Protocol to examine murine visceral adipose tissue immune cells using fluorescence-based flow cytometry.

Adipose tissue immune cells are heterogeneous and dynamic, alter metabolism, and drive immune responses. Here, we present a protocol for assessment and characterization of murine adipose tissue immune cells using fluorescence-based flow cytometry and sorting into pure populations. We describe steps for isolation of the stromovascular fraction, antibody staining, and data collection by flow cytometry. We also discuss common issues and troubleshooting steps. For complete details on the use and execution of this protocol, please refer to Carey et al.1.

Age-associated accumulation of B cells promotes macrophage inflammation and inhibits lipolysis in adipose tissue during sepsis.

Non-canonical lipolysis induced by inflammatory cytokines or Toll-like receptor ligands is required for the regulation of inflammation during endotoxemia and sepsis. Canonical lipolysis induced by catecholamines declines during aging due to factors including an expansion of lymphocytes, pro-inflammatory macrophage polarization, and an increase in chronic low-grade inflammation; however, the extent to which the non-canonical pathway of lipolysis is active and impacted by immune cells during aging remains unclear. Therefore, we aimed to define the extent to which immune cells from old mice influence non-canonical lipolysis during sepsis. We identified age-associated impairments of non-canonical lipolysis and an accumulation of dysfunctional B1 B cells in the visceral white adipose tissue (vWAT) of old mice. Lifelong deficiency of B cells results in restored non-canonical lipolysis and reductions in pro-inflammatory macrophage populations. Our study suggests that targeting the B cell-macrophage signaling axis may resolve metabolic dysfunction in aged vWAT and attenuate septic severity in older individuals.

A new standard of sexual behavior? Are claims associated with the "hookup culture" supported by general social survey data?

Popular media have described intimate relationships among contemporary college students as dominated by a pervasive sexual "hookup culture," implying that students are involved in frequent sexual encounters pursued by both participants without the expectation of a continuing relationship. The hookup culture has been described as "a nationwide phenomenon that has largely replaced traditional dating on college campuses" (Bogle, 2008 , p. 5). We tested whether these claims are supported among young adults (18-25) who had completed at least one year of college. Contrasting 1988-1996 waves of the General Social Survey with 2004-2012 waves, we found respondents from the current era did not report more sexual partners since age 18, more frequent sex, or more partners during the past year than respondents from the earlier era. Sexually active respondents from the current era were more likely than those from the earlier era to report sex with a casual date/pickup or friend, and less likely to report sex with a spouse/regular partner. These modest changes are consistent with cultural shifts in the "scripts" and terminology surrounding sexuality. We find no evidence of substantial changes in sexual behavior that would indicate a new or pervasive pattern of non-relational sex among contemporary college students.