Beneficial innate signaling interference for antibacterial responses by a Toll-like receptor-mediated enhancement of the MKP-IRF3 axis.

A major function of innate immune receptors is to recognize pathogen-associated molecular patterns and then evoke immune responses appropriate to the nature of the invading pathogen(s). Because innate immune cells express various types of these receptors, distinct combinations of signaling pathways are activated in response to a given pathogen. Although the conventional wisdom is that these signaling pathways cooperate with one another to ensure an effective host response, a more nuanced view recognizes antagonism between the individual pathways, where the attenuation of a signaling pathway(s) by others may shape the immune response. In this study, we show that, on Listeria monocytogenes infection, Toll-like receptor-triggered MyD88 signaling pathways suppress type I IFN gene induction, which is detrimental to macrophage bactericidal activity. These pathways target and suppress the IFN regulatory factor 3 (IRF3) transcription factor that is activated by the stimulator of IFN genes-TANK-binding kinase-1 kinase pathway. We also provide evidence for the involvement of the MAPK phosphatase family members, which renders IRF3 hypophosphorylated on Toll-like receptor signaling by enhancing the formation of an MAPK phosphatase-IRF3-TANK-binding kinase-1 ternary complex. This study, therefore, reveals a hitherto unrecognized and important contribution of a beneficial innate signaling interference against bacterial infections.

Tensile and shear bond strengths of a stainless steel used in orthodontic brackets bonded to bovine enamel using two types of resin cement.

The purpose of this study was to examine the relationship between the bond strength of stainless steel with two types of resin cements (MMA- and composite-based) on bovine enamel depending on the directionality of the applied force. The specimens were either placed in water or subjected to thermal cycles (TC), and the shear or tensile bond strengths (SBS or TBS) were determined. The SBS showed significantly greater than the TBS for both types of cement, and the SBS and TBS for composite-based cement had larger than MMA-based one. No significant difference in SBS was observed in the cements even after being subjected to TC. Cohesive failures of the cement and bovine enamel in the composite-based group, while adhesive failures were observed in MMA-based one. Consequently, the direction of the force at both cements affected the retention of stainless steel, and MMA-based cement was preferred when prioritizing less enamel damages.

Lymphoplasmacytic Lymphoma Presenting with Diarrhea and Joint Pain Which was Successfully Diagnosed by an MYD88 Mutation Analysis.

A 55-year-old man presented to our department with diarrhea, weight loss, fatigability, and polyarthralgia. Blood tests revealed elevated soluble interleukin-2 receptor levels and IgG-type M protein positivity, without any findings that were suggestive of collagen disease. After computed tomography (CT) detected enlarged lymph nodes in the abdominal para-aortic region, lymphoma was suspected. CT-guided needle biopsy of the lymph node did not help to achieve a definitive diagnosis; however, a bone marrow test showed the pathological features of B-cell lymphoma. A genetic examination detected a MYD88 L265P mutation; the mutation analysis was valuable in diagnosing lymphoplasmacytic lymphoma in a IgM-type M protein-negative patient.

Functional evaluation of ex vivo expanded cord blood lymphocytes: possible use for adoptive cellular immunotherapy.

OBJECTIVE: To examine the possibility of adoptive cellular immunotherapy such as donor lymphocyte infusion using ex vivo expanded cord blood (CBL) lymphocytes, the potential expansion ability of CBL lymphocytes and the function of expanded CBL lymphocytes were evaluated. MATERIALS AND METHODS: Mononuclear cell fractions derived from CBL or peripheral blood (PBL) were placed in anti-CD3 monoclonal antibody-coated flasks and cultured in the presence of recombinant human interleukin-2 for 4 days. Cells then were transferred to noncoated flasks and cultured for another 2 weeks. On day 14, polyclonality, cell surface markers, killer activity, and intracellular cytokine profiles were evaluated. RESULTS: Cells were polyclonally expanded. The differences in cumulative fold expansion on day 14 between CBL [1174 +/- 637 (292-1939), n = 6] and PBL [1247 +/- 568 (517-2328), n = 9] were not significant (p = 0.95). Phenotypic patterns of both expanded CBL and PBL were similar. CD4/CD8 ratio of expanded CBL appeared to remain greater than 1 on day 8. In contrast, that of expanded PBL became less than 1. In both cases, approximately 20% of cells had the CD3(+)CD8(+)CD56(+) phenotype. At an effector to target ratio (E/T) of 40:1, the natural killer activity of expanded CBL (64.5% +/- 10.8%, n = 9) was significantly higher than that of expanded PBL (48.3% +/- 16.8%, n = 9) (p < 0.01, Mann-Whitney U-test). However, there was no significant difference in lymphokine-activated killer activity between expanded CBL (45.3% +/- 25.2%, n = 7) and expanded PBL (67.2% +/- 12.3%, n = 7). Interferon-gamma-producing cells were dominant in both cases. CONCLUSIONS: It was feasible to achieve approximately 1000-fold expansion of CBL, and the phenotype and function of expanded CBLs were essentially equivalent to those of expanded PBL. This suggested that ex vivo expanded CBL may be applied to adoptive cellular immunotherapy such as donor lymphocyte infusion.