Peptide MHCII tetramers to detect endogenous calnexin specific CD4 T cells
The present application discloses proteins or peptides and methods of using such proteins or peptides to evaluate the immune status of a patient. In one embodiment, proteins or peptides may be used to detect endogenous calnexin specific CD4 T cells. In one preferred embodiment, the proteins or peptides may comprise peptide-MHCII tetramers (pMHC tetramers).
1. A method for evaluating an immune status of a patient immunized against a fungus, the method comprising the steps of:
a) obtaining peptide-MHCII tetramers, wherein the peptide-MHCII tetramers comprise a peptide selected from the group consisting of SEQ ID NOs:1-5, 7, and 8;
b) exposing a patient's sample to a suitable amount of the pMHCII tetramers wherein the patient's sample comprises helper T cells;
c) identifying helper T cells in the patient's sample specific for the peptide-MHCII tetramers;
d) quantifying the helper T cells identified in step (c) in the patient's sample;
e) vaccinating the patient against a fungus;
f) repeating steps (b)-(d) after vaccinating against the fungus,
wherein the immune status of a patient against the fungus is obtained by comparing the quantity of the helper T cells specific for the peptide-MHCII tetramers before and after vaccinating the patient against the fungus.
2. The method of claim 1 , wherein the sample is a fresh blood sample.
3. The method of claim 1 , wherein the peptide-MHCII tetramers comprise at least one fluorescent label.
4. The method of claim 1 , wherein identifying helper T cells in the patient's sample comprises using a spectroscopy technique to identify helper T cells.
5. The method of claim 4 , wherein the spectroscopy technique is fluorescence.
6. The method of claim 1 , wherein the fungus is either a dimorphic fungus or non-dimorphic fungus.
7. The method of claim 6 , wherein the dimorphic fungus is selected from a group consisting of Histoplasma, Coccidiodes, Paracoccidioides, Penicillium, Blastomyces , and Sporothrix.
8. The method of claim 1 , wherein the fungus is selected from a group consisting of Blastomyces dermatitidis, Histoplasma capsulatum, Aspergillus fumigatus, Fonsecea pedrosoi , and Geomyces destructans.
9. The method of claim 1 , wherein the peptide-MHCII tetramers comprise a calnexin peptide selected from the group consisting of SEQ ID NOs:1-5, 7, and 8 covalently linked by a flexible linker to a MHCII β chain; and
a MHCII α chain.
10. The method of claim 1 , wherein step d) further comprises detecting expression of one or more markers in the T cells, the markers selected from the group consisting of: interferon gamma (IFN-γ), interleukin 17 (IL-17), CD44, CCR6, CXCR3, and CD62 ligand (CD62L).
11. The method of claim 10 , wherein detecting expression comprises detecting expression by flow cytometry.
12. A method comprising the steps of:
a) obtaining peptide-MHCII tetramers, wherein the peptide-MHCII tetramers comprise a peptide selected from the group consisting of SEQ ID NOs:1-5, 7, and 8;
b) exposing a patient's sample to a suitable amount of the peptide-MHCII tetramers, wherein the patient's sample comprises helper T cells;
c) identifying helper T cells in the patient's sample specific for the peptide-MHCII tetramers.
13. The method of claim 12 , further comprising:
d) quantifying the helper T cells in the patient's sample specific for the peptide-MHCII tetramers.
14. The method of claim 12 , wherein the patient is in need of a bone marrow or stem cell transplant.
15. The method of claim 12 , wherein the patient has been diagnosed with cancer, has undergone organ transplantation, has been diagnosed with acquired immune deficiency syndrome (AIDS), is undergoing hemodialysis, has a catheter, is suffering from severe trauma or burns, has been diagnosed with diabetes mellitus, or has indwelling intravenous tubes.