The capacity of pertussis toxin (PT) to induce maturation and functional activities of human monocyte-derived dendritic cells (DCs) was investigated. Both native PT (nPT) and genetically detoxified PT (dPT) efficiently promoted expression on DCs of CD80, CD86, human leukocyte antigen-DR, and CD83 markers, alloreactive antigen presentation, and cytokine production, primarily interferon (IFN)-gamma. Although they did not affect interleukin (IL)-10 production by lipopolysaccharide (LPS)-stimulated DCs, both nPT and dPT strongly synergized with LPS for IL-12 production. PTs plus LPS-stimulated DCs secreted soluble factors fostering IFN-gamma but not IL-4 and IL-5 production by naive T cells. T helper type 1 (Th1) polarization was, as alloreactive antigen presentation, inhibited by anti-IL-12 monoclonal antibody. These findings support the notion that nPT, in addition to inducing specific immune response, is a potent Th1 adjuvant and that dPT fully preserves this adjuvanticity. The synergic interaction between PT and LPS in IL-12 production might be relevant for the mechanisms of vaccine-induced protection.

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Cell-mediated immunity (CMI) and antibody responses to Bordetella pertussis antigens were assessed 4-6 years after primary infant immunization with diphtheria-tetanus tricomponent acellular pertussis (DTaP) or diphtheria-tetanus (DT) vaccine in a country with high endemicity of B. pertussis infection. CMI to the B. pertussis antigens (especially to the pertussis toxin [PT]) was more frequent and/or intense in DTaP than in DT recipients. No lymphoproliferation differences were found between those with and without a history of pertussis although the DT recipients produced very little interferon-gamma after antigen (particularly PT and filamentous hemagglutinin [FHA]) stimulation. In contrast, seropositivity to PT, but not to pertactin or FHA, was more frequent in DT recipients with history of pertussis than in all other subjects. Thus, years after disease or vaccination, CMI response to PT or circulating PT antibodies appears to be the main distinctive feature of pertussis-protected DTaP recipients or pertussis-affected DT recipients.

In addition to its catalytic activities as ecto-NAD+ glycohydrolase (NADase), CD38 displays the ability to transduce signals of biological relevance. Indeed, ligation of CD38 on peripheral blood mononuclear cells (PBMC) by agonistic monoclonal antibodies (mAbs) is followed by the transcription and secretion of a vast array of regulatory cytokines. The present work addresses the issue of whether the signals leading to calcium (Ca2+) mobilization, lymphocyte proliferation and release of cytokines is dependent on the epitopes recognized by the individual mAbs. Competition binding analysis identifies two families of mAbs, namely IB4, IB6 and AT2 on one side and OKT10, SUN-4B7 and AT1 on the other. Each mAb family binds epitopes that are completely or partially common. However, the functional activities of the CD38 molecule can not be simply attributed to the epitopes engaged: for instance, IB4 and OKT10 mAbs, which bind different epitopes, perform as agonistic mAbs in inducing PBMC proliferation and interferon (IFN)-gamma secretion. SUN-4B7 yields intermediate effects, whereas IB6, AT1 and AT2 mAbs are totally ineffective. The effects mediated by IB4 and OKT10 mAbs are apparent in 80% of the healthy individuals studied, whereas the effects of SUN-4B7 mAb operate only in 25% of the donors. Interleukin (IL)-6 secretion was observed in all individuals analyzed, irrespective of the epitopes triggered and of mAbs used to ligate the CD38 molecule. In addition, IB4 is the only mAb able to induce significant intracellular Ca2+ fluxes.

(1) We aimed to compare articular eminence inclination (AEI) in normo-divergent subjects (SN^GoGn = 32° ± 5°), with different anteroposterior sagittal skeletal classes through a cone beam computed generated tomography (CBCT). (2) In this cross-sectional study, CBCT records were retrospectively analysed. From the original sample of 52 CBCT records, 33 records of normo-divergent adult subjects were selected (11 Class I, 13 Class II and 9 Class III). On mid-sagittal section of the Temporomandibular Joint (TMJ) on both sides, AEI was calculated by graphic method. (3) The Kruskal–Wallis test was used to evaluate any difference between AEI on both left and right sides in the three groups. No statistically significant difference was observed on either the right side (p = 0.174) or the left side (p = 0.624). (4) Articular eminence inclination seems to be not related with skeletal class. Given the lack of significance in the observed differences between AEI and skeletal classes, we believe that future studies should focus on assessing possible relationships between AEI and different vertical skeletal patterns.