The activation molecule CD40 and the death receptor CD95/Fas play important roles in regulating B cells so that effective antimicrobial immunity occurs without autoimmunity. CD40 signaling increases CD95 expression, sensitizing cells to apoptosis, but sustained CD40 signals rescue B cells from CD95 killing. Here we describe a mechanism of early CD40-mediated rescue from CD95-induced apoptosis in B cells. Maximal rescue was achieved when CD40 signals were given within 1-2 h of initiating CD95 apoptosis. CD40 signaling did not block association of Fas-associated death domain-containing protein with CD95, but decreased CD95-induced activation of caspases 3 and 8. Rapid CD40 rescue did not require NF-jB activation and was independent of de novo protein synthesis, but was dependent upon active PI3 K. Signaling via a CD40 mutant that does not bind TNFR-associated factor (TRAF)1, TRAF2, and TRAF3 rescued B cells from CD95-induced apoptosis. TRAF1/2/3-independent rescue was confirmed in B cell lines made deficient in these TRAF molecules by gene targeting. In contrast, CD40 rescue was completely abrogated in TRAF6-deficient B cells, which showed reduced activation of Akt in response to CD40 engagement. These results reveal a new rapid mechanism to balance B cell activation and apoptosis. IntroductionB cells integrate many signals that direct proliferation and differentiation into Ig-secreting plasma cells or longlived memory cells. Ultimately, activated B cells can be eliminated through apoptosis, which is important for maintaining immune tolerance and homeostasis [1,2]. Molecules of the TNFR family play critical roles in regulating the balance between B cell activation and apoptosis. CD40 signals allow B cells to proliferate, differentiate, switch isotype, form GC, and become memory cells [3][4][5]. CD40 stimulation also induces upregulation of other members of the TNFR family, including the death receptor CD95/Fas [6].The importance of CD95 in maintaining lymphocyte homeostasis and tolerance is highlighted by the human disease autoimmune lymphoproliferative syndrome (ALPS), caused by mutations in the CD95 signaling pathway [7,8] autoantibodies are produced, and systemic autoimmunity develops [9]. Expression of the CD95 transgene exclusively in T cells of lpr/lpr mice is sufficient to decrease lymphadenopathy, splenomegaly, and the accumulation of abnormal T cells, but these mice still produce autoantibodies, causing deposition of immune complexes in kidney glomeruli [10]. In contrast, expression of the CD95 transgene in both B and T cells reduces the levels of serum Ig, autoimmune symptoms, and mortality [11]. Thus, CD95 signaling in B cells is crucial for maintaining peripheral tolerance and preventing autoimmunity. When CD95 is oligomerized, either by binding to its ligand on T cells (CD95L) or by Ab against its extracellular domain, it recruits the adaptor molecule Fas-associated death domain-containing protein (FADD) and procaspase 8 into a complex called the deathinducing signaling complex (DISC) that cleaves pro...

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Doctors are required to notify Child Protective Services (CPS) if parents do not provide appropriate medical care for their children. But criteria for reporting medical neglect are vague. Which treatments properly fall within the realm of shared decision-making in which parents can decide whether to accept doctors’ recommendations? Which treatments are so clearly in the child’s interest that it would be neglectful to refuse them? When to report medical neglect concerns to CPS may be controversial. It would seem inhumane to allow a child to suffer because of parental refusal to administer proper analgesia. In this ethics rounds, we present a case of an adolescent with chronic pain who is terminally ill. Her parents were not adherent to recommended analgesia regimens. Her palliative care team had to decide whether to report the case to CPS.

End-of-life care for many infants involves the withdrawal of mechanical ventilation. Usually this takes place in the hospital environment, but sometimes parents request that their infant dies at home. Facilitating this has significant practical and resource implications and raises both logistical and ethical questions. In this article, we report a neonatal case involving home extubation, explaining the processes involved as well as providing an ethical context.

Jake was diagnosed with autism at the age of four. His symptoms were treated with behavioral therapy until the age of 14, when he began having frequent angry outbursts. He often shouted at his parents and had fits of screaming, occasionally at school. At the time, his mother noticed that he was very irritable and often seemed depressed. He was prescribed an SSRI and an atypical antipsychotic for his outbursts and mood symptoms. Now 17, Jake has cognitive abilities in the low-normal range, but his ability to perform daily activities is more substantially impaired, and his mother is heavily involved in his care. He needs reminders and supervision to care for himself, including taking his medication and doing his homework, and refuses to brush his teeth or hair unless his mother insists. He experiences sensory overload. He attends an alternative high school because of his repeated angry outbursts at school and difficulties paying attention.

In this article, we report a novel, unreported SCN1A mutation in a 3-year-old girl with Dravet syndrome. She has an insertional mutation of an adenine nucleotide immediately adjacent to base pair 1566 in exon 10, resulting in a premature stop codon at amino acid 524. We review the current literature on Dravet syndrome, also known as severe myoclonic epilepsy in infancy.