scholarly journals Identification of transforming growth factor-beta as a contaminant in factor VIII concentrates: a possible link with immunosuppressive effects in hemophiliacs

Blood ◽  
1994 ◽  
Vol 84 (6) ◽  
pp. 2021-2030
Author(s):  
M Wadhwa ◽  
P Dilger ◽  
J Tubbs ◽  
A Mire-Sluis ◽  
T Barrowcliffe ◽  
...  

In previous studies, we have shown that some, but not all low-, intermediate-, and high-purity factor VIII concentrates inhibit interleukin-2 (IL-2) secretion from phytohemagglutinin (PHA)-stimulated T lymphocytes. We now present evidence that this inhibitory action of concentrates is, at least in part, due to contamination with transforming growth factor-beta (TGF-beta). Originally identified in platelets, TGF-beta is a 25-kD homodimer that has been shown to be a natural and potent inhibitor of many immunologic responses. Using a specific bioassay, we have measured TGF-beta in various factor VIII concentrates. While some concentrates contained substantial amounts of the cytokine, there was a wide variation in concentrations of TGF-beta in different products. These levels correlated with the degree of inhibition of IL-2 secretion from T cells exhibited by each product (P = .0001). Noninhibitory concentrates contained no detectable TGF-beta. Addition of a specific TGF-beta 1 antibody reversed the inhibitory effect of some concentrates on IL-2 secretion by PHA-stimulated Jurkat T cells and interleukin-5 (IL-5)-induced proliferation of an erythroleukemic cell line. These findings suggest that TGF-beta contamination is a major contributory factor to the inhibitory activity of some factor VIII concentrates on cytokine secretion or activity, and may partially explain the reported immunosuppressive effects in recipients of these blood products.

Blood ◽  
1994 ◽  
Vol 84 (6) ◽  
pp. 2021-2030 ◽  
Author(s):  
M Wadhwa ◽  
P Dilger ◽  
J Tubbs ◽  
A Mire-Sluis ◽  
T Barrowcliffe ◽  
...  

Abstract In previous studies, we have shown that some, but not all low-, intermediate-, and high-purity factor VIII concentrates inhibit interleukin-2 (IL-2) secretion from phytohemagglutinin (PHA)-stimulated T lymphocytes. We now present evidence that this inhibitory action of concentrates is, at least in part, due to contamination with transforming growth factor-beta (TGF-beta). Originally identified in platelets, TGF-beta is a 25-kD homodimer that has been shown to be a natural and potent inhibitor of many immunologic responses. Using a specific bioassay, we have measured TGF-beta in various factor VIII concentrates. While some concentrates contained substantial amounts of the cytokine, there was a wide variation in concentrations of TGF-beta in different products. These levels correlated with the degree of inhibition of IL-2 secretion from T cells exhibited by each product (P = .0001). Noninhibitory concentrates contained no detectable TGF-beta. Addition of a specific TGF-beta 1 antibody reversed the inhibitory effect of some concentrates on IL-2 secretion by PHA-stimulated Jurkat T cells and interleukin-5 (IL-5)-induced proliferation of an erythroleukemic cell line. These findings suggest that TGF-beta contamination is a major contributory factor to the inhibitory activity of some factor VIII concentrates on cytokine secretion or activity, and may partially explain the reported immunosuppressive effects in recipients of these blood products.


1988 ◽  
Vol 253 (1) ◽  
pp. 295-298 ◽  
Author(s):  
E J Rayhel ◽  
D A Prentice ◽  
P S Tabor ◽  
W H Flurkey ◽  
R W Geib ◽  
...  

Transforming growth factor-beta (TGF-beta) inhibits proliferation of Nb2 cells, a rat T lymphoma, in response to lactogens and interleukin-2. Prostaglandins may play an important role in the pathway through which TGF-beta exerts its inhibitory actions, because prostaglandin E2 also inhibits proliferation of Nb2 cells, and indomethacin, an inhibitor of prostaglandin synthesis, reverses the inhibitory effects of TGF-beta on Nb2 cell proliferation.


1993 ◽  
Vol 13 (2) ◽  
pp. 1155-1162 ◽  
Author(s):  
T Brabletz ◽  
I Pfeuffer ◽  
E Schorr ◽  
F Siebelt ◽  
T Wirth ◽  
...  

Transforming growth factor beta (TGF-beta) has a growth-inhibitory effect on numerous different cell types of the immune system, including T lymphocytes. We show in this study that the inhibitory action of TGF-beta on T lymphocytes is accompanied by a block of interleukin 2 (IL-2) gene expression which is mediated, at least in part, by inhibition of IL-2 promoter/enhancer activity. The functional analysis of cis-regulatory (proto-enhancer) elements of the IL-2 enhancer/promoter region showed that the most TGF-beta-responsive element maps to its so-called upstream promoter site. The proto-enhancer activity of the upstream promoter site element is also inhibited by cyclosporin A. The upstream promoter site DNA harbors two noncanonical, closely linked binding sequences for octamer and AP-1-like factors. Both sites are involved in the establishment of IL-2 enhancer activity. Since the activity of genuine octamer sites but not that of AP-1-binding sites is also impaired by TGF-beta and cyclosporin A in El4 T lymphoma cells, we conclude that both immunosuppressives interfere with the activity but not the DNA binding of octamer factors in T lymphocytes.


1991 ◽  
Vol 174 (5) ◽  
pp. 1259-1262 ◽  
Author(s):  
B Li ◽  
P K Sehajpal ◽  
A Khanna ◽  
H Vlassara ◽  
A Cerami ◽  
...  

The regulation of mRNA encoding transforming growth factor beta (TGF-beta) and interleukin 2 (IL-2) in normal human T cells was explored using novel competitor DNA constructs in the quantitative polymerase chain reaction and accessory cell-independent T cell activation models. Our experimental design revealed the following: (a) TGF-beta mRNA and IL-2 mRNA are regulated differentially in normal human T cells, quiescent or signaled with the synergistic combinations of: sn-1,2-dioctanoylglycerol and ionomycin or anti-CD3 monoclonal antibody (mAb) and anti-CD2 mAb; (b) the steady-state level of TGF-beta mRNA in the stimulated T cells, in contrast to that of IL-2 mRNA, is increased by the immunosuppressant cyclosporine (CsA); and (c) the paradoxical effect of CsA on TGF-beta mRNA levels is also appreciable at the level of production of functionally active TGF-beta protein. Our findings, in addition to demonstrating the utility of the competitor DNA constructs for the precise quantification of immunoregulatory cytokines, suggest a novel and unifying mechanistic basis for the immunosuppression and some of the complications (e.g., renal fibrosis) associated with CsA usage.


1993 ◽  
Vol 13 (2) ◽  
pp. 1155-1162
Author(s):  
T Brabletz ◽  
I Pfeuffer ◽  
E Schorr ◽  
F Siebelt ◽  
T Wirth ◽  
...  

Transforming growth factor beta (TGF-beta) has a growth-inhibitory effect on numerous different cell types of the immune system, including T lymphocytes. We show in this study that the inhibitory action of TGF-beta on T lymphocytes is accompanied by a block of interleukin 2 (IL-2) gene expression which is mediated, at least in part, by inhibition of IL-2 promoter/enhancer activity. The functional analysis of cis-regulatory (proto-enhancer) elements of the IL-2 enhancer/promoter region showed that the most TGF-beta-responsive element maps to its so-called upstream promoter site. The proto-enhancer activity of the upstream promoter site element is also inhibited by cyclosporin A. The upstream promoter site DNA harbors two noncanonical, closely linked binding sequences for octamer and AP-1-like factors. Both sites are involved in the establishment of IL-2 enhancer activity. Since the activity of genuine octamer sites but not that of AP-1-binding sites is also impaired by TGF-beta and cyclosporin A in El4 T lymphoma cells, we conclude that both immunosuppressives interfere with the activity but not the DNA binding of octamer factors in T lymphocytes.


1990 ◽  
Vol 265 (2) ◽  
pp. 1089-1093 ◽  
Author(s):  
P Kondaiah ◽  
M J Sands ◽  
J M Smith ◽  
A Fields ◽  
A B Roberts ◽  
...  

1988 ◽  
Vol 8 (5) ◽  
pp. 2229-2232 ◽  
Author(s):  
A M Brunner ◽  
L E Gentry ◽  
J A Cooper ◽  
A F Purchio

Analyses of cDNA clones coding for simian type 1 transforming growth factor beta (TGF-beta 1) suggest that there are three potential sites for N-linked glycosylation located in the amino terminus of the precursor region. Analysis of [3H]glucosamine-labeled serum-free supernatants from a line of Chinese hamster ovary cells which secrete high levels of recombinant TGF-beta 1 indicate that the TGF-beta 1 precursor, but not the mature form, is glycosylated. Digestion with neuraminidase resulted in a shift in migration of the two TGF-beta 1 precursor bands, which suggests that they contain sialic acid residues. Endoglycosidase H had no noticeable effect. Treatment with N-glycanase produced two faster-migrating sharp bands, the largest of which had a molecular weight of 39 kilodaltons. TGF-beta 1-specific transcripts produced by SP6 polymerase programmed the synthesis of a 42-kilodalton polypeptide which, we suggest, is the unmodified protein backbone of the precursor. Labeling with 32Pi showed that the TGF-beta 1 precursor was phosphorylated in the amino portion of the molecule.


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