CD4-positive T-cells

Wu XM, Osoegawa M, Yamasaki K, Kawano Y, Oclii H, Horiuclii I, Minohai a M, Ohyagi Y, Yamada T, ICira JI (2000) Flow cytometric differentiation of Asian and Western types of multiple sclerosis, HTLV-1-associated myelopatliy/ti opical spastic pai apai esis (HAM/TSP) and hyperlgEaemic myelitis by analyses of memory CD4 positive T cell subsets and NK cell subsets. J Neurol Sci 177 24-31. 

CHAPTER 35, FIGURE 15 Major histocompatibility complex (MHC) proteins class II. The MHC class II proteins bind and present and present peptides that are synthesized outside the infected cell, i.e., peptides that are derived from proteins of the infecting organisms, bound to their specific T-cell receptors (TcRs). Interaction and stimulation of T-cell proliferation occurs with CD4 positive T cells (Figure 35-16). The figure is derived from the coordinates published in the Protein Data Bank file 1A6A. 

Mahon, B.D. et al. (2003) The targets of vitamin D depend on the differentiation and activation status of CD4 positive T cells. Journal of Cellular Biochemistry, 89, 922-932. 

Over a period of time, these CD4-positive T-cells are destroyed, as much by the activated killer T-cells as by the virus itself, and the loss of these cells is evidenced by the lowering of the numbers of detectable CD4-positive cells. These should normally number around 800-1200 per cubic millimetre of blood, but this count drops initially to around 500 in HIV-positive patients and then to less than 200 in patients with full-blown AIDS. This process may take a few years, but typically takes around 10 years. 

M. Suzuki, M. Iwashiro, F. Takatsuki, K. Kuribayjishi, J. Hamuro, Reconstitution of antitumor effects of lentinan in nude mice Roles of delayedtype hypersensitivity reaction triggered by CD4-positive T cell clone in the infiltration of effector cells into tumor, Japan J. Cancer Res., 85,409-417,1994. 

In 1982, an extracorporeal form of 8-MOP photochemotherapy (photopheresis) was developed by Edelson et al. for the treatment of cutaneous T-cell lymphoma, a CD4-positive T-cell malignancy. Photopheresis was also found to be effective in a number of other T-cell-mediated diseases. Clinical trials demonstrated beneficial effects in pemphigo vulgaris, severe atopic dermatitis, AIDS-related complex, rheumatoid arthritis, and systemic lupus erythematosus. ... 

More sensitive tests for HIV are under development. This is important because in an HIV-infected individual, most cells are not infected, even among CD4-positive T lymphocytes and monocytes/macrophages. Newly developed techniques are dependent on molecular genetics (Dl). 

T cells are lymphocytes produced by the thymus gland. There are two types of T cells involved in immune response CD4+ (CD positive, helper cells) and CD8 (CD positive, also called T killer, or suppressor, cells). When the APCs present the antigens to CD4+ helper T cells, the secretory function is activated and growth factors such as cytokines are secreted to signal the proliferation of CD8" killer cells and B cells. When the CD8" ... 

Quantitative T lymphocyte surface phenotyping (CDS, CD4, CDS) target CDS positive T cells less than 25 cells/mm. ... 

Participation of the T-cell subsets was also examined histochemically in subcutaneously rechallenge tumor sections, Fig. (6)-Protocol C. The accumulation of lymphocytes in the tumor tissues and around the tumor increased in the CVS-treated group, 2 days after the s.c. tumor rechallenging, Fig. (8)-B. Immunohistochemical staining revealed increased infiltration of mature CD3 (D), CD4 (F), and CD8 (H) -positive T-cell s into the tissue in the CVS group. The tumor mass disappeared in about 50 percent of the CVS-treated mice 7 days after tumor inoculation, while in all control PBS mice it increased progressively until death (data not shown). 

In the regional lymph nodes, the numbers of CD4 or CD8 single positive and CD4CD8 double positive T cells increased in the PBS controls, and the increment was augmented markedly by CVS, Fig. (11). A similar tendency was observed in the numbers of these cells in the contralateral lymph nodes, but to a lesser event. 

Misc Extrathymic Cortical thymus Cortical thymus Cortical thymus double positive T cells (CD4/CD8) Medullary thymus... 

The activation of the stress systems affects all tissues of the organism, and the peripheral immune system is no exception. These effects are mediated through at least tw o pathways via the HPA axis and by virtue of the innervation of lymphatic tissues by autonomic nerve fibers, especially from the sympathetic nervous system. All lymphoid tissues, primary (bone marrow and thymus) as well as secondary (spleen, lymph nodes, and gut-associated lymphoid tissue) are innervated by sympathetic nerve fibers. As discussed above, most lymphoid cells express catecholamine receptors, including B-lymphocytes, CD4- and CD 8-positive T cells, dendritic cells, monocytes, and macrophages. 

AIDS Acquired Immunodeficiency Syndrome (AIDS) is an acquired Idefect of cellular immunity associated with infection by the human immunodeficiency virus (HIV), a CD4-positive T-lymphocyte count under 200 cells/pL or less than 14% of total lymphocytes, and increased susceptibility to opportunistic infections and malignant neoplasms. Clinical manifestations also include emaciation (wasting) and demen-... 

The majority of small lymphocytes in early MS lesions and in the hypercellular edge of plaques extending into normal white matter are CD4-positive T lymphocytes.108110 T lymphocytes of the CD8 phenotype are present in early lesions but this population predominates in later lesions.111 Examination of the distribution of T-lymphocyte subsets in MS plaques of different activity has led to the proposal that CD4-positive cells are responsible for the development and expansion of lesions, whilst the CD8-positive subset controls their local activity.110112... 

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