SOCS1 and SOCS3 are expressed in mononuclear cells in human cytomegalovirus viremia after allogeneic hematopoietic stem cell transplantation

Chronic inflammation degrades CD4 T cell immunity to prior vaccines in treated HIV infection

To date, our understanding of how HIV infection impacts vaccine-induced cellular immunity is limited. Here, we investigate inflammation, immune activation and antigen-specific T cell responses in HIV-uninfected and antiretroviral-treated HIV-infected people. Our findings highlight lower recall responses of antigen-specific CD4 T cells that correlate with high plasma cytokines levels, T cell hyperactivation and an altered composition of the T subsets enriched with more differentiated cells in the HIV-infected group. Transcriptomic analysis reveals that antigen-specific CD4 T cells of the HIV-infected group have a reduced expression of gene sets previously reported to correlate with vaccine-induced pathogen-specific protective immunity and further identifies a consistent impairment of the IFNα and IFNγ response pathways as mechanism for the functional loss of recall CD4 T cell responses in antiretroviral-treated people. Lastly, in vitro treatment with drugs that reduce inflammation results in higher memory CD4 T cell IFNγ responses. Together, our findings suggest that vaccine-induced cellular immunity may benefit from strategies to counteract inflammation in HIV infection.

Distinct Repopulation Activity in Hu-Mice Between CB- and LPB-CD34＋ Cells by Enrichment of Transcription Factors

Background and Objectives

Human CD34^＋ hematopoietic stem cells can reconstitute the human hematopoietic system when transplanted into immunocompromised mice after irradiation. Human leukapheresis peripheral blood (LPB)- and cord blood (CB)-derived CD34^＋ cells have a similar capacity to reconstitute myeloid lineage cells in a humanized mice (hu-mice) model. However, potent stem cells, such as CB-CD34^＋ cells, efficiently reconstitute the lymphoid system in vivo compared to LPB-CD34^＋ cells. Modeling the human hematolymphoid system is vital for studying immune cell crosstalk in human xenografted mice, with CB-CD34^＋ cells used as an optimized cell source because they are essential in reconstituting lymphoid lineage cells.

Methods and Results

In this study, we established hu-mice that combined human characteristics with long-term survival and investigated the efficiency of the engraftment of lymphoid lineage cells derived from LPB- and CB-CD34^＋ cells in the bone marrow, spleen, and LPB. We found an overall increase in the transcriptional activity of lymphoid lineage genes in CB-CD34^＋ cells. Our results revealed that potent CB-CD34^＋ cells displaying a general upregulation of the expression of genes involved in lymphopoiesis could contribute to the hematolymphoid system in the humanized mice model with longevity.

Conclusions

Our data suggest that humanized mouse model by usage of CB-CD34^＋ cells displaying high expression of TFs for lymphoid lineage cells can contribute to study the immune response against lymphocytes.

Human cytomegalovirus infection: A considerable issue following allogeneic hematopoietic stem cell transplantation

Cytomegalovirus (CMV) is an opportunistic virus, whereby recipients are most susceptible following allogeneic hematopoietic stem cell transplantation (allo-HSCT). With the development of novel immunosuppressive agents and antiviral drugs, accompanied with the widespread application of prophylaxis and preemptive treatment, significant developments have been made in transplant recipients with human (H)CMV infection. However, HCMV remains an important cause of short- and long-term morbidity and mortality in transplant recipients. The present review summarizes the molecular mechanism and risk factors of HCMV reactivation following allo-HSCT, the diagnosis of CMV infection following allo-HSCT, prophylaxis and treatment of HCMV infection, and future perspectives. All relevant literature were retrieved from PubMed and have been reviewed.

Cytomegalovirus Infections after Hematopoietic Stem Cell Transplantation: Current Status and Future Immunotherapy

Cytomegalovirus (CMV) infection after hematopoietic stem cell transplantation (HSCT) is one of the critical infectious complications related to host immune recovery. The spectrum of CMV infection is quite extensive, from asymptomatic CMV reactivation presenting mainly as CMV DNAemia to fatal CMV diseases involving gut, liver, lungs, or brain. In addition to organ involvement, CMV reactivation can exert indirect effects such as immunosuppression or graft failure that may result in the development of concurrent infectious complications. Currently, preemptive therapy, which is based on PCR-based monitoring of CMV from blood, is a mainstay enabling improvement in CMV-related outcomes. During the past decades, new antiviral drugs, clinical trials for prophylaxis in high-risk groups, and vaccines for preventing CMV infection have been introduced. In addition, data for immunologic monitoring and adoptive immunotherapy have also been accumulated. Here, we review the current status and recent updates in this field, with future perspectives including immunotherapy in HSCT recipients.

SOCS molecules: the growing players in macrophage polarization and function

The concept of macrophage polarization is defined in terms of macrophage phenotypic heterogeneity and functional diversity. Cytokines signals are thought to be required for the polarization of macrophage populations toward different phenotypes at different stages in development, homeostasis and disease. The suppressors of cytokine signaling family of proteins contribute to the magnitude and duration of cytokines signaling, which ultimately control the subtle adjustment of the balance between divergent macrophage phenotypes. This review highlights the specific roles and mechanisms of various cytokines family and their negative regulators link to the macrophage polarization programs. Eventually, breakthrough in the identification of these molecules will provide the novel therapeutic approaches for a host of diseases by targeting macrophage phenotypic shift.