ANTIGENS FOR DETECTING TOXOPLASMA INFECTION BY MONITORING CELLULAR IMMUNITY
Antigens of Toxoplasma gondii that provide specific and strong delayed type hypersensitivity (DTH) immune response, or which stimulate IFN-γ secretion, are used for testing subjects for infection. Any skin testing format may be adapted for testing for the delayed type hypersensitivity, including a patch, a needle, or a prong. Presence of DTH indicates infection. Alternate methods of detecting a T cell response including monitoring IFN-γ secretion may be used.
1 . A Toxoplasma gondii -derived antigen composition, wherein the composition comprises a Toxoplasma gondii -derived antigen selected from the group consisting of:
a. isolated and purified MIC1, MIC3, MIC4, or MIC6,
b. truncated MIC1, MIC3, MIC4, or MIC6,
c. extended MIC1, MIC3, MIC4, or MIC6,
d. a fusion protein comprising any two or more of MIC1, MIC3, MIC4, or MIC6,
e. a fusion protein of any of MIC1, MIC3, MIC4, or MICE with a moiety that enhances or facilitates purification, recombinant production, or immune cell stimulation, and
f. combinations thereof.
2 . The antigen composition of claim 1 which is produced in bacteria and comprises less than 0.1 EU/ml lipopolysaccharide.
3 . A kit comprising (a) a Toxoplasma gondii -derived antigen composition of claim 1 and (b) an applicator device for administration of the Toxoplasma gondii -derived antigen to a subject.
4 . The kit of claim 3 wherein the Toxoplasma gondii -derived antigen composition is separately packaged within the kit.
5 . The kit of claim 3 wherein the applicator device is separately packaged within the kit.
6 . The kit of claim 3 wherein the applicator device comprises a patch.
7 . The kit of claim 3 wherein the applicator device comprises a needle.
8 . The kit of claim 3 wherein the applicator device comprises a prong.
9 . The kit of claim 8 wherein the applicator device delivers the composition percutaneously.
10 . A method of delivering Toxoplasma gondii -derived antigen to a subject comprising:
contacting an applicator device which is loaded with the Toxoplasma gondii -derived antigen composition of claim 1 with skin of the subject, whereby the Toxoplasma gondii -derived antigen composition is delivered to the skin of the subject.
11 . The method of claim 10 wherein the applicator device comprises a patch.
12 . The method of claim 10 wherein the applicator device comprises a needle.
13 . The method of claim 10 wherein the applicator device comprises a prong.
14 . The method of claim 13 wherein the applicator device delivers the composition percutaneously.
15 . An applicator device for administering one or more Toxoplasma gondii -derived antigens to a mammal, comprising one or more Toxoplasma gondii -derived antigens, wherein the Toxoplasma gondii -derived antigens are selected from the group consisting of:
a. isolated and purified MIC1, MIC3, MIC4, or MIC6,
b. truncated MIC1, MIC3, MIC4, or MIC6,
c. extended MIC1, MIC3, MIC4, or MIC6,
d. a fusion protein comprising any two or more of MIC1, MIC3, MIC4, or MIC6,
e. a fusion protein of any of MIC1, MIC3, MIC4, or MICE with a moiety that enhances or facilitates purification, recombinant production, or immune cell stimulation, and
f. combinations thereof.
16 . The applicator device of claim 15 which comprises a plurality of prongs to which a plurality of Toxoplasma gondii -derived antigens has been applied.
17 . The applicator device of claim 15 wherein the applicator comprises one or more prongs which are configured to receive a liquid comprising Toxoplasma gondii -derived antigen and to puncture skin to deliver the Toxoplasma gondii -derived antigen percutaneously.
18 . The applicator device of claim 15 wherein the Toxoplasma gondii -derived antigens are devoid of GRA7.
19 . The applicator device of claim 15 which comprises a patch for transdermal administration.
20 . The applicator device of claim 15 which comprises a needle.
21 . A method of eliciting a T cell response in a subject comprising:
contacting a Toxoplasma gondii -derived antigen composition of claim 1 with T cells of the subject, whereby the Toxoplasma gondii -derived antigen composition induces a T cell response.
22 . The method of claim 21 wherein the response is a delayed type hypersensitivity response.
23 . The method of claim 21 wherein the response is release of a cytokine.
24 . The method of claim 21 wherein the response is release of interferon-γ.
25 . The method of claim 21 wherein the T cells are in peripheral blood mononuclear cells.
26 . The method of claim 21 wherein the T cells are in a blood sample.
27 . The method of claim 21 wherein the contacting is performed in vitro.
28 . The method of claim 21 further comprising the step of detecting or quantifying release of a cytokine.
29 . The method of claim 21 further comprising the step of detecting or quantifying release of interferon-γ.