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Objective This study aimed to investigate the role of zinc sulphate in immune regulation in Artemisia annua pollen-challenged P815 mastocytoma cells. Methods P815 mastocytoma cells were treated with various concentrations of zinc sulphate and Artemisia annua pollen. Cell proliferation was measured using the Cell Counting Kit-8. The amount of ST2 and p38 in the cells were measured using Western blotting. The level of interleukins (IL)-33 in the supernatant was determined using the enzyme-linked immunosorbent assay. The levels of IL-2, IL-4, IL-5, interferon-γ, and tumor necrosis factor were measured using the cytometric bead array. Results Artemisia annua pollen at a concentration >0.001 µg/mL induced allergic response in the P815 mastocytoma cells. Expressions of IL-33, IL-4, ST2, and p38 increased along with higher concentrations of Artemisia annua pollen. Zinc sulphate of 50-200 µmol/L promoted the proliferation of P815 mastocytoma cells. Zinc sulphate attenuated the upregulation of IL-33, IL-4, ST2, and p38 caused by Artemisia annua pollen. Conclusion Zinc sulphate can promote the proliferation of P815 mastocytoma cells. It can also attenuate allergic response in the P815 mastocytoma cells induced by Artemisia annua pollen, which might provide a new treatment method for allergic diseases.

Ocular immune privilege preserves the visual axis by preventing the induction of sight-threatening nonspecific inflammation. Although privilege is essential for maintaining visual integrity, intraocular tumors exploit the privileged environment and grow progressively within the anterior chamber of the eye. Recently, a large number of laboratories have constructed genetically engineered tumor cell vaccines that express high levels of costimulatory signals. These vaccines are designed to bypass the normal pathways of T-cell activation and directly activate CD8+ tumor-specific T cells. In the following series of experiments, we determined whether a tumor cell vaccine that uses costimulatory signals (CD80 and IL-12) is capable of eliminating tumors within the immune-privileged anterior chamber. As expected, vaccine-immunized mice rejected subcutaneous flank tumors (a non-privileged site). However, the vaccine failed to protect mice from even a small number of tumor cells transplanted into the immune-privileged anterior chamber. Surprisingly, immunized mice that were simultaneously challenged with subcutaneous and anterior chamber tumors were unable to eliminate tumors at either site. The failure of systemic protective immunity coincided with the loss of tumor-specific delayed hypersensitivity and cytotoxic T cells. We conclude that tumor cell vaccines that induce complete protection against tumors in non-immune-privileged sites fail to protect against the same tumor within an ocular immune-privileged site. Moreover, a tumor that escapes elimination within the eye can terminate systemic protective immunity that is induced by the tumor cell vaccine.

Purpose: To examine the effects of intravitreal Mycobacteria tuberculosa adjuvant (MTA) on ocular immune privilege., Methods: MTA was injected into the vitreous cavity of BALB/c mouse eyes to induce anterior uveitis. The inflamed eyes were then examined for their capacity to afford immune privilege to injected allogeneic tumor cells and to promote anterior chamber-associated immune deviation (ACAID). Aqueous humor (AqH) was tested for IL-12 content and for its ability to inhibit T-cell activation., Results: AqH removed from MTA-inflamed eyes at 6 and 12 h contained high levels of IL-12, which then fell almost to baseline at 24 h. This is relevant to the finding that the inflamed eye failed to support ACAID induction at an early time period and then regained the ACAID-induction capability at a later time. Nonetheless, AqH removed from MTA-inflamed eyes retained its capacity to suppress T-cell activation, and MTA-inflamed eyes afforded extended survival to alloantigenic tumor cells implanted into the anterior chamber., Conclusion: Intraocular inflammation evoked by MTA causes the local accumulation of IL-12 and simultaneously robs the eye of its capacity to promote systemic immune tolerance to eye-derived antigens. However, MTA-inflamed eyes retain immune privilege, as indicated by their support of the progressive growth of allogeneic tumor cells.