lysis of target cells by various mechanisms, including exocytosis of lytic proteins (perforin, granzymes) and receptor-ligand binding of Fas/APO molecules. Death of target cells is characterized by either necrosis or apoptosis, depending on the killing mechanism used and on the metabolism of the target cell itself.

Along with the development of new technology, the molecular mechanisms of the generation of functional CTLs have been elucidated over the last several years which together will undoubtedly enhance our progression towards the development of successful vaccines for the many chronic viral infections and cancer. It has been shown that the activation of naı̈ve CTLs requires all three signals to be fu...

Research on CTLs has been booming in recent years—there are more than 250 papers related to CD8 T-cells published everymonth.With such rapid advancement in this particular aspect of immunology alone, it is important to summarize and report information on this hot topic in a timely and organized fashion. Although the submission window for this issue was open for a significantly shorter period co...

Antigen recognition by cytotoxic lymphocytes (CTL) 1 and by helper T cells is restricted by gene products of the major histocompatibility complex (MHC), called H-2 in the mouse (1). CTL recognize antigens in the context of Kand D-regionencoded structures, whereas helper T cells recognize antigen in the context of I-regionencoded structures. This H-2 restriction appears to be very tight: C T L s...

CTLs play a critical role in �ghting chronic virus infection and cancers. Despite the tremendous efforts spent so far, generating potent and highly effective CTLs remain a major roadblock for disease control (prevention and therapies). Activation of CTLs requires different stimuli and is in�uenced by different disease conditions. In this special issue, several papers investigated functions of c...

A 15-year-old Japanese man was referred for evaluation of heart failure. Conventional heart failure therapy had little effect, and severe left ventricular dysfunction as well as elevated erythrocyte sedimentation rate persisted. Magnetic resonance angiography showed aortic dilatation with wall thickening characteristic of Takayasu's arteritis. An endomyocardial biopsy specimen revealed infiltra...