Downregulation of Anti-B16 Melanoma Immune Responses by Suppressor T Lymphocytes.

An experimental condition was established in vivo for selectively eliminating hapten-reactive suppressor T-cell activity generated in mice primed with a para-azobenzoate (PAB)-mouse gamma globulin (MGG)-conjugate and treated with PAB-nonimmunogenic copolymer of D-amino acids (D- glutamic acid and D-lysine; D-GL). The elimination of suppressor T-cell activity with PAB-D-GL treatment from the mixed populations of hapten- reactive suppressor and helper T cells substantially increased apparent helper T-cell activity. Moreover, the inhibition of PAB-reactive suppressor T-cell generation by the pretreatment with PAB-D-GL before the PAB-MGG-priming increased the development of PAB-reactive helper T-cell activity. The analysis of hapten-specificity of helper T cells revealed that the reactivity of helper cells developed in the absence of suppressor T cells was more specific for primed PAB-determinants and their cross-reactivities to structurally related determinants such as meta-azobenzoate (MAB) significantly decreased, as compared with the helper T-cell population developed in the presence of suppressor T lymphocytes. In addition, those helper T cells generated in the absence of suppressor T cells were highly susceptible to tolerogenesis by PAB-D- GL. Similarly, the elimination of suppressor T lymphocytes also enhanced helper T-cell activity in a polyclonal fashion in the T-T cell interactions between benzylpenicilloyl (BPO)-reactive T cells and PAB- reactive T cells after immunization of mice with BPO-MGG-PAB. Thus inhibition of BPO-reactive suppressor T-cell development by the BPO-v-GL- pretreatment resulted in augmented generation of PAB-reactive helper T cells with higher susceptibility of tolerogenesis to PAB-D-GL. Thus, these results support the notion that suppressor T cells eventually suppress helper T-cell activity and indicate that the function of suppressor T cells related to helper T-cell development is to inhibit the increase in the specificity and apparent affinity of helper T cells in the primary immune response. The hapten-reactive suppressor and helper T lymphocytes are considered as a model system of T cells that regulate the immune response, and the potential applicability of this system to manipulating various T cell-mediated immune responses is discussed in this context.

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Quantitating Effector and Regulatory T Lymphocytes in Immune Responses by Limiting Dilution Analysis Modeling

The Journal of Immunology ◽

10.4049/jimmunol.174.6.3421 ◽

2005 ◽

Vol 174 (6) ◽

pp. 3421-3431 ◽

Cited By ~ 4

Author(s):

Thierry Bonnefoix ◽

Philippe Bonnefoix ◽

Pascal Perron ◽

Jian-Qing Mi ◽

Wan Fai Ng ◽

...

Keyword(s):

T Lymphocytes ◽

Immune Responses ◽

Regulatory T Lymphocytes ◽

Limiting Dilution Analysis ◽

Limiting Dilution

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Some Immunological Parameters Paraw in Women with vaginal candidiasis

Baghdad Science Journal ◽

10.21123/bsj.4.2.191-194 ◽

2007 ◽

Vol 4 (2) ◽

pp. 191-194

Author(s):

Baghdad Science Journal

Keyword(s):

T Lymphocytes ◽

Immune Responses ◽

Blood Cells ◽

Vaginal Candidiasis ◽

Control Group ◽

Differential Count ◽

Immunological Parameters ◽

Phagocytosis Index

This study was conducted to know some Immune responses in women with vaginal candidias is by Candidia species. Hemoglubin (Hb) was decreased significantly in patient women comparing with control group. The differential count of Blood cells revealed that neutrophils and monocytcs were increased significantly in patient women comparing with control group. The percentage of the Phagocytosis index was decreased significantly in patient women (66.45 + 15.05) comparing with control group (73.72 + 3.77) and the T- lymphocytes were decreased also in patient women (57.75 + 18.787) comparing with control group (74.25 + 7.759).

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Decrease in generation of reactive oxygen species by neutrophils from patients with infectious mononucleosis: role of suppressor T lymphocytes

Blood ◽

10.1182/blood.v64.5.994.bloodjournal645994 ◽

1984 ◽

Vol 64 (5) ◽

pp. 994-999

Author(s):

Y Niwa ◽

T Sakane ◽

Y Miyachi ◽

T Kanoh ◽

K Somiya

Keyword(s):

Reactive Oxygen Species ◽

T Lymphocytes ◽

Infectious Mononucleosis ◽

Disease Onset ◽

Reactive Oxygen ◽

Control Group ◽

Ros Generation ◽

Oxygen Species ◽

Suppressor T Lymphocytes ◽

Subsets Of T Lymphocytes

We assessed the generation of reactive oxygen species (ROS: O2-, H2O2, OH . , chemiluminescence) by neutrophils and monocytes from six patients with infectious mononucleosis, ten patients with other viral diseases, and ten normal controls. Neutrophils from infectious mononucleosis patients showed markedly decreased generation of all reactive oxygen species, compared with the two control groups; this abnormality persisted for four to eight weeks after disease onset. Monocytes from these patients generated normal levels of ROS. Normal neutrophils incubated with T lymphocytes from infectious mononucleosis patients generated significantly less of each ROS than did those incubated with T cells from either control group. T cell-mediated suppression of ROS generation required both OKT4+ cells from infectious mononucleosis patients and OKT8+ cells from either patients or normals. We conclude that the generation of reaction oxygen species in neutrophils is suppressed in patients with infectious mononucleosis, at least in part, by interacting subsets of T lymphocytes.

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