Reducing Blk expression in B6.<i>lpr</i> mice affects proinflammatory cytokine production by macrophages, dendritic cells and kidney.

<p>(<b>A</b>) Splenocytes from 3-month-old B6, Blk^+/−, B6.<i>lpr</i> and Blk^+/−.<i>lpr</i> mice were stimulated with Leukocyte Activation Cocktail for 4 hours. Dot plots showing IL-10 versus IL-6 expression in gated macrophages (F4/80⁺ CD3^– CD19^–). Numbers represent percentage of IL-6⁺ and IL-10⁺ cells. Adjacent graph compares the number of IL-6⁺ macrophages between 3-month-old B6 (n = 4) and Blk^+/− (n = 4) mice and between 3-month-old B6.<i>lpr</i> (n = 7) and Blk^+/−.<i>lpr</i> (n = 8) mice. (<b>B</b>) Comparison of serum IFNα levels between 3-month-old B6 and Blk^+/− mice and between 3-month-old B6.<i>lpr</i> and Blk^+/−.<i>lpr</i> mice. Each symbol represents an individual mouse. (<b>C</b>) Purified pDCs from 2-month-old B6.<i>lpr</i> (n = 3) and Blk^+/−.<i>lpr</i> (n = 3) mice were stimulated with CpG ODN 2395 for 24 hours and supernatants were collected and assayed for IFNα by ELISA. (<b>D</b>) Splenocytes from 3-month-old B6.<i>lpr</i> (n = 4) and Blk^+/−.<i>lpr</i> mice (n = 4) were stimulated with Leukocyte Activation Cocktail for 4 hours. Dot plots showing CD3 versus TNFα expression in gated CD3⁺ T cells (top), B220 versus TNFα expression in gated DCs (center), and F4/80 versus TNFα expression in gated macrophages (MΦs) (bottom). Numbers represent percentages of TNFα⁺ cells. Very few (≤0.5%) B cells were TNFα⁺. (<b>E</b>) Expression data for <i>Il17a</i>, <i>Il17f</i>, <i>Il17c</i> and <i>Il23a</i> from RT² profiler array. Data were normalized to <i>Gapdh</i> levels and are presented as fold change over 3-month-old B6.<i>lpr</i> kidney (set to 1). Data represent 4 to 5 mice per genotype. *<i>p</i> ≤ 0.05; **<i>p</i> ≤ 0.01; #<i>p</i> ≤ 0.001.