Human endotoxin tolerance is associated with enrichment of the CD14+ CD16+ monocyte subset.

Prior exposure to lipopolysaccharides (LPS) induces a state of cell resistance to subsequent LPS restimulation, known as endotoxin tolerance, mainly by repressing the expression of pro-inflammatory cytokines. We established an endotoxin tolerance model in human monocytes Endotoxin-tolerant cells showed a decrease in IκBα degradation and diminished expression of Tumor necrosis factor (TNF) (both messenger RNA [mRNA] and protein content). The myeloid differentiation factor 88 (MyD88)/MyD88 splice variant (MyD88s) ratio, an indirect way to test the Toll-like receptor 4 (TLR4) MyD88-dependent signaling cascade, did not change in endotoxin-tolerant cells when compared to LPS-stimulated or -unstimulated ones.

Revisiting human IL-12Rβ1 deficiency: a survey of 141 patients from 30 countries.

Interleukin-12 receptor β1 (IL-12Rβ1) deficiency is the most common form of Mendelian susceptibility to mycobacterial disease (MSMD). We undertook an international survey of 141 patients from 102 kindreds in 30 countries. Among 102 probands, the first infection occurred at a mean age of 2.

Clinical disease caused by Klebsiella in 2 unrelated patients with interleukin 12 receptor beta1 deficiency.

Patients with interleukin 12 (IL-12)p40 or IL-12 receptor β1 (IL12Rβ1) deficiencies are prone to develop infections caused by mycobacteria and salmonella; other infections have only been rarely observed. In this report we describe 2 unrelated patients with complete autosomal recessive IL12Rβ1 deficiency who suffered from sepsis attributable to Klebsiella pneumoniae. A Mexican boy suffered from disseminated bacille Calmette-Guérin disease and infections caused by K pneumoniae and Candida albicans and had a fatal outcome.