Lymphocyte proliferation assay

Ex vivo studies have revealed that trichothecenes can both inhibit and stimulate leukocyte function.12 For example, trichothecenes are toxic to alveolar macrophages,13 but drive differentiation of human myeloid leukemic cells.14 Dose-dependent decreases or increases in B- and T-cell mitogen responses are observable in lymphocytes from animals exposed to T-2 toxin, DON, or various macrocyclic trichothecenes these toxins similarly impair or enhance mitogen-induced lymphocyte proliferation in vitro.12 Rank order of inhibitor potency in rodent and human lymphocyte proliferation assays is Type D > Type A group > Type B group and is dependent on degree of acylation as well as of uptake and metabolism. 

Perron GM, Jusko WJ. Species- and gender-related differences in cyclosporine/prednisolone/sirolimus interactions in whole blood lymphocyte proliferation assays. J Pharmacol Exp Ther 1998 286 191-200. 

Gummert JF, Otto G, Barten MJ, Morris RE. Effect of anesthesia on a whole blood lymphocyte proliferation assay in the rat. Immnnopharmacol Immunotoxicol 1999 21 267-276. 

A variety of techniques have been employed to assess the immune response to beryllium. Ho vever, the ease, sensitivity, and specificity have made the lymphocyte proliferation assay using H-thymidine the standard technique (Rossman et al. 1988, Mroz et al. 1991). In the past, this technique has been referred to as the lymphocyte transformation test (LTT), but transformation is an older term that is no longer applicable. The cells respond by proliferating (a normal process) and are not transformed, which today implies a malignant process. Hence, the test is currently known as the lymphocyte proliferation test (LPT). 

Interleukin-2 Human recombinant lL-2 aldesleukin, proleukin des-alanyl-1, serine-125 human lL-2) differs from native lL-2 in that it is not glycosylated, has no amino terminal Ala, and has an Ser substituted for the Cys at amino acid 125. The potency of the preparation is represented in International Units in a lymphocyte proliferation assay such that 1.1 mg of recombinant lL-2 protein equals 18 million International Units. Aldesleukin has the following in vitro biologic activities of native lL-2 enhancement of lymphocyte proliferation and growth of lL-2-dependent cell lines enhancement of lymphocyte-mediated cytotoxicity and killer cell activity and induction of interferon-7 activity. In vivo administration of aldesleukin in animals produces multiple immunologic effects in a dose-dependent manner. Cellular immunity is profoundly activated with lymphocytosis, eosinophilia, thrombocytopenia, and release of multiple cytokines e.g., TNF-a, lL-1, interferon-7). Aldesleukin is indicated for the treatment of adults with metastatic renal cell carcinoma and melanoma. Administration of aldesleukin has been associated with serious cardiovascular toxicity resulting from capillary leak syndrome, which involves loss of vascular tone and leak of plasma proteins and fluid into the extravascular space. Hypotension, reduced organ perfusion, and death may occur. An increased risk of disseminated infection due to impaired neutrophil function also has been associated with aldesleukin treatment. 

Molecules that damage or affect normal bone marrow functions may induce immunotoxicity as well, since bone marrow is the site of hematopoiesis. Clinical manifestations of drug-induced myelotoxicity include peripheral pancytopenia if stan cells or all hematopoietic lineages are involved or anemia, leukopenia, and/or thrombocytopenia, if only specific lineages are affected (Carey, 2(X)3 Evans, 2008). Typical bone marrow culture assays focus on granulocyte, monocyte, megakaryocyte, and/ or erythroid lineages. Lymphopoiesis can be evaluated by other functional assays such as lymphocyte proliferation assays, which may include assessment of proliferation of individual lymphoid subsets. For more details on assessment of bone marrow toxicity, please see ChapterIV.il. 

Lymphocyte proliferation assay according to a modified method of Wagner and Jur-cic [7]... 

Biological activities of LTB4 are measured by che-motactic assay, granule enzyme release assay, superoxide generation, hamster cheek pouch vascular permeability assay, rat mesenteric venule leukocyte adherence and emigration assay, lymphocytes proliferation assay, and leukocyte adhesion assay. 

Nickel-specific human T-lymphocyte clones have been isolated from blood [373] and inflammatory infiltrates after nickel application [379, 381]. 7-15% of the CD4 1 8 T-lymphocyte clones appeared to be specific for nickel in a proliferation assay [379] this proliferation response required the presence of antigen-presenting cells and was restricted by HLA class II molecules. Nickel-specific T cells from each nickel-allergic patient were extremely heterogenous with respect to their genetic restriction [381], Nickel-specific T lymphocytes sometimes show unusual genetic restrictions and might even respond to nickel without the participation of HLA-II molecules. 

The basic principle underlying the LLNA is that sensitizers induce a primary proliferation of lymphocytes in the lymph node draining the site of chemical application. This proliferation is proportional to the dose applied and to the potency of the allergen, and provides a measurement of sensitization. The LLNA assesses this proliferation as a dose-response in which the proliferation in test groups is compared to that in vehicle treated controls. The ratio of the proliferation in treated groups to that in vehicular controls, termed the Stimulation Index , is determined, and must be at least three before a test substance can be further evaluated as a potential skin sensitizer. The test substance, plus vehicle and positive control, is applied for three consecutive days to the ears of test mice, on days 4 and 5 the animals are left alone, and on the 6th day they are prepared for the proliferation assay, sacrificed, and the measurements are done. 

The compound was not mutagenic in bacterial assays or genotoxic in sister chromatid exchange assays but was immunotoxic, decreasing the rate of lymphocyte proliferation in... 

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