Inhibition of T- and B-lymphocyte functions by normal immunosuppressive protein

Immunology
|September 1, 1975
PubMed

Normal immunosuppressive protein (NIP) isolated from human plasma was studied in two well defined systems. (1) Spontaneous rosettes of sheep red blood cells with human peripheral blood lymphocytes and PHA-induced lymphocyte cytotoxicity as indicators for T-cell function. (2) Rosette formation tests of human lymphocytes with antibody-coated erythrocytes or erythrocytes coated with antibody and complement as well as antibody-induced lymphocyte-mediated cytotoxicity represented non-T-cell activity. While NIP did not inhibit the formation of any of the above mentioned rosettes, it practically prevented both PHA-induced and antibody-mediated lymphocyte cytotoxicity. Relatively small amounts of NIP inhibited PHA-induced cytotoxicity while higher doses were required for the inhibition of antibody-mediated lymphocyte cytotoxicity. Possible mechanisms of its suppressive activity are discussed. NIP was found to be heat-stable and did not show any species specificity, as NIP preparations from human plasma were immunosuppressive in human, mouse and guinea-pig systems.

Related Concept Videos

Cell-mediated Immune Responses01:40

Cell-mediated Immune Responses

Overview
Abnormal Proliferation02:23

Abnormal Proliferation

Under normal conditions, most adult cells remain in a non-proliferative state unless stimulated by internal or external factors to replace lost cells. Abnormal cell proliferation is a condition in which the cell's growth exceeds and is uncoordinated with normal cells. In such situations, cell division persists in the same excessive manner even after cessation of the stimuli, leading to persistent tumors. The tumor arises from the damaged cells that replicate to pass the damage to the daughter...
Special Features of Adaptive Immunity01:20

Special Features of Adaptive Immunity

The adaptive immune system, a crucial component of the overall immune response, offers a highly specialized defense against pathogens. It involves specific cell types and features, enabling it to combat infections effectively and efficiently.
The primary cell types involved in adaptive immunity are T cells and B cells. Each type has a unique role in defending the body against pathogens. T cells are responsible for cell-mediated immunity. They identify and eliminate infected cells directly,...
T Cell Types and Functions01:24

T Cell Types and Functions

When T cells with CD4 markers are activated, they give rise to two types of effector cells: helper T cells and regulatory T cells. Meanwhile, T cells with CD8 markers differentiate into effector cytotoxic T cells. The differentiation of CD4 T cells into helper T cell subsets, such as Th1, Th2, and Th17 cells, is dependent on the antigen type, antigen-presenting cell, and regulatory cytokines.
Th1 cells stimulate dendritic cells to express necessary co-stimulatory molecules on their surfaces for...
Immunodeficiency Diseases01:25

Immunodeficiency Diseases

Immunodeficiency disorders are conditions in which the immune system's ability to fight infectious disease and cancer is compromised or entirely absent. The immune system comprises a complex network of cells, tissues, and organs that work together to protect the body from potentially harmful invaders. When this system is deficient or not functioning properly, it leaves the body susceptible to infections, diseases, or other complications.
There are three main causes of immunodeficiency disorders...
Inhibitors of Viral Protein Synthesis01:30

Inhibitors of Viral Protein Synthesis

Protein synthesis is indispensable for viral replication, as viruses lack the cellular machinery required for this process and must hijack the host's translational apparatus. In response, host cells deploy a critical innate immune defense involving interferons, specialized cytokines that play a central role in inhibiting viral propagation.Upon viral detection, infected cells release interferons that bind to receptors on adjacent uninfected cells, activating the JAK-STAT signaling pathway and...