Mechanisms of Immunomodulation by Drugs

Abstract

Immunomodulators are those extrinsic or intrinsic substances which regulate or alter the scope, type, duration or competency of the immune response. This paper presents an overview of the mechanisms of immunomodulation, and discusses selected chemical and biologic substances which are capable of modifying the immune or biologic response of the organism. The immunopharmacology, including in viva and in pifro assays, of a novel acridine immunomodulator is discussed. This low molecular weight compound is an immunomodulator and anti-cancer adjuvant, which has been shown to induce high levels of circulating interferon in mice, protect mice against lethal viral infection, stimulate macrophage and NK cell cytotoxicity for tumor cells, partially restore humoral and cellular immune responses in tumor bearing immunosuppressed mice, and augment the cytotoxic T-lymphocyte response to syngeneic tumor cells. Tissue changes, consisting of presence of drug bound to lysosomal membranes, perivascular infiltrates in mouse liver, glomerular hyalinization in mouse kidney, and focal myocardial changes in mice are described. The compound persists intracellularly for extended periods of time in cells with high lysosomal activity. The tissue changes are interpreted to be a result of overloading of cellular mechanisms for elimination from the cells involved.

Therapeutic and nutraceutical potentials of a brown seaweed Sargassum fusiforme

“…Immunomodulators are intrinsic and extrinsic substances that regulate or modify the scope, type, duration, or capacity of the immune response (Rasmussen & Arvin, 1982). Diet may affect maintenance of immune homeostasis (Burns & Goodwin, 2004;Derhovanessian, Solana, Larbi, & Pawelec, 2008;Gardner & Murasko, 2002;Gorczynski & Terzioglu, 2008;Lebish & Moraski, 1987). Chen, Nie, Fan, et al (2012)) reported that S. fusiforme can be an efficacious immune-potentiating supplement and that it can be used as an alternative to reduce immunosuppression induced by chemotherapy; therefore, it may be used as an immunostimulant in food and pharmaceutical industries.…”

Plant Extracts, Energy, and Immune Modulation in Broilers

“…Immunomodulation is described as a change of the indicators of cellular and humoral immunity and nonspecific defence factors [15]. Immunomodulation can present as immunosuppression (substances that inhibit the immune system) or immunostimulation (substances that activate or induce the mediators or components of the immune system), thus regulating or altering the scope, type, duration or competency of the immune response [16,17].…”

Immunomodulatory Action of Substituted 1,3,4-Thiadiazines on the Course of Myocardial Infarction

“…However, in the medical literature, one finds multiple and conflicting definitions for the terms immunosuppression and immunomodulation depending on the author, publication, or agency defining these terms [ 1 ]. According to Lebish (1987), immunomodulators are “those intrinsic or extrinsic substances which regulate or alter the scope, type, duration or competency of the immune response” [ 2 ]. The term “regulation”, in this or similar definitions, always includes the ability of substances to upregulate or downregulate specific aspects of the host response [ 3 ].…”

“…According to this point of view, immunomodulators are medicines that restore the functions of the immune system in therapeutic doses (effective immune defense), by lowering the increased and increasing the lowered immunity [ 4 ]. Moreover, some researchers even categorize agents based on the most clinically relevant data, which are the documented occurrences of immune-mediated, clinically relevant complications that are compiled from the actual human data [ 1 , 2 , 3 , 4 , 5 ]. According to them, immunomodulators refer to those agents that modulate the immune response to control inflammatory disease activity without being associated with a statistically significant increased risk of clinically manifested immune-mediated complications [ 1 ].…”

“…Thus, the later definition postulated not only the direction of action (inhibiting or down-regulating) and the state of immune response (the exaggerated), but also the chemical nature of compounds, separating them from vaccines, antibodies, enzymes and cytokines. The FDA’s definition is mostly clear, although it is not without shortcomings, as it excludes some possible mechanisms of action by these agents (described by Lebish, 1987), such as increasing the ability of the host to tolerate damage by cytotoxic modality, augmenting and/or restoring effector mechanisms or mediators of host defense, or replacing the damaged effector or mediator mechanisms [ 2 ]. Moreover, the possible links between the immune response and stress reaction, which often accompany the disturbances of the former, also slip out of sight.…”