Dynamics of immune responses are inconsistent when trauma patients are grouped by injury severity score and clinical outcomes.

The injury severity score (ISS) is used in daily practice to evaluate the severity of trauma patients; however, the score is not always consistent with the prognosis. After injury, systemic inflammatory response syndrome (SIRS) and compensatory anti-inflammatory response syndrome (CARS) are related to the prognosis of trauma patients. We aimed to evaluate the associations between the immune response and prognosis in trauma patients. Patients who admitted to the Trauma Intensive Care Unit (ICU) were eligible. Whole blood samples were collected at admission, and then 6, 12, 24, 48 and 72 h after admission. Natural killer (NK) cells, lymphocyte subset population and cytokines release were identified using flow cytometry. We grouped patients by their ISS (≤ 25 and > 25 as very severe injury) and ICU stay (≤ 10 days as a short ICU stay and > 10 days as a long ICU stay) for evaluation. Fifty-three patients were enrolled. ICU stay but not ISS was close correlated with activity daily living (ADL) at discharge. Patients with a long ICU stay had an immediate increase in NK cells followed by lymphopenia which persisted for 48 h. Immediate activation of CD8+ T cells and then exhaustion with a higher programmed cell death-1 (PD-1) expression and suppression of CD4+ T cells with a shift to an anti-inflammatory Th2 phenotype were also observed in the patients with a long ICU stay. When the patients were grouped by ISS, the dynamics of immune responses were inconsistent to those when the patients were grouped by ICU stay. Immune responses are associated with the prognosis of trauma patients, however the currently used clinical parameters may not accurately reflect immune responses. Further investigations are needed to identify accurate predictors of prognosis in trauma patients.

Dynamics of cellular immune responses in recipients of renal allografts positive for hepatitis B surface antigen.

BACKGROUND/PURPOSE: Hepatitis B surface antigen (HBsAg)-positive renal transplantation recipients must take lifelong immunosuppressants and nucleotide analogues (NAs). We investigated the cellular immune responses of HBsAg-positive renal transplantation recipients taking immunosuppressants and NAs. METHODS: Blood samples were collected from HBsAg-positive individuals with end-stage renal disease on the transplant waiting list (Group 1) and renal transplantation recipients taking immunosuppressants and NAs (Group 2) or immunosuppressants without NAs (Group 3). Hepatitis B virus (HBV)-specific pentamers were used to quantify circulating HBV-specific CD8+ T cells. RESULTS: Groups 2 and 3 had higher cellular immune responses, as indicated by significantly lower regulatory T (Treg)/CD8+ T cell ratios than Group 1. With undetectable viral loads under both immunosuppressant and NAs, the CD8+ T cell and HBV-specific CD8+ T cell frequencies were similar in Group 2 and Group 1. Patients in Group 3 did not use NAs and had an elevated viral load and higher HBV-specific CD8+ T cell and IFN-γ-producing HBV-specific CD8+ T cell frequencies, but lower a frequency of programmed death-1 (PD-1)+ HBV-specific CD8+ T cells than the other groups. Increased viral replication in Group 3 resulted in significantly higher CD8+ T cell and IFN-γ-producing CD8+ T cell frequencies than Group 1. CONCLUSION: Immunosuppressant therapy increases viral replication in HBsAg-positive renal transplant recipients due to disabling or dysregulation of virus-specific CD8+ T cells. The higher cellular immune responses due to lower Treg/CD8+ T cell ratios in HBsAg-positive renal transplant recipients may be one of the reasons to induce liver pathology because of uncontrolled viral replication.

Adaptive responses to glucose restriction enhance cell survival, antioxidant capability, and autophagy of the protozoan parasite Trichomonas vaginalis.

BACKGROUND: To establish an infection in the vagina, Trichomonas vaginalis must adapt to various environmental cues for survival and further replication. Nutrient competition by lactobacilli, the major normal vaginal flora, is one of the mechanisms to limit the growth of other microorganisms. Additionally, lactobacilli produce H2O2 that can reduce the genital infections caused by other pathogens. Thus, the ability to overcome the metabolic stresses, such as glucose restriction (GR), as well as the oxidative stresses, is critical for T. vaginalis to establish an infection. METHODS: To gain insights into the molecular mechanisms of adaptation to GR, we utilized next-generation RNA sequencing (RNA-seq) to quantify the gene expression changes upon GR. Autophagy, a cytoprotective response to starvation, was monitored by using autophagy-specific staining, autophagy inhibition assay, and co-localization of autophagosomes with lysosomes. RESULTS: We demonstrated that GR promotes the survival of T. vaginalis. Besides, GR-cultivated cells exhibit higher H2O2 resistance. Our RNA-seq data revealed that genes involved in general energy metabolism were downregulated, whereas genes encoding glutamate metabolism-related aminotransferases were strikingly upregulated under GR. Furthermore, autophagy was first identified and characterized in T. vaginalis under GR. CONCLUSIONS: These data suggest that GR induces a metabolic reprogramming, enhancing antioxidant ability and autophagy for cellular homeostasis to maintain survival. GENERAL SIGNIFICANCE: Our work not only led to significant advances in understanding the transcriptional changes in response to GR but also provided possible strategies elicited by GR for T. vaginalis to adapt to the vaginal microenvironment.