A functional division of T- cells can be based on the cytokines they produce:
TH1 type
• | interferon gamma and IL-2 |
• | augment cell-mediated immune response by activating macrophages (e.g. delayed type hypersensitivity reactions) |
TH2 type
• | augment humoral response, and inhibit some cell mediated response |
• | IL-4 --> hypergammaglobulinemia; switch in the antibody isotype from IgM to IgE |
• | IL-10 --> reduction in cell mediated immunity |
diseases:
Psoriasis --> (CLA+) CD8 T-cells with Th 1 cytokines Th2 in the early phases; Th1 in the late and chronic phases
Allergic contact dermatitis --> (CLA+) CD8 T-cells with variable cytokine profile (both Th1 and Th2 cytokines)
Atopic dermatitis --> (CLA+) CD4 T-cells with Th2 cytokines
Mycosis Fungoides --> a tumor of (CLA+) CD4 T-cells
CTCL:
• | both resting and stimulated cells from the blood of patients with leukemic CTCL make cytokines of the Th2 type |
• | the most commonly encountered malignant cutaneous T-cell is a Th2 CD45RO+ CLA+ T-cell |
eosinophilic folliculitis:
• | preliminary evidence from both peripheral blood and skin of patients with eosinophilic folliculitis show the lymphocytes are making IL-4 and IL-5 but are not making gamma interferon or IL-2 |
Leishmaniasis:
• | Th2 – disseminated infection (therefore some treat with interferon gamma and antimony) |
Leprosy:
• | tuberculoid leprosy - Th2 |
• | lepromatous leprosy - Th1 |
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