Common and Exclusive Features of Intestinal Intraepithelial γδ T Cells and Other γδ T Cell Subsets.

Murine peripheral lymph node TCR γδ T cells have been divided into type 1 and type 17 functional categories based on phenotypic and functional markers. Localized in the gut epithelial barrier, intestinal intraepithelial lymphocytes (iIEL) γδ T cells constitute a peculiar subset of T lymphocytes involved in intestinal homeostasis. However, whether iIEL γδ T cells obey the type 1/type 17 dichotomy is unclear. Using both global transcriptional signatures and expression of cell surface markers, we reveal that murine iIEL γδ T cells compose a distinct population, expressing ∼1000 specific genes, in particular genes that are responsible for cytotoxicity and regulatory functions. The expression of the transcription factor Helios is a feature of iIEL γδ T cells, distinguishing them from the other TCR γδ T subsets, including those present in the epithelia of other tissues. The marked expression of Helios is also shared by the other iIELs, TCRαßCD8αα lymphocytes present within the intestinal epithelium. Finally, we show that Helios expression depends in part on TGF-ß signaling but not on the microbiota. Thus, our study proposes iIEL γδ T cells as a distinct subset and identifies novel markers to differentiate them from their peripheral counterparts.

Prevalence of HIV Viral Load Suppression Among Psychiatric Inpatients with Comorbid Substance Use Disorders.

A consistently suppressed viral load enables HIV (+) patients to live longer, healthier lives and reduces the probability of transmitting the virus. Since the prevalence of HIV is four times higher among those with psychiatric disorders than in the general population, it is likely that this group would also have greater difficulty remaining in care and achieving viral suppression. A secondary data analysis utilizing screening data from the Preventing AIDS Through Health (PATH) for Triples (PFT) Study were examined to assess HIV load suppression among 254 psychiatric inpatients with comorbid substance use disorders in Philadelphia. Viral load results from the past 12 months were obtained from medical records for 63 inpatients identified as HIV (+). The sample was predominately African American (76%), male (56%), and the average age was 43 years. Psychiatric disorders included depression (64%), schizophrenia (21%), and bipolar disorder (13%) with patients reporting use of alcohol (73%), cocaine (64%), cannabis (29%) and opioids (16%) prior to admission. Among this high risk sample of HIV (+) patients, about one-half (52%) achieved viral suppression, with recent opioid users six times more likely to have a detectable viral load than non-opioid users (OR 6.0; CI 1.1-31.7, p = .035). The 52% viral load suppression rate among psychiatric inpatient was higher than expected, given that the CDC's national suppression rate among those diagnosed with HIV in the general population is 58%. However, individuals with mental illness and substance use disorders require constant surveillance, monitoring, and supportive services to achieve viral suppression. Many of those who were virally suppressed were engaged in Philadelphia's extensive treatment network, whereas those who were detectable and enrolled in the PFT intervention were often homeless with unstable psychiatric symptoms and current substance use disorders, particularly opioid abuse.