Tumor-induced alteration in macrophage accessory cell activity on autoreactive T cells

Single cell suspensions of rat lymphoid and nonlymphoid tissues were fractionated on discontinuous gradients of bovine serum albumin into high density and low density subfractions. In general, accessory activity required for responses of periodate-treated T lymphocytes was recovered only in a low density population containing a small percent of the total fractionated cells from lymph nodes, spleen, liver, skin, and peritoneal exudates. Further purification always led to an increase of both accessory activity and number of dendritic cells present in nonrosetting and nonadherent populations. After purification, a high recovery of the total accessory activity was found in fractions that contained a high percentage of dendritic cells resulting in a more than 1,000-fold enrichment in accessory activity per cell. No other fraction obtained during the purification contained significant accessory activity. In all cases, macrophage-enriched populations lacked accessory cell activity. With the exception of peritoneal exudate cell preparations, which contained an inhibitory cell, the level of accessory activity in a given population was always found to be a function of the number of dendritic cells present. Dendritic cells from all sources were nonadherent, nonphagocytic, radio- resistant, and nonspecific esterase negative. They expressed Ia antigens and lacked Fc receptors. Both epidermal and lymph node dendritic cells contain Birbeck granules, subcellular structures previously described only for Langerhans cells. Accessory activity requires viable dendritic cells but is unaffected by 1,000 rad of γ-irradiation. However, ultraviolet irradiation abolished the activity of accessory cells. The cells that responded to periodate were IgG-negative T cells, whereas IgG-positive B cells could not be stimulated under the same conditions. Only periodate-treated T cells and dendritic cells were needed for responses to occur; removal of virtually all macrophages from these purified preparations had no effect. Dendritic cells were also required as stimulators in mixed leukocyte cultures, whereas macrophages, even though Ia positive, were inert.

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The Function of Gingival Lymphocytes on the Establishment of Human Periodontitis

Advances in Dental Research ◽

10.1177/08959374880020022801 ◽

1988 ◽

Vol 2 (2) ◽

pp. 364-367 ◽

Cited By ~ 18

Author(s):

H. Okada ◽

Y. Shimabukuro ◽

Y. Kassai ◽

H. Ito ◽

T. Matsuo ◽

...

Keyword(s):

T Cells ◽

B Cells ◽

B Cell ◽

Mhc Class Ii ◽

Plasma Cell ◽

Cell Activity ◽

Mouse Spleen ◽

Autoreactive T Cells ◽

Hla Dr ◽

Igg Synthesis

Human periodontitis has been confirmed to be an IgG plasma cell-rich lesion. However, we also detected many T cells, both CD4-positive and CD8-positive cells, in periodontal lesions. Some of these T cells expressed HLA-DR (la-like) antigen on their surfaces, and the proportion of HLA-DR+ cells was approximately equal in both CD4+ and CD8+ cell populations (Okada et al., 1983, 1984). Consequently, both helper and suppressor T cells were believed to participate in the establishment of periodontal lesions. On the other hand, B cells were thought to be activated polyclonally in periodontal lesions, because a variety of periodontal florae possessed polyclonal B-cell-activating activity. We demonstrated that Actinomyces viscosus T14V stimulated mouse spleen B cells polyclonally and induced many IgM-producing cells but few IgG-producing cells. Moreover, IgG-producing cells were differentiated from only surface IgG-positive B cells but not from surface IgG-negative B cells-namely, surface IgM- or IgA-positive B cells (Harada et al., 1988). These results suggested that memory B cells, which had already been primed with appropriate antigens, might migrate into periodontal lesions, and then be activated polyclonally and develop into IgG-producing cells. The periodontal lesion could, therefore, be induced by the interactions of immunoregulatory mechanisms of T cells and polyclonal B cell activity of periodontal florae. In fact, L3T4-positive T cells (helper-inducer T cells) enhanced IgG synthesis of mouse spleen B cells which had been activated with T-independent B cell activators such as LPS and A. viscosus preparations (Okada et al., 1987; Ito et al., 1988). We hypothesized from the above results that autoreactive T cells recognized the increasing self-MHC class II(Ia) antigen on B cells which had been activated with polyclonal B cell activators, and then produced soluble factors, which could enhance IgG synthesis of these B cells. Autoreactive T cells as well as PBAs, thus, may play an important role in the establishment of the IgG plasma cell-rich periodontal lesion.

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Involvement of HLA class II molecules in acquisition of staphylococcal enterotoxin A-binding activity and accessory cell activity in activation of human T cells by related toxins in vascular endothelial cells

Clinical & Experimental Immunology ◽

10.1111/j.1365-2249.1992.tb02995.x ◽

2008 ◽

Vol 87 (2) ◽

pp. 322-328 ◽

Cited By ~ 8

Author(s):

T. UCHIYAMA ◽

M. ARAAKE ◽

X. J. YAN ◽

Y. MIYANAGA ◽

H. IGARASHI

Keyword(s):

T Cells ◽

Endothelial Cells ◽

Vascular Endothelial Cells ◽

Cell Activity ◽

Binding Activity ◽

Accessory Cell ◽

Vascular Endothelial ◽

Staphylococcal Enterotoxin A ◽

Human T Cells ◽

Hla Class Ii Molecules

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Apoptosis and proliferation ofperipheral blood T-cells as alternative processes in pathogenesis of diabetes mellitus type 1

Medical alphabet ◽

10.33667/2078-5631-2019-1-4(379)-16-20 ◽

2019 ◽

Vol 1 (4) ◽

pp. 16-20 ◽

Cited By ~ 1

Author(s):

A. V. Lugovaya ◽

N. M. Kalinina ◽

V. Ph. Mitreikin ◽

Yu. P. Kovaltchuk ◽

A. V. Artyomova ◽

...

Keyword(s):

Diabetes Mellitus ◽

T Cells ◽

High Risk ◽

Peripheral Blood ◽

Cellular Response ◽

Proliferative Potential ◽

Autoreactive T Cells ◽

Alternative Processes

Apoptosis, along with proliferation, is a form of lymphocyte response to activating stimuli. In the early stages of cell differentiation, the apoptotic response prevails and it results to the formation of tolerance to inductor antigen. Mature lymphocytes proliferate in response to stimulation and it means the initial stage in the development of the immune response. Since in this case apoptosis and proliferation acts as alternative processes, their ratio can serve as a measure of the effectiveness of the cellular response to activating signals. The resistance of autoreactive T-cells to apoptosis is the main key point in the development of type 1 diabetes mellitus (T1DM). Autoreactive T-cells migrates from the bloodstream to the islet tissue of the pancreas and take an active part in b cells destruction. The resistance of autoreactive effector T-cells to apoptosis may suggest their high proliferative potential. Therefore, the comparative evaluation of apoptosis and proliferation of peripheral blood lymphocytes can give a more complete picture of their functional state and thus will help to reveal the causes of ineffective peripheral blood T-ceiis apoptosis in patients with T1DM and will help to understand more deeply the pathogenesis of the disease. in this article, the features of proliferative response of peripheral blood T-cells in patients with T1DM and in individuals with high risk of developing T1DM have been studied. Apoptosis of T-cell subpopulations has been investigated. The correlation between the apoptotic markers and the intensity of spontaneous and activation- induced in vitro T-cells proliferation of was revealed. it was determined, that autoreactive peripheral blood T-cells were resistant to apoptosis and demonstrated the increased proliferative potential in patients with T1DM and in individuals with high risk of developing T1DM.

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