scholarly journals Reduced development of COVID-19 in children reveals molecular checkpoints gating pathogenesis illuminating potential therapeutics

2020 ◽  
Vol 117 (40) ◽  
pp. 24620-24626 ◽  
Author(s):  
Jonathan Baruch Steinman ◽  
Fok Moon Lum ◽  
Peggy Pui-Kay Ho ◽  
Naftali Kaminski ◽  
Lawrence Steinman
Keyword(s):  
Severe Acute Respiratory Syndrome ◽  
Immune Responses ◽  
Respiratory Tract ◽  
Global Economy ◽  
T Cell Immunity ◽  
T Helper ◽  
T Helper 2 ◽  
Cell Immunity ◽  
The Impact ◽  
Potential Therapeutics

The reduced development of COVID-19 for children compared to adults provides some tantalizing clues on the pathogenesis and transmissibility of this pandemic virus. First, ACE2, the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) receptor, is reduced in the respiratory tract in children. Second, coronavirus associated with common colds in children may offer some protection, due to cross-reactive humoral immunity and T cell immunity between common coronaviruses and SARS-CoV-2. Third, T helper 2 immune responses are protective in children. Fourth, surprisingly, eosinophilia, associated with T helper 2, may be protective. Fifth, children generally produce lower levels of inflammatory cytokines. Finally, the influence of the downturn in the global economy, the impact of living in quarters among families who are the most at risk, and factors including the openings of some schools, are considered. Those most disadvantaged socioeconomically may suffer disproportionately with COVID-19.

scholarly journals T Cell Immunity against Influenza: The Long Way from Animal Models Towards a Real-Life Universal Flu Vaccine

Viruses ◽  
2021 ◽  
Vol 13 (2) ◽  
pp. 199
Author(s):  
Anna Schmidt ◽  
Dennis Lapuente
Keyword(s):  
T Cells ◽  
T Cell ◽  
Animal Models ◽  
Respiratory Tract ◽  
Memory T Cells ◽  
Real Life ◽  
T Cell Immunity ◽  
Cell Immunity ◽  
Flu Vaccine ◽  
Resident Memory T Cells

Current flu vaccines rely on the induction of strain-specific neutralizing antibodies, which leaves the population vulnerable to drifted seasonal or newly emerged pandemic strains. Therefore, universal flu vaccine approaches that induce broad immunity against conserved parts of influenza have top priority in research. Cross-reactive T cell responses, especially tissue-resident memory T cells in the respiratory tract, provide efficient heterologous immunity, and must therefore be a key component of universal flu vaccines. Here, we review recent findings about T cell-based flu immunity, with an emphasis on tissue-resident memory T cells in the respiratory tract of humans and different animal models. Furthermore, we provide an update on preclinical and clinical studies evaluating T cell-evoking flu vaccines, and discuss the implementation of T cell immunity in real-life vaccine policies.

scholarly journals A Missing Link: Engagements of Dendritic Cells in the Pathogenesis of SARS-CoV-2 Infections

2021 ◽  
Vol 22 (3) ◽  
pp. 1118
Author(s):  
Abdulaziz Alamri ◽  
Derek Fisk ◽  
Deepak Upreti ◽  
Sam K. P. Kung
Keyword(s):  
Dendritic Cells ◽  
Severe Acute Respiratory Syndrome ◽  
Immune Responses ◽  
Immune Cell ◽  
Inflammatory Responses ◽  
Viral Disease ◽  
Cell Recruitment ◽  
Cross Presentation ◽  
Cell Immunity ◽  
Immune Cell Recruitment

Dendritic cells (DC) connect the innate and adaptive arms of the immune system and carry out numerous roles that are significant in the context of viral disease. Their functions include the control of inflammatory responses, the promotion of tolerance, cross-presentation, immune cell recruitment and the production of antiviral cytokines. Based primarily on the available literature that characterizes the behaviour of many DC subsets during Severe acute respiratory syndrome (SARS) and coronavirus disease 2019 (COVID-19), we speculated possible mechanisms through which DC could contribute to COVID-19 immune responses, such as dissemination of Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) to lymph nodes, mounting dysfunctional inteferon responses and T cell immunity in patients. We highlighted gaps of knowledge in our understanding of DC in COVID-19 pathogenesis and discussed current pre-clinical development of therapies for COVID-19.

Interferon resistance of cutaneous T-cell lymphoma–derived clonal T-helper 2 cells allows selective viral replication

Blood ◽  
2001 ◽  
Vol 97 (2) ◽  
pp. 523-527 ◽  
Author(s):  
Reinhard Dummer ◽  
Udo Döbbeling ◽  
Ralf Geertsen ◽  
Jörg Willers ◽  
Günter Burg ◽  
...  
Keyword(s):  
T Cell ◽  
Viral Replication ◽  
Human Leukocyte ◽  
T Helper ◽  
Cd4 Cells ◽  
Efficient Treatment ◽  
T Helper 2 ◽  
Ifn Γ ◽  
The Impact

Abstract Cutaneous T-cell lymphomas (CTCL) comprise a heterogeneous group of lymphoproliferative disorders that are characterized by an accumulation of T-lymphocytes in the skin and occasionally in blood known as Sézary syndrome (SS). In most cases the dominant clone displays T-helper 2 cytokines. Because IFN-γ is a natural inhibitor of T-helper 2 cells and IFN-α is frequently used in CTCL, the impact of IFNs on SS-derived purified clonal T-helper 2 cells was studied using anti-Vβ antibodies. Moreover, IFNs are known to mediate virus resistance in normal cells. The isolated clonal CD4+ cells, but not the nonclonal CD4+ cells, appeared resistant to IFN-γ and IFN-α stimulation in terms of human leukocyte antigen up-regulation and MxA induction caused in part by alterations in Stat-1 molecule mRNA and IFNγR1 mRNA transcription. The IFN resistance of the patient-derived clonal cells was then targeted by vesicular stomatitis virus infection after IFN-α priming, resulting in selective viral replication in clonal cells. In contrast, nonclonal cells of the same patient showed IFN-dependent MxA expression, which is a major mediator protein of viral protection. The IFN resistance of the dominant T-helper 2 cells might be important for lymphomagenesis. Interferon signaling deficiencies can be targeted for purging patients' cells in vitro. Furthermore, this approach may allow specific molecular interventions, resulting in the efficient treatment of CTCL and other IFN-resistant neoplasms such as lung cancer.

scholarly journals Predominant T Helper 2 Immune Responses againstBartonella henselaein Naturally Infected Cats

2006 ◽  
Vol 50 (3) ◽  
pp. 171-178 ◽  
Author(s):  
Hidenori Kabeya ◽  
Makiko Sase ◽  
Masaya Yamashita ◽  
Soichi Maruyama
Keyword(s):  
Immune Responses ◽  
T Helper ◽  
T Helper 2

scholarly journals P04.06 mucosal immunization with a cDC1-targeted CTA1 adjuvant vaccine confers protection against melanoma metastasis

2020 ◽  
Vol 8 (Suppl 2) ◽  
pp. A39.1-A39
Author(s):  
M Arabpour ◽  
S Paul ◽  
R Kiffin ◽  
HG Wiktorin ◽  
K Hellstrand ◽  
...  
Keyword(s):  
T Cells ◽  
Dendritic Cells ◽  
T Cell ◽  
Immune Responses ◽  
Pulmonary Metastases ◽  
T Cell Immunity ◽  
Metastasis Formation ◽  
Mhc I ◽  
Mhc Ii ◽  
Cell Immunity

BackgroundSpecific targeting of anti-cancer vaccines to dendritic cells (DCs) has been shown to mount efficient immune responses against tumor cells. Classical CD103+dendritic cells (also called cDC1) have an inherent ability to cross-present antigens to CD8+ cytotoxic T cells. Here we have explored an anti-tumor vaccine that specifically targets cDC1 cells for protection against and elimination of metastatic melanoma. The vaccine contains the cholera toxin A1 subunit (CTA1) adjuvant and is targeted to cDC1 cells through an anti-CD103 single chain antibody (CD103 scFv).Material and MethodsC57BL/6 mice were injected with wild type or ovalbumin (OVA) expressing B16 melanoma cells either subcutaneously (s.c.) to establish solid tumors, or intravenously (i.v.) to allow the formation of pulmonary metastases. Before or after establishment of tumors, mice were intra-nasally inoculated with a vaccine composed of a CD103 scFv element fused to the adjuvant CTA1 and the MHC I H2kd-restricted OVA epitope SIINFEKL together with the MHC II H2kd-restricted OVA epitope p323 or just the p323 peptide alone (i.e. CTA1-SIINFEKL-p323-CD103 and CTA1-p323-CD103, respectively). Control mice were inoculated with PBS. The growth of solid tumors was carefully monitored and the development of pulmonary metastases was determined 2–3 weeks after tumor cell injection. In addition, antigen-specific T cell immunity following intranasal immunization was evaluated.ResultsTargeting MHC I and MHC II tumor cell epitopes to cDC1, via CD103 ScFv, in conjunction with the CTA1 adjuvant elicited strong tumor specific and protective CD8+ T cell responses as well as CD4+ T cell immunity. Immunization with the CTA1-SIINFEKL-p323-CD103 vaccine significantly reduced the growth of established solid B16F1-OVA melanomas (P<0.001) and potently prevented metastasis formation (P<0.01). Control immunizations with the CTA1-p323-CD103 vaccine tended to reduce metastasis, but tumor-specific CD8+ T cells were required for full therapeutic protection.ConclusionTargeting tumor specific CD8+ T cell epitopes to cDC1, in the context of a powerful adjuvant such as CTA1, leads to the development of efficient anti-tumor immune responses. Our results point towards the utility of cDC1-targeted vaccines in the treatment of established tumors or as a means to prevent metastasis formation.Disclosure InformationM. Arabpour: None. S. Paul: None. R. Kiffin: None. H.G. Wiktorin: None. K. Hellstrand: None. N. Lycke: None. A. Martner: None.

scholarly journals The immune battlefield: The impact of inflammatory cytokines on CD8+ T-cell immunity

2017 ◽  
Vol 13 (10) ◽  
pp. e1006618 ◽  
Author(s):  
Stephanie A. Condotta ◽  
Martin J. Richer
Keyword(s):  
T Cell ◽  
Inflammatory Cytokines ◽  
Cd8 T Cell ◽  
T Cell Immunity ◽  
Cell Immunity ◽  
The Impact

T-HELPER-1 AND T-HELPER-2 IMMUNE RESPONSES IN MICE INFECTED WITH THE INTESTINAL FLUKE NEODIPLOSTOMUM SEOULENSE: THEIR POSSIBLE ROLES IN WORM EXPULSION AND HOST FATALITY

2007 ◽  
Vol 93 (5) ◽  
pp. 1036-1045 ◽  
Author(s):  
Eun-Hee Shin ◽  
Sang-Hyup Lee ◽  
Jae-Lip Kim ◽  
Yun-Kyu Park ◽  
Jong-Yil Chai
Keyword(s):  
Immune Responses ◽  
T Helper ◽  
T Helper 1 ◽  
T Helper 2 ◽  
Worm Expulsion

scholarly journals 91. Differential Impact of Cytomegalovirus (CMV) Donor (D) Serostatus on Rates and Kinetics of CMV Viremia among CMV Seropositive Recipients (R+) of Ex vivo T-cell Depleted (TCD) and Unmodified (CONV) Hematopoietic Cell Transplants (HCT)

2019 ◽  
Vol 6 (Supplement_2) ◽  
pp. S7-S7
Author(s):  
Anat Stern ◽  
Yiqi Su ◽  
Jiaqi Fang ◽  
Miguel Perales ◽  
Molly Maloy ◽  
...  
Keyword(s):  
T Cell ◽  
Ex Vivo ◽  
Hematologic Malignancies ◽  
T Cell Immunity ◽  
Similar Frequency ◽  
Viral Loads ◽  
Cell Immunity ◽  
Cell Transplants ◽  
The Impact ◽  
Kinetics Of

Abstract Background In unmodified (CONV) HCT, CMV donor seropositivity (D+) conveys partial protection against CMV disease mediated by the transfer of donor CMV T-cell immunity through the allograft. Ex vivo T-cell depletion by CD34 selection affords a stringent depletion of donor T cells, thus transfer of donor T-cell immunity to CMV would be negligible. We evaluate the impact of CMV D serostatus on rates and kinetics of CMV viremia by Day (D)100 post-HCT in a contemporary cohort of CONV and TCD recipients from a single center. Methods A retrospective cohort study of R+ adult recipients of first peripheral blood or marrow HCT for hematologic malignancies (excluding multiple myeloma) from June 2010 to December 2017 at MSKCC. Routine CMV monitoring by a quantitative PCR assay occurred weekly from D14 through D100. Patients were treated preemptively. CMV viral burden was assessed as the time-averaged area under the viremia curve over 100 days from HCT (AAUC) calculated as the sum of the area of trapezoids of AUC viral loads divided by the number of weeks of follow-up viremia. The median AAUC for all patients with CMV reactivation (AAUC50) was used to classify patients as CMV controllers (AAUC ≤ AAUC50) or noncontrollers (AAUC >AAUC50). Results Of 509 R+, 290 (57%) patients received CONV and 219 (43%) TCD HCT; from 300 (59%) D+ and 209 (41%) D− donors. In CONV, CMV viremia occurred with similar frequency in D+ (65%) and D− (62%), P = 0.6. In contrast, in TCD, CMV viremia occurred more frequently in D+ compared with D− (83% vs. 71%, P = 0.03). Among CONV, D+ was associated with lower CMV burden (median AAUC) compared with D− (0.791 vs. 1.13, respectively, P = 0.0004). In contrast, in TCD, AAUC was similar between D− and D+ (1.19 vs. 1.35; P = 0.86). Among CONV with CMV viremia, D− were more likely to be noncontrollers compared with D+ (56% vs. 31%, respectively, P = 0.001). In contrast, among TCD with CMV viremia the proportion of noncontrollers was similar between D− and D+ (61% vs. 60%, respectively; P = 1). Conclusion Donor CMV serostatus has a differential effect on rates and kinetics of CMV viremia in R+ TCD and CONV HCT recipients. D+ is associated with less CMV viremia and less CMV burden in CONV but not in TCD. Our findings, if confirmed, have implications for donor selection algorithms. Disclosures All Authors: No reported Disclosures.

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