IgA production by various spleen cells.

<p>(A) IgA production by B cells increased when cocultured with T cells and/or dendritic cells (DCs). (B) Under low zinc (Zn) conditions, IgA production was significantly increased in the presence of DCs. Under high Zn conditions, IgA production by all cell combinations was suppressed. (C) Coculture of untreated B cells with low Zn-treated T cells and/or DCs. IgA production increased in the presence of DCs. (D) Coculture of B cells and DCs with or without lipopolysaccharide (LPS). LPS significantly enhanced IgA production despite the absence of T cells. (E) Coculture of B cells and DCs from gddY or BALB/c mice. A combination of both B cells and DCs from gddY mice yielded the highest production of IgA. **p<0.01; ***p<0.001.</p

Serum concentration of immunoglobulins for each dietary zinc condition.

<p>Dietary zinc intervention altered the serum concentrations of IgA and IgA–IgG immune complexes but not of IgG and IgM. *p<0.05.</p

Expression of Toll-like receptor 4, MyD88, TRIF, and interferon-β in each zinc condition.

<p>(A) Expression of Toll-like receptor 4 (TLR4) for each zinc (Zn) condition with/without lipopolysaccharide (LPS). Expression of TLR4 was significantly increased when stimulated by LPS under low and normal Zn conditions. However, TLR4 expression under high Zn conditions was low despite LPS stimulation. (B) Expression of MyD88 at each Zn condition. Expression of MyD88 remained constant at each Zn condition. (C) Expression of TRIF for each Zn condition. Expression of TRIF under low Zn conditions was significantly higher than that in other groups. (D) Expression of interferon-β in each Zn condition. Expression of interferon-β was higher in low Zn condition and lower in high Zn condition. *p<0.05; **p<0.01.</p

Urinary albumin levels for each dietary zinc condition.

<p>Urinary levels of albumin were significantly higher in the low zinc (Zn) diet group and lower in the high Zn diet group on the sixth week. *p<0.05; **p<0.01.</p

Intensity of mesangial IgA and IgG deposition.

<p>The intensity of IgA and IgG deposition was scored on a 1–5 scale based on an average of more than 10 glomeruli. IgA deposition was significantly attenuated in the high zinc (Zn) diet group. IgG deposition in the low Zn diet group was significantly higher than that in the normal and high Zn diet groups. *p<0.05; **p<0.01.</p

Reactivity against lipopolysaccharide.

<p>Lipopolysaccharide (LPS) was nasally administered to some mice in each dietary group, while others received saline as a vehicle control; samples were collected during the sixth week. We calculated the ratio (sixth:fourth week) of each parameter. Although ACR in all groups increased after LPS stimulation, the elevation in the low zinc (Zn) diet group was very high. Serum concentrations of IgA and IgA–IgG immune complexes (ICs) in the low and normal Zn diet groups tended to be higher after LPS stimulation. However, the high Zn diet group maintained low concentrations of serum IgA and IgA–IgG ICs despite LPS stimulation. *p<0.05.</p