SARS-CoV-2 Omicron BA.4/BA.5 Mutations in Spike Leading to T Cell Escape in Recently Vaccinated Individuals.

SARS-CoV-2 Omicron (B.1.1.

Corrigendum: Children and Adults With Mild COVID-19: Dynamics of the Memory T Cell Response Up to 10 Months.

[This corrects the article DOI: 10.3389/fimmu.2022.

Children and Adults With Mild COVID-19: Dynamics of the Memory T Cell Response up to 10 Months.

Background: Severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) has led to considerable morbidity/mortality worldwide, but most infections, especially among children, have a mild course. However, it remains largely unknown whether infected children develop cellular immune memory.

Methods: To determine whether a memory T cell response is being developed, we performed a longitudinal assessment of the SARS-CoV-2-specific T cell response by IFN-γ ELISPOT and activation marker analyses of peripheral blood samples from unvaccinated children and adults with mild-to-moderate COVID-19.

Longitudinal Characterization of the Mumps-Specific HLA-A2 Restricted T-Cell Response after Mumps Virus Infection.

Waning of the mumps virus (MuV)-specific humoral response after vaccination has been suggested as a cause for recent mumps outbreaks in vaccinated young adults, although it cannot explain all cases. Moreover, CD8 T cells may play an important role in the response against MuV; however, little is known about the characteristics and dynamics of the MuV-specific CD8 T-cell response after MuV infection. Here, we had the opportunity to follow the CD8 T-cell response to three recently identified HLA-A2*02:01-restricted MuV-specific epitopes from 1.

Novel mumps virus epitopes reveal robust cytotoxic T cell responses after natural infection but not after vaccination.

Mumps is nowadays re-emerging despite vaccination. The contribution of T cell immunity to protection against mumps has not been clearly defined. Previously, we described a set of 41 peptides that were eluted from human leukocyte antigen (HLA) class I molecules of mumps virus (MuV)-infected cells.

Genetic Analysis Reveals Differences in CD8 T Cell Epitope Regions That May Impact Cross-Reactivity of Vaccine-Induced T Cells against Wild-Type Mumps Viruses.

Nowadays, mumps is re-emerging in highly vaccinated populations. Waning of vaccine-induced immunity plays a role, but antigenic differences between vaccine and mumps outbreak strains could also contribute to reduced vaccine effectiveness. CD8 T cells play a critical role in immunity to viruses.

Identification of Naturally Processed Mumps Virus Epitopes by Mass Spectrometry: Confirmation of Multiple CD8+ T-Cell Responses in Mumps Patients.

Background: The re-emergence of mumps among vaccinated young adults has become a global issue. Besides waning of antibody responses, suboptimal induction of T-cell responses may reduce protection. In a recent study, we observed a dominant polyfunctional CD8+ T-cell response after natural mumps virus (MuV) infection that was not present after vaccination.

The Human CD4 T Cell Response against Mumps Virus Targets a Broadly Recognized Nucleoprotein Epitope.

Mumps outbreaks among vaccinated young adults stress the need for a better understanding of mumps virus (MuV)-induced immunity. Antibody responses to MuV are well characterized, but studies on T cell responses are limited. We recently isolated a MuV-specific CD4 T cell clone by stimulating peripheral blood mononuclear cells (PBMCs) from a mumps case with the viral nucleoprotein (MuV-N).

Lenalidomide combined with low-dose cyclophosphamide and prednisone modulates Ikaros and Aiolos in lymphocytes, resulting in immunostimulatory effects in lenalidomide-refractory multiple myeloma patients.

We recently showed that the outcome of multiple myeloma (MM) patients treated in the REPEAT study (evaluation of lenalidomide combined with low-dose cyclophosphamide and prednisone (REP) in lenalidomide-refractory MM) was markedly better than what has been described with cyclophosphamide-prednisone alone. The outcome with REP was not associated with plasma cell Cereblon expression levels, suggesting that the effect of REP treatment may involve mechanisms independent of plasma cell Cereblon-mediated direct anti-tumor activity. We therefore hypothesized that immunomodulatory effects contribute to the anti-MM activity of REP treatment, rather than plasma cell Cereblon-mediated effects.

Development of an IFNγ ELISPOT for the analysis of the human T cell response against mumps virus.

In the last decade, mumps virus (MuV) causes outbreaks in highly vaccinated populations. Sub-optimal T cell immunity may play a role in the susceptibility to mumps in vaccinated individuals. T cell responses to mumps virus have been demonstrated, yet the quality of the MuV-specific T cell response has not been analyzed using single cell immunological techniques.

Altered peptide ligands revisited: vaccine design through chemically modified HLA-A2-restricted T cell epitopes.

Virus or tumor Ag-derived peptides that are displayed by MHC class I molecules are attractive starting points for vaccine development because they induce strong protective and therapeutic cytotoxic T cell responses. In thus study, we show that the MHC binding and consequent T cell reactivity against several HLA-A*02 restricted epitopes can be further improved through the incorporation of nonproteogenic amino acids at primary and secondary anchor positions. We screened more than 90 nonproteogenic, synthetic amino acids through a range of epitopes and tested more than 3000 chemically enhanced altered peptide ligands (CPLs) for binding affinity to HLA-A*0201.

Interleukin-17 production and T helper 17 cells in peripheral blood mononuclear cells in response to ocular lysate in patients with birdshot chorioretinopathy.

Purpose: To determine the cytokine response to ocular lysates of peripheral blood mononuclear cells (PBMCs) from patients with birdshot chorioretinopathy (BSCR).

Methods: In the PBMCs of 19 patients with BSCR, T cell cytokine production in response to human retina and choroid lysates was analyzed with flow cytometry and compared to the responses against skin lysates. Five patients had active disease and had not yet been treated (naïve to systemic therapy); 14 patients had either immunomodulatory therapy (IMT) or inactive disease (referred as inactive/IMT).

Lenalidomide maintenance after nonmyeloablative allogeneic stem cell transplantation in multiple myeloma is not feasible: results of the HOVON 76 Trial.

To improve the outcome of allogeneic stem cell transplantation (allo-SCT) in multiple myeloma as part of first-line treatment, we prospectively investigated the feasibility and efficacy of lenalidomide maintenance. Patients started maintenance 1 to 6 months after nonmyeloablative allo-SCT. Lenalidomide was dosed 10 mg on days 1 to 21 of a 28-day schedule for a total of 24 cycles.

A bioluminescence imaging based in vivo model for preclinical testing of novel cellular immunotherapy strategies to improve the graft-versus-myeloma effect.

Background: The development and preclinical testing of novel immunotherapy strategies for multiple myeloma can benefit substantially from a humanized animal model that enables quantitative real-time monitoring of tumor progression. Here we have explored the feasibility of establishing such a model in immunodeficient RAG2(-/-)gammac(-/-) mice, by utilizing non-invasive bioluminescent imaging for real-time monitoring of multiple myeloma cell growth.

Design And Methods: Seven multiple myeloma cell lines, marked with a green fluorescent protein firefly luciferase fusion gene, were intravenously injected into RAG2(-/-)gammac(-/-) mice.

Forced overexpression of either of the two common human Foxp3 isoforms can induce regulatory T cells from CD4(+)CD25(-) cells.

The forkhead/winged helix transcription factor (Foxp3) is expressed as two different isoforms in humans: the full-length isoform (Foxp3FL) and an alternative-splicing product lacking the exon 2 (Foxp3DeltaE2). We here studied the cellular distribution of Foxp3 isoforms by quantitative PCR and evaluated the functional outcome of retroviral transduction of Foxp3FL and Foxp3DeltaE2 genes into CD4(+)CD25(-) cells. In PBMC, both isoforms were preferentially expressed in CD4(+)CD25(hi) cells.

Human regulatory T cells control xenogeneic graft-versus-host disease induced by autologous T cells in RAG2-/-gammac-/- immunodeficient mice.

Purpose: Effective prevention of graft-versus-host disease (GvHD) is a major challenge to improve the safety of allogeneic stem cell transplantation for leukemia treatment. In murine transplantation models, administration of naturally occurring CD4+CD25+ regulatory T cells (Treg) can prevent GvHD. Toward understanding the role of human Treg in stem cell transplantation, we studied their capacity to modulate T-cell-dependent xenogeneic (x)-GvHD in a new model where x-GvHD is induced in RAG2-/-gammac-/- mice by i.