Efficient and sustained locus editing in hematopoietic stem cells as a therapeutic approach for IPEX syndrome.

Immune dysregulation, polyendocrinopathy, enteropathy, X-linked (IPEX) syndrome is a monogenic disorder caused by mutations in the gene, required for generation of regulatory T (T) cells. Loss of T cells leads to immune dysregulation characterized by multi-organ autoimmunity and early mortality. Hematopoietic stem cell (HSC) transplantation can be curative, but success is limited by autoimmune complications, donor availability and/or graft-vs.

Multiple early factors anticipate post-acute COVID-19 sequelae.

Post-acute sequelae of COVID-19 (PASC) represent an emerging global crisis. However, quantifiable risk factors for PASC and their biological associations are poorly resolved. We executed a deep multi-omic, longitudinal investigation of 309 COVID-19 patients from initial diagnosis to convalescence (2-3 months later), integrated with clinical data and patient-reported symptoms.

Ontogeny of different subsets of yellow fever virus-specific circulatory CXCR5 CD4 T cells after yellow fever vaccination.

Monitoring the frequency of circulatory CXCR5 (cCXCR5) CD4 T cells in periphery blood provides a potential biomarker to draw inferences about T follicular helper (T) activity within germinal center. However, cCXCR5 T cells are highly heterogeneous in their expression of ICOS, PD1 and CD38 and the relationship between different cCXCR5 subsets as delineated by these markers remains unclear. We applied class II tetramer reagents and mass cytometry to investigate the ontogeny of different subsets of cCXCR5 T cell following yellow fever immunization.

Magnitude and Dynamics of the T-Cell Response to SARS-CoV-2 Infection at Both Individual and Population Levels.

T cells are involved in the early identification and clearance of viral infections and also support the development of antibodies by B cells. This central role for T cells makes them a desirable target for assessing the immune response to SARS-CoV-2 infection. Here, we combined two high-throughput immune profiling methods to create a quantitative picture of the T-cell response to SARS-CoV-2.

Ratiometric Barcoding for Mass Cytometry.

Barcoding is of importance for high-throughput cellular and molecular analysis. A ratiometric barcoding strategy using lanthanide-coordinated polymer dots (Ln-Pdots) was developed for mass cytometric analysis. By using 3 metal isotopes and 4 ratio intensity levels, 16 barcodes were generated to code, and later decode, cell samples in mass cytometry.

Lanthanide-Coordinated Semiconducting Polymer Dots Used for Flow Cytometry and Mass Cytometry.

Simultaneous monitoring of biomarkers as well as single-cell analyses based on flow cytometry and mass cytometry are important for investigations of disease mechanisms, drug discovery, and signaling-network studies. Flow cytometry and mass cytometry are complementary to each other; however, probes that can satisfy all the requirements for these two advanced technologies are limited. In this study, we report a probe of lanthanide-coordinated semiconducting polymer dots (Pdots), which possess fluorescence and mass signals.

Immunization with single-cycle SIV significantly reduces viral loads after an intravenous challenge with SIV(mac)239.

Strains of simian immunodeficiency virus (SIV) that are limited to a single cycle of infection were evaluated for the ability to elicit protective immunity against wild-type SIV(mac)239 infection of rhesus macaques by two different vaccine regimens. Six animals were inoculated at 8-week intervals with 6 identical doses consisting of a mixture of three different envelope variants of single-cycle SIV (scSIV). Six additional animals were primed with a mixture of cytoplasmic domain-truncated envelope variants of scSIV and boosted with two doses of vesicular stomatitis virus glycoprotein (VSV G) trans-complemented scSIV.

Selective downregulation of rhesus macaque and sooty mangabey major histocompatibility complex class I molecules by Nef alleles of simian immunodeficiency virus and human immunodeficiency virus type 2.

Human immunodeficiency virus type 1 (HIV-1) Nef downregulates HLA-A and -B molecules, but not HLA-C or -E molecules, based on amino acid differences in their cytoplasmic domains to simultaneously evade cytotoxic T lymphocyte (CTL) and natural killer cell surveillance. Rhesus macaques and sooty mangabeys express orthologues of HLA-A, -B, and -E, but not HLA-C, and many of these molecules have unique amino acid differences in their cytoplasmic tails. We found that these differences also resulted in differential downregulation by primary simian immunodeficiency virus (SIV) SIV(smm/mac) and HIV-2 Nef alleles.

Selective downmodulation of HLA-A and -B by Nef alleles from different groups of primate lentiviruses.

It has been demonstrated that the HIV-1 NL4-3 and IIIB Nef alleles downregulate HLA-A and -B but not -C or -E from the cell surface. It remained elusive, however, whether selective modulation of specific HLA molecules is conserved between different groups of human and simian immunodeficiency viruses, respectively. To address this, we analyzed a large panel of primate lentiviral Nef proteins and we found that this property is conserved among nef alleles from the M, N and O groups of HIV-1, as well as those from SIVcpz, the precursor of HIV-1, and a variety of other highly divergent primate lentiviruses.

Comparison of plasma viremia and antibody responses in macaques inoculated with envelope variants of single-cycle simian immunodeficiency virus differing in infectivity and cellular tropism.

Molecular differences in the envelope glycoproteins of human immunodeficiency virus type 1 and simian immunodeficiency virus (SIV) determine virus infectivity and cellular tropism. To examine how these properties contribute to productive infection in vivo, rhesus macaques were inoculated with strains of single-cycle SIV (scSIV) engineered to express three different envelope glycoproteins with full-length (TM(open)) or truncated (TM(stop)) cytoplasmic tails. The 239 envelope uses CCR5 for infection of memory CD4(+) T cells, the 316 envelope also uses CCR5 but has enhanced infectivity for primary macrophages, and the 155T3 envelope uses CXCR4 for infection of both naive and memory CD4(+) T cells.