Lymphoblastic transformation

Four different amounts of the four gangliosides were added to microtiter wells containing human PBMC s and 18 micrograms of concanavalin-A. All four gangliosides markedly inhibited lymphoblastic transformation when 12.6 nanomoles was added to the cultures with a total volume of 0.2 ml (Table II). As little as 1.6-nanomoles of GDlb and GTlb resulted in substantial inhibition, while much less inhibition occurred with equivalent amounts of GM1 and GDla. 

Sugden B, Marsh K, Yates J (1985), A vector that replicates as a plasmid and can be efficiently selected in B-lymphoblasts transformed by Epstein-Barr virus, Mol. Cell. Biol. 5 410-413. 

Lymphoblast transformation test, the leukocyte migration inhibition test with specific allergen (Kaczmarski et al. 1997). 

Intravenous pre-testing is unrehable in determining susceptibility in one survey of 33 400 patients, most of the reactions were not predicted by pretesting, although a positive pre-test did indicate an increased risk of a reaction (39). The value of the lymphoblast transformation test is very limited, although it certainly provides interesting evidence that contrast media can sometimes act as antigens (SEDA-16, 531) (40). 

Synthetic chemicals such as poly(inosinic) poly(cytidilic) acid [poly(IC)] and poly(IC) plus poly(lysine) [poly(ICL)], which are interferon inducers lev-amisole also is reported to increase phagocytosis, stimulate lymphoblast transformation, and increase delayed hypersensitivity reactions when their functions are depressed. 

The peripheral leukocytes of the 10 patients were also studied in vitro using a microtitre method for assay of histamine. In 7 patients (including the 3 patients with positive lymphoblast transformation tests), the leukocytes released more than 10% of their histamine content following exposure to diatrizoate. The significance of this finding is less certain since it may have been due to a direct pharmacological effect. 

In chronic myelogenous leukemia (CML) as well as in a subset of acute lymphoblastic leukemia (ALL) Bcr-Abl, a fusion protein of c-Abl and the breakpoint cluster region (bcr), is expressed in the cytosol of leukemic cells. This fusion protein forms homo-oligomeric complexes that display elevated kinase activity and is the causative molecular abnormality in CML and certain ALL. The transforming effect of Bcr-Abl is mediated by numerous downstream signaling pathways, including protein kinase C (PKC), Ras-Raf-ERK MAPK, JAK-STAT (see below), and PI3-kinase pathways. 

Lymphoblast. A morphologically immature lymphocyte an activated lymphocyte that has been transformed in response to antigenic stimulation. 

Emamghoreishi M, Schhchter L, li PP, et al High intracellular calcium concentrations in transformed lymphoblasts from subjects with bipolar I disorder. Am J Psychiatry 154 976-982, 1997... 

Small lymphocytes from horses were transformed into larger radioresistant lymphoblast-hke cells following stimulation by phytohemagglutinin in vitro. One hundred rads x-irradiation killed all the small lymphocytes, but only around one-third of the lymphoblast-like cells (Dewey and Brannon, 1976). Horse lymphocytes were more radiosensitive than human lymphocytes. The ratios between doses inducing the same effect are 1.3,1.7, and 9.4 for the number of binucleated cells with micronuclei, micronucleus frequency in binucleated cells, and DNA synthesis inhibition, respectively (Catena et al, 1997). 

Organic and aqueous feverfew powdered leaf extracts were found to inhibit IL-1-induced prostaglandin E2 release from synovial cells, IL-2-induced thymidine uptake by lymphoblasts, and mitogen-induced uptake of thymidine by peripheral blood mononuclear cells (PBMCs) (23). Parthenolide also inhibited thymidine uptake by PBMCs. Both parthenolide and the extracts were cytotoxic to the PBMCs and synovial cells thus, the anti-inflammatory effects of feverfew may be secondary to cytotoxicity. These results reflect those of previous researchers who found parthenolide and other sesquiterpene lactones to be cytotoxic to cultures of human fibroblasts, human laryngeal carcinoma cells, and human cells transformed with simian virus 40 (24). 

DE was used to identify cellular proteins in T and B acute lymphoblastic leukaemia cell lines (Mohammad et al, 1994b). Two B cell and two T cell lines as well as a normal Epstein-Barr virus-transformed line of B cell origin were studied. Despite the great similarities in the patterns of the B and T cell derived from 2-DE gels, three proteins appeared to be unique to B cells, whereas eight proteins were unique to T cell lines. It is not known if these proteins are markers for B or T acute lymphoblastic leukaemia, respectively, or if they are unique to the cell lines that were studied. 

Harms, K., et al. (1981). Purification and Characterization of Human Lysosomes from EB-virus Transformed Lymphoblasts, Cell Res. 131 251-266. 

The lymphocyte transformation test, first proposed as a morphological assessment of lymphoblast production in culture upon incubation with the antigenic drug (Heitmann and Kuwert 1966 Halpern et al. 1967), was soon used in its biochemical version, based on measurement of DNA synthesis and [ HJthymidine uptake (Rose et al. 1966 Vischer 1966 Evans 1967 Fellner et al. 1967 a Assem and Vickers 1972 Sarkany and Gaylarde 1978 Warrington and Tse 1979). Al-... 

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