Aberrant adaptive immune response underlies genetic susceptibility to tuberculosis.

() remains a major threat worldwide, although only a fraction of infected individuals develops tuberculosis (TB). TB susceptibility is shaped by multiple genetic factors, and we performed comparative immunological analysis of two mouse strains to uncover relevant mechanisms underlying susceptibility and resistance. C57BL/6 mice are relatively TB-resistant, whereas I/St mice are prone to develop severe TB, partly due to the MHC-II allelic variant that shapes suboptimal CD4 T cell receptor repertoire.

Local Enrichment with Convergence of Enriched T-Cell Clones Are Hallmarks of Effective Peptide Vaccination against B16 Melanoma.

Background: Some peptide anticancer vaccines elicit a strong T-cell memory response but fail to suppress tumor growth. To gain insight into tumor resistance, we compared two peptide vaccines, p20 and p30, against B16 melanoma, with both exhibiting good in vitro T-cell responses but different tumor suppression abilities.

Methods: We compared activation markers and repertoires of T-lymphocytes from tumor-draining (dLN) and non-draining (ndLN) lymph nodes for the two peptide vaccines.

Clonal structure and the specificity of vaccine-induced T cell response to SARS-CoV-2 Spike protein.

Adenovirus vaccines, particularly the COVID-19 Ad5-nCoV adenovirus vaccine, have emerged as promising tools in the fight against infectious diseases. In this study, we investigated the structure of the T cell response to the Spike protein of the SARS-CoV-2 virus used in the COVID-19 Ad5-nCoV adenoviral vaccine in a phase 3 clinical trial (NCT04540419). In 69 participants, we collected peripheral blood samples at four time points after vaccination or placebo injection.

Targeted depletion of TRBV9 T cells as immunotherapy in a patient with ankylosing spondylitis.

Autoimmunity is intrinsically driven by memory T and B cell clones inappropriately targeted at self-antigens. Selective depletion or suppression of self-reactive T cells remains a holy grail of autoimmune therapy, but disease-associated T cell receptors (TCRs) and cognate antigenic epitopes remained elusive. A TRBV9-containing CD8 TCR motif was recently associated with the pathogenesis of ankylosing spondylitis, psoriatic arthritis and acute anterior uveitis, and cognate HLA-B*27-presented epitopes were identified.

Naïve Regulatory T Cell Subset Is Altered in X-Linked Agammaglobulinemia.

The interplay between T- and B-cell compartments during naïve, effector and memory T cell maturation is critical for a balanced immune response. Primary B-cell immunodeficiency arising from X-linked agammaglobulinemia (XLA) offers a model to explore B cell impact on T cell subsets, starting from the thymic selection. Here we investigated characteristics of naïve and effector T cell subsets in XLA patients, revealing prominent alterations in the corresponding T-cell receptor (TCR) repertoires.

Functionally specialized human CD4 T-cell subsets express physicochemically distinct TCRs.

The organizational integrity of the adaptive immune system is determined by functionally discrete subsets of CD4 T cells, but it has remained unclear to what extent lineage choice is influenced by clonotypically expressed T-cell receptors (TCRs). To address this issue, we used a high-throughput approach to profile the αβ TCR repertoires of human naive and effector/memory CD4 T-cell subsets, irrespective of antigen specificity. Highly conserved physicochemical and recombinatorial features were encoded on a subset-specific basis in the effector/memory compartment.

Measuring Intratumoral Heterogeneity of Immune Repertoires.

There is considerable clinical and fundamental value in measuring the clonal heterogeneity of T and B cell expansions in tumors and tumor-associated lymphoid structures-along with the associated heterogeneity of the tumor neoantigen landscape-but such analyses remain challenging to perform. Here, we propose a straightforward approach to analyze the heterogeneity of immune repertoires between different tissue sections in a quantitative and controlled way, based on a beta-binomial noise model trained on control replicates obtained at the level of single-cell suspensions. This approach allows to identify local clonal expansions with high accuracy.

RNA-Seq-Based TCR Profiling Reveals Persistently Increased Intratumoral Clonality in Responders to Anti-PD-1 Therapy.

Substantial effort is being invested in the search for peripheral or intratumoral T cell receptor (TCR) repertoire features that could predict the response to immunotherapy. Here we demonstrate the utility of MiXCR software for TCR and immunoglobulin repertoire extraction from RNA-Seq data obtained from sorted tumor-infiltrating T and B cells. We use this approach to extract TCR repertoires from RNA-Seq data obtained from sorted tumor-infiltrating CD4 and CD8 T cells in an HKP1 (Krasp53) syngeneic mouse model of lung cancer after anti-PD-1 treatment.

Application of nonsense-mediated primer exclusion (NOPE) for preparation of unique molecular barcoded libraries.

Background: Recently we proposed efficient method to exclude undesirable primers at any stage of amplification reaction, here termed NOPE (NOnsense-mediated Primer Exclusion). According to this method, added oligonucleotide overlapping with the 3'-end of unwanted amplification primer (NOPE oligo) simultaneously provides a template for its elongation. This elongation disrupts specificity of unwanted primer, preventing its further participation in PCR.

A high-throughput assay for quantitative measurement of PCR errors.

The accuracy with which DNA polymerase can replicate a template DNA sequence is an extremely important property that can vary by an order of magnitude from one enzyme to another. The rate of nucleotide misincorporation is shaped by multiple factors, including PCR conditions and proofreading capabilities, and proper assessment of polymerase error rate is essential for a wide range of sensitive PCR-based assays. In this paper, we describe a method for studying polymerase errors with exceptional resolution, which combines unique molecular identifier tagging and high-throughput sequencing.

MAGERI: Computational pipeline for molecular-barcoded targeted resequencing.

Unique molecular identifiers (UMIs) show outstanding performance in targeted high-throughput resequencing, being the most promising approach for the accurate identification of rare variants in complex DNA samples. This approach has application in multiple areas, including cancer diagnostics, thus demanding dedicated software and algorithms. Here we introduce MAGERI, a computational pipeline that efficiently handles all caveats of UMI-based analysis to obtain high-fidelity mutation profiles and call ultra-rare variants.

A digestive prolyl carboxypeptidase in Tenebrio molitor larvae.

Prolyl carboxypeptidase (PRCP) is a lysosomal proline specific serine peptidase that also plays a vital role in the regulation of physiological processes in mammals. In this report, we isolate and characterize the first PRCP in an insect. PRCP was purified from the anterior midgut of larvae of a stored product pest, Tenebrio molitor, using a three-step chromatography strategy, and it was determined that the purified enzyme was a dimer.

Normalization of full-length-enriched cDNA.

A well-recognized obstacle to efficient high-throughput analysis of cDNA libraries is the differential abundance of various transcripts in any particular cell type. Decreasing the prevalence of clones representing abundant transcripts before sequencing, using cDNA normalization, may significantly increase the efficacy of random sequencing and is essential for rare gene discovery. Duplex-specific nuclease (DSN) normalization allows the generation of normalized full-length-enriched cDNA libraries to permit a high gene discovery rate.

A new set of markers for human identification based on 32 polymorphic Alu insertions.

A number of genetic systems for human genetic identification based on short tandem repeats or single nucleotide polymorphisms are widely used for crime detection, kinship studies and in analysis of victims of mass disasters. Here, we have developed a new set of 32 molecular genetic markers for human genetic identification based on polymorphic retroelement insertions. Allele frequencies were determined in a group of 90 unrelated individuals from four genetically distant populations of the Russian Federation.

DSN depletion is a simple method to remove selected transcripts from cDNA populations.

A novel DSN-depletion method allows elimination of selected sequences from full-length-enriched cDNA libraries. Depleted cDNA can be applied for subsequent EST sequencing, expression cloning, and functional screening approaches. The method employs specific features of the kamchatka crab duplex-specific nuclease (DSN).

Decoding the fine-scale structure of a breast cancer genome and transcriptome.

A comprehensive understanding of cancer is predicated upon knowledge of the structure of malignant genomes underlying its many variant forms and the molecular mechanisms giving rise to them. It is well established that solid tumor genomes accumulate a large number of genome rearrangements during tumorigenesis. End Sequence Profiling (ESP) maps and clones genome breakpoints associated with all types of genome rearrangements elucidating the structural organization of tumor genomes.