# Coccomyxa subellipsoidea KJ Components Enhance the Expression of Metallothioneins and Th17 Cytokines during Human T Cell Activation

## TL;DR

A green alga called Coccomyxa subellipsoidea KJ boosts metallothionein and Th17 cytokine expression in T cells, suggesting potential for immunoregulatory drugs or functional foods.

## Contribution

This study reveals that C-KJ components regulate T cell function via metallothionein and Th17 pathways, partially mediated by STAT-3.

## Key findings

- C-KJ fractions P and AS enhance metallothionein and Th17 cytokine gene expression in stimulated T cells.
- AS maintains MT2A mRNA levels and influences Th17 cytokine secretion kinetics.
- STAT-3 inhibition reduces MT2A expression, linking Th17 responses to metallothionein regulation.

## Abstract

Coccomyxa subellipsoidea KJ (C-KJ) is a green alga with unique immunoregulatory characteristics. Here, we investigated the mechanism underlying the modification of T cell function by C-KJ components. The water-soluble extract of C-KJ was fractionated into protein (P) and sugar (S) fractions acidic (AS), basic (BS), and neutral (NS). These fractions were used for the treatment of peripheral blood mononuclear cells stimulated with toxic shock syndrome toxin-1. Transcriptome analysis revealed that both P and AS enhanced the expression of the genes encoding metallothionein (MT) family proteins, inflammatory factors, and T helper (Th) 17 cytokine and suppressed that of those encoding Th2 cytokines in stimulated T cells. The kinetics of MT1 and MT2A gene expression showed a transient increase in MT1 and maintenance of MT2A mRNA after T cell stimulation in the presence of AS. The kinetics of Th17-related cytokine secretion in the early period were comparable to those of MT2A mRNA. Furthermore, our findings revealed that static, a STAT-3 inhibitor, significantly suppressed MT2A gene expression. These findings suggest that the expression of MTs is involved in the immune regulatory function of C-KJ components, which is partially regulated by Th17 responses, and may help develop innovative immunoregulatory drugs or functional foods.