Severe Immune Suppression Research Articles

Effective glioblastoma immune sonodynamic treatment mediated by macrophage cell membrane cloaked biomimetic nanomedicines

Glioblastoma (GBM) as one of the most lethal brain tumours, remains poor therapeutic index due to its typical characters including heterogeneous, severe immune suppression as well as the existence of blood brain barrier (BBB). Immune sonodynamic (ISD) therapy combines noninvasive sonodynamic therapy with immunotherapy, which has great prospects for the combinational treatment of GBM. Herein, we develop macrophage cell membrane cloaked reactive oxygen species (ROS) responsive biomimetic nanoparticles, co-delivering of sonosensitizer Ce6 and JQ1 (a bromo-domain protein 4 (BRD4) inhibitor which can down-regulate PD-L1) and realizing potent GBM ISD therapy. The ApoE peptide decorated macrophage membrane coating endows these biomimetic nanoparticles with low immunogenicity, efficient BBB permeability, prolonged blood circulation half-live and good biocompatibility. The ROS responsive polymeric inner core could be readily degraded as triggered by excessive ROS under the ultrasound once they accumulated in tumour cells, fast release encapsulated drugs. The generation of ROS not only killed tumour cells via sonodynamic therapy, but also induced immunogenic cell death (ICD) and further activated the anti-tumour immune response. The released JQ1 inhibited tumour cell proliferation and augmented the immune activities by inhibiting the PD-L1 expression on the surface of tumour cells. The cascade sonodynamic and immune therapy resulted in significantly improved median survival time in both orthotopic GL261 and PTEN deficient immunosuppressive CT2A GBM mice models. Therefore, our developed biomimetic nanoparticle platform provides a promising combinational therapy strategy to treat immune suppressive GBM.

Development and preliminary application of a quadruplex real-time PCR assay for differential detection of porcine circovirus 1-4 in Chengdu, China.

Porcine circovirus (PCV) typically causes severe immune suppression in pigs, leading to mixed clinical infections with various pathogens that can cause significant harm to the pig industry. PCV has four subgenotypes, with PCV4 being an emerging virus that requires investigation due to its potential for epidemic outbreaks. Therefore, there is a need to develop a method that can detect all four PCV strains simultaneously. In this study, four pairs of specific primers and TaqMan probes were designed based on the conserved sequence of the PCV1-4 ORF2 gene to establish a PCV1-4 TaqMan multiplex real-time quantitative PCR method. The novel method was compared to six commercial testing kits for its efficacy. Then, a total of 595 mixed samples of spleen and lymph node collected from 12 districts in Chengdu from July to December 2021 were tested using the novel method. The results showed that the novel PCV1-4 TaqMan multiplex real-time quantitative PCR detection method has satisfied specificity, sensitivity, and repeatability. The positive rates of PCV1, PCV2, and PCV3 in Chengdu were 2.18%, 31.60%, and 15.29%, respectively, while no positive PCV4 was detected. The mixed infection rate of PCV2 and PCV3 was 5.21%. Our novel method may be as a potential method for PCV1-4 detection. Currently, PCV2 is the main epidemic PCV subtype in Chengdu, while the potential threat of PCV4 should also be considered.

Peripheral-central network analysis of cancer cachexia status accompanied by the polarization of hypothalamic microglia with low expression of inhibitory immune checkpoint receptors

While the excessive inflammation in cancer cachexia is well-known to be induced by the overproduction of inflammatory mediators in the periphery, microflora disruption and brain dysfunction are also considered to contribute to the induction of cancer cachexia. Hypothalamic microglia play a crucial role in brain inflammation and central-peripheral immune circuits via the production of inflammatory mediators. In the present study, we evaluated possible changes in excessive secretion of gut microbiota-derived endotoxin and the expression timeline of several inflammation-regulatory mediators and their inhibiting modulators in hypothalamic microglia of a mouse model of cancer cachexia following transplantation of pancreatic cancer cells. We demonstrated that the plasma level of lipopolysaccharide (LPS) was significantly increased with an increase in anaerobic bacteria, especially Firmicutes, in the gut at the late stage of tumor-bearing mice that exhibited dramatic appetite loss, sarcopenia and severe peripheral immune suppression. At the early stage, in which tumor-bearing mice had not yet displayed “cachexia symptoms”, the mRNA expression of pro-inflammatory cytokines, but not of the neurodegenerative and severe inflammatory modulator lipocalin-2 (LCN2), was significantly increased, whereas at the late “cachexia stage”, the level of LCN2 mRNA was significantly increased along with significant decreases in levels of inhibitory immune checkpoint receptors programmed death receptor-1 (PD-1) and CD112R in hypothalamic microglia. In addition, a high density of activated neurons in the paraventricular nucleus (PVN) of the hypothalamus region and a significant increase in corticosterone secretion were found in cachexia model mice. Related to the cachexia state, released corticosterone was clearly increased in normal mice with specific activation of PVN neurons. A marked decrease in the natural killer cell population was also observed in the spleen of mice with robust activation of PVN neurons as well as mice with cancer cachexia. On the other hand, in vivo administration of LPS in normal mice induced hypothalamic microglia with low expression of inhibitory immune checkpoint receptors. These findings suggest that the induction of cancer cachexia may parallel exacerbation of the hypothalamic inflammatory status with polarization to microglia expressed with low levels of inhibitory immune checkpoint receptors following LPS release from the gut microflora.

Severe BCG immune reconstitution inflammatory syndrome lymphadenitis successfully managed with pre-antiretroviral counseling and a non-surgical approach: a case report

BackgroundBacillus Calmette-Guérin (BCG) reactions are the most common cause of immune reconstitution inflammatory syndrome (IRIS) in HIV-positive infants who initiate antiretroviral therapy (ART). There is limited evidence regarding the incidence of BCG-IRIS; however, reports from outpatient cohorts have estimated that 6–9% of infants who initiated ART developed some form of BCG-IRIS within the first 6 months. Various treatment approaches for infants with BCG-IRIS have been reported, but there is currently no widely accepted standard-of-care.Case PresentationA 5-month-old male HIV-exposed infant BCG vaccinated at birth was admitted for refractory oral candidiasis, moderate anemia, and moderate acute malnutrition. He had a HIV DNA-PCR collected at one month of age, but the family never received the results. He was diagnosed with HIV during hospitalization with a point-of-care nucleic acid test and had severe immune suppression with a CD4 of 955 cells/µL (15%) with clinical stage III disease. During pre-ART counseling, the mother was educated on the signs and symptoms of BCG-IRIS and the importance of seeking follow-up care and remaining adherent to ART if symptoms arose. Three weeks after ART initiation, he was readmitted with intermittent subjective fevers, right axillary lymphadenopathy, and an ulcerated papule over the right deltoid region. He was subsequently discharged home with a diagnosis of local BCG-IRIS lymphadenitis. At six weeks post-ART initiation, he returned with suppurative lymphadenitis of the right axillary region that had completely eviscerated through the skin without signs of disseminated BCG disease. He was then started on an outpatient regimen of topical isoniazid, silver nitrate, and oral prednisolone. Throughout this time, the mother maintained good ART adherence despite this complication. After 2.5 months of ART and one month of specific treatment for the lymphadenitis, he had marked mass reduction, improved adenopathy, increased CD4 count, correction of anemia, and resolution of his acute malnutrition. He completely recovered and was symptom free two months after initial treatment without surgical intervention.ConclusionsThis case details the successful management of severe suppurative BCG-IRIS with a non-surgical approach and underlines the importance of pre-ART counseling on BCG-IRIS for caregivers, particularly for infants who initiate ART with advanced HIV.

Radioimmunotherapy as a pathogen-agnostic treatment method for opportunistic mucormycosis infections.

Invasive fungal infections (IFIs) such as mucormycosis are causing devastating morbidity and mortality in immunocompromised patients as anti-fungal agents do not work in the setting of a suppressed immune system. The coronavirus disease 2019 (COVID-19) pandemic has created a novel landscape for IFIs in post-pandemic patients, resulting from severe immune suppression caused by COVID-19 infection, comorbidities (diabetes, obesity) and immunosuppressive treatments such as steroids. The antigen-antibody interaction has been employed in radioimmunotherapy (RIT) to deliver lethal doses of ionizing radiation emitted by radionuclides to targeted cells and has demonstrated efficacy in several cancers. One of the advantages of RIT is its independence of the immune status of a host, which is crucial for immunosuppressed post-COVID-19 patients. In the present work we targeted the fungal pan-antigens 1,3-beta-glucan and melanin pigment, which are present in the majority of pathogenic fungi, with RIT, thus making such targeting pathogen-agnostic. We demonstrated in experimental murine mucormycosis in immunocompetent and immunocompromised mice that lutetium-177 (177Lu)-labelled antibodies to these two antigens effectively decreased the fungal burden in major organs, including the brain. These results are encouraging because they show the effectiveness of pathogen-agnostic RIT in significantly decreasing fungal burden in vivo, while they can also potentially be applied to treat the broad range of invasive fungal infections that express the pan-antigens 1,3-beta-glucan or melanin.

Comprehensive proteomic analysis of JC polyomavirus-infected human astrocytes and their extracellular vesicles.

JC polyomavirus (JCPyV) is an opportunistic virus that remains in a latent state in the kidneys and lymphoid organs of more than half of the human adult population. In rare cases of severe immune suppression, the virus is able to establish a lytic infection of glial cells in the brain, resulting in a debilitating, demyelinating disease known as progressive multifocal leukoencephalopathy (PML). Because of the exceptional species and tissue specificity of the virus, appropriate models of JCPyV infection in the brain are lacking, thus hampering progress toward the development of novel antiviral strategies and biomarkers of disease activity. While PML has traditionally been characterized as a lytic infection of oligodendrocytes, more recent findings suggest an important role for astrocytes during the initial stages of disease. Here, using human-induced pluripotent stem cell (hiPSC)-derived astrocytes coupled with a multiparametric approach, we show that (i) JCPyV readily infects and replicates in astrocytes, (ii) JCPyV strongly dysregulates the cell biology, and (iii) these results adequately reflect ex vivo findings. We perform an in-depth characterization of the effect of JCPyV on the cell proteome over time, demonstrating a strong dysregulation of the cell cycle and activation of the DNA damage response. Furthermore, we show that the proteomic signature observed for infected astrocytes is extended to extracellular vesicles, underlining their potential as a resource to gain valuable insights into JCPyV infection in the brain. IMPORTANCE Progressive multifocal leukoencephalopathy is a crimpling demyelinating disease of the central nervous system caused by JC polyomavirus (JCPyV). Much about JCPyV propagation in the brain remains obscure because of a lack of proper animal models to study the virus in the context of the disease, thus hampering efforts toward the development of new antiviral strategies. Here, having established a robust and representative model of JCPyV infection in human-induced pluripotent stem cell-derived astrocytes, we are able to fully characterize the effect of JCPyV on the biology of the cells and show that the proteomic signature observed for JCPyV-infected astrocytes is extended to extracellular vesicles (EVs). These data suggest that astrocyte-derived EVs found in body fluids might serve as a rich source of information relevant to JCPyV infection in the brain, opening avenues toward better understanding the pathogenesis of the virus and, ultimately, the identification of new antiviral targets.

Upregulation of the NKG2D Ligand ULBP2 by JC Polyomavirus Infection Promotes Immune Recognition by Natural Killer Cells.

JC polyomavirus (JCPyV) causes progressive multifocal leukoencephalopathy (PML), a potentially fatal complication of severe immune suppression with no effective treatment. Natural killer (NK) cells play critical roles in defense against viral infections; however, NK-cell response to JCPyV infection remains unexplored. NK- and T-cell responses against the JCPyV VP1 were compared using intracellular cytokine staining upon stimulation with peptide pools. A novel flow cytometry-based assay was developed to determine NK-cell killing efficiency of JCPyV-infected astrocyte-derived SVG-A cells. Blocking antibodies were used to evaluate the contribution of NK-cell receptors in immune recognition of JCPyV-infected cells. In about 40% of healthy donors, we detected robust CD107a upregulation and IFN-γ production by NK cells, extending beyond T-cell responses. Next, using the NK-cell-mediated killing assay, we showed that coculture of NK cells and JCPyV-infected SVG-A cells leads to a 60% reduction in infection, on average. JCPyV-infected cells had enhanced expression of ULBP2-a ligand for the activating NK-cell receptor NKG2D, and addition of NKG2D blocking antibodies decreased NK-cell degranulation. NKG2D-mediated activation of NK cells plays a key role in controlling JCPyV replication and may be a promising immunotherapeutic target to boost NK-cell anti-JCPyV activity.

A Case of Progressive Multifocal Leucoencephalopathy and Cerebral Toxoplasmosis in an HIV-Infected Patient

Abstract Progressive multifocal leukoencephalopathy (PML) is an opportunistic infection of the central nervous system (CNS) caused by the reactivation of John Cunningham polyomavirus (JCV). Most often, this disease is observed in patients with severe immune suppression, such as those with AIDS. Cerebral toxoplasmosis results from the reactivation of a latent infection with Toxoplasma gondii, an intracellular parasite. This parasitosis is relatively rare in the United States, while in some regions of Europe the seropositive population is over 90%. Similarly, to PML, cerebral toxoplasmosis develops in stages of advanced immune deficiency. Both of these opportunistic infections of the central nervous system can cause severe neurological symptoms, and their simultaneous presentation can represent a diagnostic and therapeutic problem. We present a case of a 59-year-old patient with a newly diagnosed HIV infection with manifestations of epilepsy and progressive cognitive impairment. The patient was diagnosed initially with cerebral toxoplasmosis and subsequently with progressive multifocal leukoencephalopathy.

A brief report on eugenol oleate is an oral immunomodulatory molecule against visceral leishmaniasis

Visceral Leishmaniasis (VL) is a life-threatening infectious disease and is acclaimed as a neglected tropical disease, caused by Leishmania donovani. It leads to severe immune suppression in the host defense system. Higher cytotoxicity, rigorous side effects, and lower therapeutic indexes (TI) of current antileishmanial drugs have created a necessity to develop new molecules with better antileishmanial activity and high TI value. We synthesized a plenty number of derivatives of Eugenol and screened them for their activity against promastigote and amastigote forms of L. donovani. Among the synthesized derivatives, Eugenol oleate showed better antileishmanial activity against extracellular promastigotes (IC50- 20.13 ± 0.91 μM) and intracellular amastigotes (EC50-4.25 ± 0.26 μM). The TI value (82.24 ± 3.77) was found to improve by 10 to 13-folds compared to amphotericin B and miltefosine, respectively. Treatment with Eugenol oleate activated the PKC-βII–p38 MAPK and produced IL-12 and IFN-γ, which activated the iNOS2 to produce NO free radicals that cleared the intracellular parasite. Eugenol oleate was found safe with an appreciable pharmacokinetic profile for the oral anti-VL agent. This molecule increased the Th1 cytokine profile and decreased the Th2 cytokine profile observed from ELISA and qPCR, suggesting that the Eugenol oleate induced the parasite clearance through the activation of the host immune system. Hence, this study represented that Eugenol oleate, an oral immunomodulatory molecule, could induce a host protective immune response against visceral leishmaniasis through enhanced NO generation and Th1 response, essential against this deadly disease.

Elucidating the role played by the NKG2 family of receptors in natural killer cell responses to JC polyomavirus

Abstract JC polyomavirus (JCPyV) causes progressive multifocal leukoencephalopathy (PML), a potentially fatal complication of severe immune suppression due to monoclonal antibody treatments for cancer, autoimmune diseases and transplantation, or due to uncontrolled HIV infection. There is currently no effective treatment against PML and novel immunotherapies are urgently needed. Natural killer (NK) cells play critical roles in defense against viral infections, yet NK cell responses to JCPyV remain largely unexplored. Here, we first compared NK and T cell responses against JCPyV VP1 peptide pools by intracellular cytokine staining. In about 40% of healthy donors, we detected robust CD107a upregulation and IFNγ production by NK cells, extending beyond T cell responses. Next, using a novel flow cytometry-based killing assay, we showed that co-culture of NK cells and JCPyV-infected SVG-A cells led to a 65% reduction in infection, on average. To identify receptor-ligand interactions modulating NK cell-mediated responses to JCPyV, we performed co-cultures in the presence of select blocking antibodies. We observed enhanced expression of ligands for the activating NKG2D on infected cells and accordingly, NKG2D blockade resulted in decreased NK cell degranulation. In contrast, blockade of inhibitory NKG2A enhanced NK cell response to JCPyV-infected targets. Moreover, we identified JCPyV-derived peptides that elicit dominant NK cell responses and can stabilize HLA-E, the ligand for NKG2A and the activating NKG2C. Altogether, these findings suggest that modulation of NKG2D and NKG2A/C signaling may play key roles in NK cell-mediated control of JCPyV and may be promising immunotherapeutic targets to boost NK cell anti-JCPyV activity. Supported by grant from NIH (R01 NS116278)

Ongoing High Prevalence of Severe Immune Suppression Among Children in South Africa.

Among children in Southern Africa severe immune suppression (SIS) has declined, but most continue to initiate antiretroviral therapy (ART) with SIS. Using data from South Africa, we describe SIS at ART start and on ART between 2007 and 2020, among children <5 years with a CD4%/cell count at ART start and ≥1 subsequent measure. Gap in care was defined as >9 months without a recorded visit. We defined SIS according to age and CD4%/cell count. A multistate model was used to estimate transition probabilities between 5 states: SIS on ART; Stable, not SIS; Early Gap, commencing <9 months from ART start; Late Gap, commencing ≥9 months on ART; and Death. Among 2536 children, 70% had SIS at ART start, and 36% experienced SIS on ART. An increasing proportion were age <1 year at ART initiation (2007-2009: 43% to 2013-2020: 55%). Increasingly, SIS on ART occurred after a gap, in those with SIS on ART for >1 year, and after a period of unknown immune status. Later year of ART initiation was associated with reduced transition from SIS on ART to Stable. Infants and those initiating ART with SIS were more likely to transition from Stable to SIS. Viremia strongly predicted death from both the on ART states. Increasingly SIS occurred among ART-experienced children. Those starting ART with SIS and during infancy remained especially vulnerable to SIS once on treatment. Managing ART in these children may be more complex and further reducing AIDS-related mortality is likely to remain challenging.

A Clinical Update on SARS-CoV-2: Pathology and Development of Potential Inhibitors.

SARS-CoV-2 (severe acute respiratory syndrome) is highly infectious and causes severe acute respiratory distress syndrome (SARD), immune suppression, and multi-organ failure. For SARS-CoV-2, only supportive treatment options are available, such as oxygen supportive therapy, ventilator support, antibiotics for secondary infections, mineral and fluid treatment, and a significant subset of repurposed effective drugs. Viral targeted inhibitors are the most suitable molecules, such as ACE2 (angiotensin-converting enzyme-2) and RBD (receptor-binding domain) protein-based inhibitors, inhibitors of host proteases, inhibitors of viral proteases 3CLpro (3C-like proteinase) and PLpro (papain-like protease), inhibitors of replicative enzymes, inhibitors of viral attachment of SARS-CoV-2 to the ACE2 receptor and TMPRSS2 (transmembrane serine proteinase 2), inhibitors of HR1 (Heptad Repeat 1)-HR2 (Heptad Repeat 2) interaction at the S2 protein of the coronavirus, etc. Targeting the cathepsin L proteinase, peptide analogues, monoclonal antibodies, and protein chimaeras as RBD inhibitors interferes with the spike protein's ability to fuse to the membrane. Targeting the cathepsin L proteinase, peptide analogues, monoclonal antibodies, and protein chimaeras as RBD inhibitors interferes with the spike protein's ability to fuse to the membrane. Even with the tremendous progress made, creating effective drugs remains difficult. To develop COVID-19 treatment alternatives, clinical studies are examining a variety of therapy categories, including antibodies, antivirals, cell-based therapy, repurposed diagnostic medicines, and more. In this article, we discuss recent clinical updates on SARS-CoV-2 infection, clinical characteristics, diagnosis, immunopathology, the new emergence of variant, SARS-CoV-2, various approaches to drug development and treatment options. The development of therapies has been complicated by the global occurrence of many SARS-CoV-2 mutations. Discussion of this manuscript will provide new insight into drug pathophysiology and drug development.

IMMU-36. EVALUATION OF TUMOR DERIVED SERPINA3N IN EXPERIMENTAL GLIOBLASTOMA

Abstract Glioblastoma (GBM) is an incurable brain cancer which is associated with severe peripheral immune suppression. Using experimental GBM, we recently determined that peripheral immunosuppression involves thymic atrophy, stunted T cell proliferation, and release of circulating factors that inhibit immune responses. RNA sequencing and proteomic studies have determined that transcripts and protein levels of Serpina3n are upregulated in the brain and serum of GBM patients and correlates with poor prognosis. We determined Serpina3n is a highly upregulated gene in the brain and the thymus of glioma-bearing mice using RNA sequencing technologies. Proteomic analysis of serum from glioma-bearing mice identified an upregulation of pathways associated with the extracellular expression of Serpina3n. We therefore sought to determine the role of Serpina3n in peripheral immunosuppression in GL261 glioma harboring wild type and Serpina3n knockout mice. Glioma implantation in Serpina3n knockout mice resulted in similar survival and peripheral immunosuppression compared to controls. Western blotting experiments confirmed that Serpina3n is expressed and secreted by GL261 gliomas isolated from WT and Serpina3n knockout mouse brains. Together this data suggests that tumor-derived, but not host derived, Serpina3n needs to be evaluated as a putative factor associated with peripheral immunosuppression.

Analysis of Severe Illness After Postvaccination COVID-19 Breakthrough Among Adults With and Without HIV in the US

Understanding the severity of postvaccination SARS-CoV-2 (ie, COVID-19) breakthrough illness among people with HIV (PWH) can inform vaccine guidelines and risk-reduction recommendations. To estimate the rate and risk of severe breakthrough illness among vaccinated PWH and people without HIV (PWoH) who experience a breakthrough infection. In this cohort study, the Corona-Infectious-Virus Epidemiology Team (CIVET-II) collaboration included adults (aged ≥18 years) with HIV who were receiving care and were fully vaccinated by June 30, 2021, along with PWoH matched according to date fully vaccinated, age group, race, ethnicity, and sex from 4 US integrated health systems and academic centers. Those with postvaccination COVID-19 breakthrough before December 31, 2021, were eligible. HIV infection. The main outcome was severe COVID-19 breakthrough illness, defined as hospitalization within 28 days after a breakthrough SARS-CoV-2 infection with a primary or secondary COVID-19 discharge diagnosis. Discrete time proportional hazards models estimated adjusted hazard ratios (aHRs) and 95% CIs of severe breakthrough illness within 28 days of breakthrough COVID-19 by HIV status adjusting for demographic variables, COVID-19 vaccine type, and clinical factors. The proportion of patients who received mechanical ventilation or died was compared by HIV status. Among 3649 patients with breakthrough COVID-19 (1241 PWH and 2408 PWoH), most were aged 55 years or older (2182 patients [59.8%]) and male (3244 patients [88.9%]). The cumulative incidence of severe illness in the first 28 days was low and comparable between PWoH and PWH (7.3% vs 6.7%; risk difference, -0.67%; 95% CI, -2.58% to 1.23%). The risk of severe breakthrough illness was 59% higher in PWH with CD4 cell counts less than 350 cells/μL compared with PWoH (aHR, 1.59; 95% CI, 0.99 to 2.46; P = .049). In multivariable analyses among PWH, being female, older, having a cancer diagnosis, and lower CD4 cell count were associated with increased risk of severe breakthrough illness, whereas previous COVID-19 was associated with reduced risk. Among 249 hospitalized patients, 24 (9.6%) were mechanically ventilated and 20 (8.0%) died, with no difference by HIV status. In this cohort study, the risk of severe COVID-19 breakthrough illness within 28 days of a breakthrough infection was low among vaccinated PWH and PWoH. PWH with moderate or severe immune suppression had a higher risk of severe breakthrough infection and should be included in groups prioritized for additional vaccine doses and risk-reduction strategies.

T cell receptor β-chain-targeting chimeric antigen receptor T cells against T cell malignancies

The success of chimeric antigen receptor (CAR) T cells in treating B cell malignancies comes at the price of eradicating normal B cells. Even though T cell malignancies are aggressive and treatment options are limited, similar strategies for T cell malignancies are constrained by the severe immune suppression arising from bystander T cell aplasia. Here, we show the selective killing of malignant T cells without affecting normal T cell-mediated immune responses in vitro and in a mouse model of disseminated leukemia. Further, we develop a CAR construct that carries the single chain variable fragment of a subtype-specific antibody against the variable TCR β-chain region. We demonstrate that these anti-Vβ8 CAR-T cells are able to recognize and kill all Vβ8+ malignant T cells that arise from clonal expansion while sparing malignant or healthy Vβ8− T cells, allowing sufficient T cell-mediated cellular immunity. In summary, we present a proof of concept for a selective CAR-T cell therapy to eradicate T cell malignancies while maintaining functional adaptive immunity, which opens the possibility for clinical development.

Altered white matter microstructure and neurocognitive function of HIV-infected patients with low nadir CD4.

Altered white matter microstructure has been reported repeatedly using diffusion tensor imaging (DTI) in HIV-associated neurocognitive disorders. However, the associations between neurocognitive deficits and impaired white matter remains obscure due to frequent physical and psychiatric comorbidities in the patients. Severe immune suppression, reflected by low nadir CD4 T-cell counts, is reported to be associated with the neurocognitive deficits in the patients. In the present study, we examined white matter integrity using DTI and tract-based spatial statistics (TBSS), and neurocognitive functions using a battery of tests, in 15 HIV-infected patients with low nadir CD4, 16 HIV-infected patients with high nadir CD4, and 33 age- and sex-matched healthy controls. As DTI measures, we analyzed fractional anisotropy (FA) and mean diffusivity (MD). In addition, we investigated the correlation between white matter impairments and neurocognitive deficits. Among the three participant groups, the patients with low nadir CD4 showed significantly lower performance in processing speed and motor skills, and had significantly increased MD in widespread regions of white matter in both hemispheres. In the patients with low nadir CD4, there was a significant negative correlation between motor skills and MD in the right motor tracts, as well as in the corpus callosum. In summary, this study may provide white matter correlates of neurocognitive deficits in HIV-infected patients with past severe immune suppression as legacy effects.

Halofuginone micelle nanoparticles eradicate Nrf2-activated lung adenocarcinoma without systemic toxicity

The Keap1-Nrf2 system is the master regulator of the cellular response against oxidative and xenobiotic stresses. Constitutive activation of Nrf2 is frequently observed in various types of cancers. Nrf2 hyperactivation induces metabolic reprogramming in cancer cells, which supports the increased energy demand required for rapid proliferation and confers high-level resistance against anticancer radio/chemotherapy. Hence, Nrf2 inhibition has emerged as an attractive therapeutic strategy to counter such acquired resistance in Nrf2-activated tumors. We previously identified Halofuginone (HF) as a promising Nrf2 inhibitor. In this study, we pursued preclinical characterization of HF and found that while HF markedly reduced the viability of cancer cells, it also caused severe hematopoietic and immune cell suppression in a dose-dependent manner. Hence, to overcome this toxicity, we decided to employ a nanomedicine approach to HF. We found that encapsulation of HF into a polymeric micelle (HF micelle; HFm) largely relieved the systemic toxicity exhibited by free HF while maintaining the tumor-suppressive properties of HF. LC-MS/MS analysis revealed that the reduction in the magnitude of adverse effects was the result of the ability to release HF from the HFm core in a slow and sustained manner. These results thus support the contention that HFm will potentially counteract Nrf2-activated cancers in the clinical settings.

Evaluation of tumor derived Serpina3n in experimental glioblastoma

Abstract Glioblastoma (GBM) is an incurable brain cancer which is associated with severe peripheral immune suppression. Using experimental GBM, we recently determined that peripheral immunosuppression involves thymic atrophy, stunted T cell proliferation, and release of circulating factors that inhibit immune responses. RNA sequencing and proteomic studies have recently determined that transcripts and protein levels of Serpina3n are upregulated in the brain and serum of GBM patients and correlates with poor prognosis. We determined Serpina3n is a highly upregulated gene in the brain and the thymus of glioma-bearing mice using RNA sequencing technologies. We therefore sought to determine the role of Serpina3n in peripheral immunosuppression in GL261 glioma harboring wild type and Serpina3n knockout mice. Glioma implantation in Serpina3n knockout mice resulted in similar survival and peripheral immunosuppression compared to controls. Western blotting experiments confirmed that Serpina3n is expressed and secreted by GL261 gliomas isolated from WT and Serpina3n knockout mouse brains. Together this data suggests that tumor-derived, but not host derived, Serpina3n needs to be evaluated as a putative factor associated with peripheral immunosuppression. Supported by Brains Together for a Cure grant

Interactions of Muscovy duck reovirus, gut microbiota, and host innate immunity: Transcriptome and gut microbiota analysis

It has been shown that Muscovy duck reovirus (MDRV) infection causes severe intestinal barrier damage and intestinal mucosal immune suppression. The health and balance of gut microbes is essential for the progression of intestinal infectious diseases. To investigate the interaction of MDRV, intestinal bacteria with host intestinal innate immunity, an MDRV contact-infection model was established in this study. High-throughput sequencing technology was used to sequence 16S rDNA and transcripts in ileal samples from experimental Muscovy ducklings. Our results suggest that intestinal opportunistic pathogens such as Streptococcus and Corynebacterium proliferated massively in MDRV-infected Muscovy ducklings. The body initiates antiviral and antibacterial immunity and actively fights the infection of gut microbes. The synthesis of peptidoglycan, lipopolysaccharide, and flagellin by intestinal bacteria activates the Toll-like receptor signaling pathway resulting in increased secretion of IFN-β, IL-1β, and IL-8. The RIG-I-like receptor signaling pathway is an important signaling pathway for the interaction between MDRV and the host. At the same time, we also observed that multiple genes in the JAK-STAT signaling pathway were significantly different. These genes are important targets for studying the immunosuppression caused by MDRV. In conclusion, we analyzed the interaction of MDRV, intestinal flora and host immune system during MDRV infection, which provides a basis for the further study on the mechanism of intestinal immunosuppression caused by MDRV.

Severe Adaptive Immune Suppression May Be Why Patients With Severe COVID-19 Cannot Be Discharged From the ICU Even After Negative Viral Tests.

During the COVID-19 pandemic, a phenomenon emerged in which some patients with severe disease were critically ill and could not be discharged from the ICU even though they exhibited negative viral tests. To explore the underlying mechanism, we collected blood samples from these patients and analyzed the gene expression profiles of peripheral immune cells. We found that all enrolled patients, regardless of changes in genes related to different symptoms and inflammatory responses, showed universally and severely decreased expression of adaptive immunity-related genes, especially those related to T/B cell arms and HLA molecules, and that these patients exhibited long-term secondary infections. In addition, no significant change was found in the expression of classic immunosuppression molecules including PD-1, PD-L1, and CTLA-4, suggesting that the adaptive immune suppression may not be due to the change of these genes. According to the published literatures and our data, this adaptive immunosuppression is likely to be caused by the “dysregulated host response” to severe infection, similar to the immunosuppression that exists in other severely infected patients with sepsis.