The nature of the helper lymphocytes in lymphocytosis-promoting factor (LPF)-induced proliferation was explored. Removal of macrophages from adherent splenocytes by either carbonyl-iron incubation or passage through Sephadex G-10 columns did not affect their synergistic function. Nor did cytolysis with Thy-1.2 antiserum and complement. The helper cells were found to be surface immunoglobulin-po...

Most retroviral packaging cell lines were established by a helper virus plasmid cotransfected with a separate plasmid encoding a selection marker. Since this selection marker coexisted in trans with the helper virus sequence, helper virus gene expression could be inactivated by host DNA methylation despite selection for the cotransfected selection marker. We have reported that DNA methylation c...

B6.T1a(a) (Qa-1(a)) mice that are primed in vivo and restimulated in vitro with Qa-1 congenic spleen cells from B6 (Qa-1(b)) animals are unable to generate anti-Qa-1(b) cytotoxic T lymphocytes (CTL). This nonresponsive pattern was observed regardless of the route of immunization or the time of testing in vitro. Although B6.T1a(a) mice are nonresponders to Qa-1(b) when presented on B6 cells, the...

T cells with helper and suppressor functions arising during graft-versus-host reaction (B6 vs. BDF1) have been characterized with respect to their Ly surface antigens. Helper cells were found to express the phenotype Ly 1+2- and suppressor cells the phenotype Ly 1+2+. Ly 1-2+ T cells had no suppressive effect in this system. T cells of the host did not contribute to either activity.

ing factors IκBα and A20 are uncommon in nodular lymphocyte-predominant Hodgkin lymphoma. Haematologica. 2010; 95(1):153-7. 35. Monti S, Savage KJ, Kutok JL, Feuerhake F, Kurtin P, Mihm M, et al. Molecular profiling of diffuse large B-cell lymphoma identifies robust subtypes including one characterized by host inflammatory response. Blood. 2005;105(5):1851-61. 36. Lenz G, Wright G, Dave SS, Xia...

Recently, the alteration of peripheral T cells has become a focus of attention in research on Crohn's disease (CD). To examine the characteristics of peripheral T cells in CD patients, we analyzed the expression of a memory T cell marker (CD45RO(Bright)CD3+) and the cytokine production by peripheral helper and cytotoxic T cells in patients with CD. With the use of monensin to prevent the secret...

The immune system is designed to eradicate a large variety of invading pathogens with minimum immunopathology. T helper cells, also known as CD4+ T cells, may be subdivided into the T helper 1 (Th1) and the T helper 2 (Th2) subsets, which produce distinct profiles of cytokines [1,2]. These Th1 and Th2 cells have opposing roles, regulating immune responses to intracellular and extracellular path...

High-affinity antibodies are critical for host protection and underlie successful vaccines. The generation of such antibodies requires T cell–dependent help, which mediates germinal center reactions in which mutation and selection of B cells occurs. Using an interleukin 4–reporter system, we show here that CD4+ follicular helper T cells constituted essentially all of the cytokine-secreting T ce...

Non-transforming helper viruses were isolated from pools of two hamsterspecific sarcoma viruses in which isolations by terminal dilution procedures had previously been unsuccessful. This presumably resulted from approximately equivalent levels of sarcoma and helper viruses in the original pools. Helper virus was isolated from morphologically normal cells selected from tissue culture plates show...

We investigated the antigenic requirements for restimulation of H-2- restricted cytolytic T lymphocytes (CTL) in vitro to determine whether H-2 I region-restricted helper T cells are required in these responses. In one set of experiments, we studied the in vitro response of (responder x nonresponder)F(1) female T cells to the male antigen H-Y. We chose to examine this response because it has be...