α-Fetoprotein Influence on the Conversion of Naïve T-Helpers into Memory T-Cell Effector Subpopulations

AFP-Inhibiting Fragments for Drug Delivery: The Promise and Challenges of Targeting Therapeutics to Cancers

Alpha fetoprotein (AFP) plays a key role in stimulating the growth, metastasis and drug resistance of hepatocellular carcinoma (HCC). AFP is an important target molecule in the treatment of HCC. The application of AFP-derived peptides, AFP fragments and recombinant AFP (AFP-inhibiting fragments, AIFs) to inhibit the binding of AFP to intracellular proteins or its receptors is the basis of a new strategy for the treatment of HCC and other cancers. In addition, AIFs can be combined with drugs and delivery agents to target treatments to cancer. AIFs conjugated to anticancer drugs not only destroy cancer cells with these drugs but also activate immune cells to kill cancer cells. Furthermore, AIF delivery of drugs relieves immunosuppression and enhances chemotherapy effects. The synergism of immunotherapy and targeted chemotherapy is expected to play an important role in enhancing the treatment effect of patients with cancer. AIF delivery of drugs will be an available strategy for the targeted treatment of cancer in the future.

The effects of human pregnancy-specific β1-glycoprotein preparation on Th17 polarization of CD4+ cells and their cytokine profile

BACKGROUND

Pregnancy-specific β1-glycoproteins are capable of regulating innate and adaptive immunity, exerting predominantly suppressive effects. In this regard, they are of interest in terms of their pharmacological potential for the treatment of autoimmune diseases and post-transplant complications. The effect of these proteins on the main pro-inflammatory subpopulation of T lymphocytes, IL-17-producing helper T cells (Th17), has not been comprehensively studied. Therefore, the effects of the native pregnancy-specific β1-glycoprotein on the proliferation, Th17 polarization and cytokine profile of human CD4⁺ cells were assessed.

RESULTS

Native human pregnancy-specific β1-glycoprotein (PSG) at а concentration of 100 μg/mL was shown to decrease the frequency of Th17 (RORγτ⁺) in CD4⁺ cell culture and to suppress the proliferation of these cells (RORγτ⁺Ki-67⁺), along with the proliferation of other cells (Ki-67⁺) (n = 11). A PSG concentration of 10 μg/mL showed similar effect, decreasing the frequency of Ki-67⁺ and RORγτ⁺Ki67⁺ cells. Using Luminex xMAP technology, it was shown that PSG decreased IL-4, IL-5, IL-8, IL-12, IL-13, IL-17, MIP-1β, IL-10, IFN-γ, TNF-α, G-CSF, and GM-CSF concentrations in Th17-polarized CD4⁺ cell cultures but did not affect IL-2, IL-7, and MCP-1 output.

CONCLUSIONS

In the experimental model used, PSG had а mainly suppressive effect on the Th17 polarization and cytokine profile of Th17-polarized CD4⁺ cell cultures. As Th17 activity and a pro-inflammatory cytokine background are unfavorable during pregnancy, the observed PSG effects may play a fetoprotective role in vivo.

[The role of alpha-fetoprotein in regulation of the cytokine profile of activated T-helpers and their conversion in Th17 phenotype]

We studied the effect of the native (non-recombinant) alpha-fetoprotein (AFP) on differentiation, proliferation, and cytokine profile of activated helper T cells 17 (Th17). The object of the study was a culture of isolated by immunomagnetic separation helper T cells (CD4+), induced into the Th17 phenotype by using TCR-activator and proinflammatory cytokines (IL-1β and IL-6). AFP had not significant effect on the frequency of Th17 cells (ROR-γτ+) in the helper T cell culture, and did not affect proliferation of these cells, as measured by Ki-67 expression. Evaluation of the cytokine profile of culture supernatants by using the Luminex xMAP technology, revealed that AFP did not affect the levels of IL-4, IL-5, IL-7, IL-8, IL-10, IL-17, IFN-γ and TNF-α, but at concentrations of 50 IU/ml and 100 IU/ml it increased IL-2 production by activated helper T cells. At the same time, AFP suppressed the synthesis of G-CSF and GM-CSF (10 IU/ml), but stimulated the production of CCL4/MIP-1β (100 IU/ml) and CCL2/MCP-1 chemokines (10 IU/ml and 50 IU/ml).