Mutant human T cell line producing immunosuppressive factor and method for obtaining such mutants
AssigneeOrtho Pharmaceutical Corporation
InventorCatherine Y. Lau
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Abstract
A stable mutant human T cell line is disclosed which secretes a high titer suppressor inducer factor. This suppressor inducer factor in turn induces production of a T cell suppressor factor which suppressed mitogen-induced T cell proliferation at high dilution. Also disclosed is a general method for mutating lymphoblastoid cell lines to yield mutants secreting enhanced levels of lymphokines.
Claims24
The stable 6-thioguanine resistant mutant T lymphoblastoid cell line ATCC CRL 8296, which mutant secretes constitutively a high titer of a T-cell suppressor inducer factor which is:
- (i) non-mitogenic;
- (ii) non-cytotoxic;
- (iii) inactivated by 30 minutes at 56.degree. C.;
- (iv) suppresses at least 90% of mitogen-induced T cell proliferation at a dilution of 10.sup.-6 ;
- (v) does not suppress mitogen-induced B cell proliferation at a dilution of 10.sup.-6 ;
- and
- (vi) does not suppress pokeweed mitogen induced Ig synthesis by B cells at 10.sup.-1 dilution.
A human suppressor factor which is antigen non-specific and which:
- (a) at a dilution of up to 10.sup.-6 suppresses at least 90% of mitogen induced T cell proliferation;
- (b) does not suppress mitogen-induced B cell proliferation at a dilution of up to 10.sup.-6 ;
- (c) does not suppress pokeweed mitogen induced Ig synthesis by B cells at 10.sup.-1 dilution;
- (d) is inactivated by 30 minutes at 56.degree. C.;
- (e) is contained in a high molecular weight protein of about 110,000 dalton;
- (f) exhibits maximum suppressor activity at physiological pH;
- (g) suppresses the proliferation of both OKT4+ and OKT8+ T cell populations;
- (h) is non-mitogenic and non-cytotoxic;
- and
- (i) suppresses mouse spleen cell proliferation to mitogenic stimulation with the same potency as it suppresses human peripheral blood lymphocyte proliferation to mitogenic stimulation.
Dependencies are inferred from the claim text.