Citations

Abstract Limited empirical data have been available on the adult sequelae of childhood homelessness. Using nationally representative data from the National Epidemiologic Survey of Alcohol and Related Conditions-III, we compared a hierarchy of adults who were never homeless, those who were only homeless as children, and those who were homeless both as children and adults, hypothesizing greater adversity as one moved up the three-level hierarchy on sociodemographic, behavioral, and lifetime mental health diagnostic characteristics. As a further evaluation of the status of adults who were homeless as both children and adults, we compared this highest risk group to those who had been homeless only as adults. Individuals who experienced childhood homelessness were 46.9 times more likely than others to also experience adult homelessness. Testing the hierarchical hypothesis, compared with those who were never homeless, individuals who experienced homelessness only as children reported numerous associated disadvantages, including childhood sexual abuse/neglect, parental adversities, adult incarceration, psychiatric disorders, and low academic achievement/employment. Those reporting both child and adult homelessness, in contrast to childhood homelessness alone, additionally met the criteria for multiple substance use disorders, confirming our hierarchical hypothesis. Those reporting both child and adult homelessness also showed more numerous social and psychiatric problems when compared with those experiencing homelessness for the first time as adults. This study demonstrates how homelessness in childhood is associated with extensive social and psychiatric adversities in both childhood and adulthood.

Abstract A human IgM Ab, serum-derived human IgM 12 (sHIgM12), is identified that binds mouse and human dendritic cells (DC), inducing dramatic immunopotentiation following treatment of the mouse DC in vitro. Competition, transfection, and knockout studies identified the ligand on mouse DC as the costimulatory molecule family member B7-DC. Potent T cell responses are stimulated by Ag-pulsed DC treated with the sHIgM12 Ab in vitro and upon adoptive transfer of Ab-treated Ag-pulsed DC into animals. The multivalent structure of pentameric IgM provides the potential for cross-linking cell surface targets, endowing the soluble Abs with biological potential not normally associated with immune function. The ability of the sHIgM12 Ab to potentiate the immune response is dependent on the multimeric structure of IgM, as bivalent monomers do not retain this property. Furthermore, pretreatment of DC with IgM monomers blocks subsequent potentiation by intact IgM pentamers, an indication that cross-linking of B7-DC on the cell surface is critical for potentiation of Ag presentation. These findings imply that, in addition to known costimulatory roles, B7-DC can function as a receptor for signals delivered by cells expressing B7-DC ligands.