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1.
J Hum Genet ; 68(10): 705-712, 2023 Oct.
Article in English | MEDLINE | ID: mdl-37316650

ABSTRACT

Due to the geographical proximity of the northern coast of the Sea of Okhotsk and Kamchatka Peninsula to the Beringia, the indigenous populations of these territories are of great interest for elucidating the human settlement history of northern Asia and America. Meanwhile, there is a clear shortage of genetic studies of the indigenous populations of the northern coast of the Sea of Okhotsk. Here, in order to examine their fine-scale matrilineal genetic structure, ancestry and relationships with neighboring populations, we analyzed 203 complete mitogenomes (174 of which are new) from population samples of the Koryaks and Evens of the northern coast of the Sea of Okhotsk and the Chukchi of the extreme northeast Asia. The patterns observed underscore the reduced level of genetic diversity found in the Koryak, Even, and Chukchi populations, which, along with the high degree of interpopulation differentiation, may be the result of genetic drift. Our phylogeographic analysis reveals common Paleo-Asiatic ancestry for 51.1% of the Koryaks and 17.8% of the Evens. About third of the mitogenomes found in the Koryaks and Evens might be considered as ethno-specific, as these are virtually absent elsewhere in North, Central and East Asia. Coalescence ages of most of these lineages coincide well with the emergence and development of the Tokarev and Old Koryak archaeological cultures associated with the formation of the Koryaks, as well as with the period of separation and split of the North Tungusic groups migrated northwards from the Lake Baikal or the Amur River area.


Subject(s)
DNA, Mitochondrial , Genomics , North Asian People , Humans , DNA, Mitochondrial/genetics , Genetic Variation/genetics , North Asian People/ethnology , North Asian People/genetics , Phylogeography , Indigenous Peoples/genetics
2.
Mol Genet Genomics ; 297(1): 47-62, 2022 Jan.
Article in English | MEDLINE | ID: mdl-34757478

ABSTRACT

Here, we present a comprehensive data set of 489 complete mitogenomes (211 of which are new) from four Mongolic-speaking populations (Mongols, Barghuts, Khamnigans, and Buryats) to investigate their matrilineal genetic structure, ancestry and relationship with other ethnic groups. We show that along with very high levels of genetic diversity and lack of genetic differentiation, Mongolic-speaking populations exhibit strong genetic resemblance to East Asian populations of Chinese, Japanese, and Uyghurs. Phylogeographic analysis of complete mitogenomes reveals the presence of different components in the gene pools of modern Mongolic-speaking populations-the main East Eurasian component is represented by mtDNA lineages of East Asian, Siberian and autochthonous (the Baikal region/Mongolian) ancestry, whereas the less pronounced West Eurasian component can be ascribed to Europe and West Asia/Caucasus. We also observed that up to one third of the mtDNA subhaplogroups identified in Mongolic-speaking populations can be considered as Mongolic-specific with the coalescence age of most of them not exceeding 1.7 kya. This coincides well with the population size growth which started around 1.1 kya and is detectable only in the Bayesian Skyline Plot constructed based on Mongolic-specific mitogenomes. Our data suggest that the genetic structure established during the Mongol empire is still retained in present-day Mongolic-speaking populations.


Subject(s)
DNA, Mitochondrial/genetics , Ethnicity/genetics , Asian People/ethnology , Asian People/genetics , Bayes Theorem , DNA, Mitochondrial/analysis , Gene Pool , Genetic Variation , Genetics, Population , Genomics/methods , Haplotypes , Humans , Language , Mongolia/epidemiology , Mongolia/ethnology , Phylogeny , Phylogeography
3.
Cytotherapy ; 23(9): 820-832, 2021 09.
Article in English | MEDLINE | ID: mdl-34217618

ABSTRACT

BACKGROUND AIMS: T cells engineered with synthetic receptors have delivered powerful therapeutic results for patients with relapsed/refractory hematologic malignancies. The authors have recently described the T-cell antigen coupler (TAC) receptor, which co-opts the endogenous T-cell receptor (TCR) and activates engineered T cells in an HLA-independent manner. Here the authors describe the evolution of a next-generation TAC receptor with a focus on developing a TAC-engineered T cell for multiple myeloma. METHODS: To optimize the TAC scaffold, the authors employed a bona fide antigen-binding domain derived from the B-cell maturation antigen-specific monoclonal antibody C11D5.3, which has been used successfully in the clinic. The authors first tested humanized versions of the UCHT1 domain, which is used by the TAC to co-opt the TCR. The authors further discovered that the signal peptide affected surface expression of the TAC receptor. Higher density of the TAC receptor enhanced target binding in vitro, which translated into higher levels of Lck at the immunological synapse and stronger proliferation when only receptor-ligand interactions were present. RESULTS: The authors observed that the humanized UCHT1 improved surface expression and in vivo efficacy. Using TAC T cells derived from both healthy donors and multiple myeloma patients, the authors determined that despite the influence of receptor density on early activation events and effector function, receptor density did not impact late effector functions in vitro, nor did the receptor density affect in vivo efficacy. CONCLUSIONS: The modifications to the TAC scaffold described herein represent an important step in the evolution of this technology, which tolerates a range of expression levels without impacting therapeutic efficacy.


Subject(s)
B-Cell Maturation Antigen , Multiple Myeloma , Humans , Immunotherapy, Adoptive , Multiple Myeloma/therapy , Neoplasm Recurrence, Local , Receptors, Antigen, T-Cell/genetics , T-Lymphocytes
4.
Mol Genet Genomics ; 294(6): 1547-1559, 2019 Dec.
Article in English | MEDLINE | ID: mdl-31372716

ABSTRACT

Distinctive peculiarities of Armenians such as their millennia-long genetic isolation and strong national identity attract a keen interest while studying the demographic history of the West Asia. Here, to examine their fine-scale matrilineal genetic structure, ancestry and relationships with neighboring populations, we analyzed 536 complete mitogenomes (141 of which are novel) from 8 geographically different Armenian populations, covering the whole stretch of historical Armenia. The observed patterns highlight a remarkable degree of matrilineal genetic heterogeneity and weak population structuring of Armenians. Moreover, our phylogeographic analysis reveals common ancestries for some mtDNA lineages shared by West Asians, Transcaucasians, Europeans, Central Asians and Armenians. About third of the mtDNA subhaplogroups found in Armenian gene pool might be considered as Armenian-specific, as these are virtually absent elsewhere in Europe, West Asia and Transcaucasia. Coalescence ages of most of these lineages do not exceed 3.1 kya and coincide well with the population size growth started around 1.8-2.8 kya detectable only in the Bayesian Skyline Plots based on the Armenian-specific mtDNA haplotypes.


Subject(s)
Genome, Mitochondrial , Armenia , Asia, Central , Asia, Western , DNA, Mitochondrial/chemistry , Europe , Genetic Variation , Haplotypes , Humans , Phylogeny , Phylogeography
5.
Mol Genet Genomics ; 293(5): 1255-1263, 2018 Oct.
Article in English | MEDLINE | ID: mdl-29948329

ABSTRACT

Complete mitochondrial genomics is an effective tool for studying the demographic history of human populations, but there is still a deficit of mitogenomic data in European populations. In this paper, we present results of study of variability of 80 complete mitochondrial genomes in two Hungarian populations from eastern part of Hungary (Szeged and Debrecen areas). The genetic diversity of Hungarian mitogenomes is remarkably high, reaching 99.9% in a combined sample. According to the analysis of molecular variance (AMOVA), European populations showed a low, but statistically significant level of between-population differentiation (Fst = 0.61%, p = 0), and two Hungarian populations demonstrate lack of between-population differences. Phylogeographic analysis allowed us to identify 71 different mtDNA sub-clades in Hungarians, sixteen of which are novel. Analysis of ancestry-informative mtDNA sub-clades revealed a complex genetic structure associated with the genetic impact of populations from different parts of Eurasia, though the contribution from European populations is the most pronounced. At least 8% of ancestry-informative haplotypes found in Hungarians demonstrate similarity with East and West Slavic populations (sub-clades H1c23a, H2a1c1, J2b1a6, T2b25a1, U4a2e, K1c1j, and I1a1c), while the influence of Siberian populations is not so noticeable (sub-clades A12a, C4a1a, and probably U4b1a4).


Subject(s)
DNA, Mitochondrial/genetics , Ethnicity/genetics , Genetic Variation , Genetics, Population , Genome, Mitochondrial , Haplotypes , Humans , Hungary , Phylogeography
6.
J Hum Genet ; 63(1): 71-81, 2018 Jan.
Article in English | MEDLINE | ID: mdl-29215085

ABSTRACT

In this paper we present a results of first comprehensive study of the complete mitogenomes in the Buryats with regard to their belonging to the main regional (eastern and western Buryats); tribal (Khori, Ekhirid, Bulagad, and Khongodor), and ethno-territorial (Aginsk, Alar, Balagansk, Barguzin, Ida, Khorinsk, Kuda, Selenga, Verkholensk, Olkhon, Tunka, and Shenehen Buryats) groups. The analysis of molecular variation performed using regional, tribal, and ethno-territorial divisions of the Buryats showed lack of genetic differentiation at all levels. Nonetheless, the complete mitogenome analysis revealed a very high level of genetic diversity in the Buryats which is the highest among Siberian populations and comparable to that in populations of eastern and western Asia. The AMOVA and MDS analyses results imply to a strong genetic similarity between the Buryats and eastern Asian populations of Chinese and Japanese, suggesting their origin on the basis of common maternal ancestry components. Several new Buryat-specific branches of haplogroup G (G2a2a, G2a1i, G2a5a) display signals of dispersals dating to 2.6-6.6 kya with a possible origin in eastern Asia, thus testifying Bronze Age and Neolithic arrival of ancestral eastern Asian component to the South Siberia region.


Subject(s)
Asian People/ethnology , Asian People/genetics , DNA, Mitochondrial/genetics , Genome, Mitochondrial , Phylogeny , Female , Humans , Male , Siberia/ethnology
7.
J Hum Genet ; 61(6): 491-6, 2016 Jun.
Article in English | MEDLINE | ID: mdl-26911356

ABSTRACT

Y chromosome microsatellite (Y-STR) diversity has been studied in different Mongolic-speaking populations from South Siberia, Mongolia, North-East China and East Europe. The results obtained indicate that the Mongolic-speaking populations clustered into two groups, with one group including populations from eastern part of South Siberia and Central Asia (the Buryats, Barghuts and Khamnigans) and the other group including populations from western part of Central Asia and East Europe (the Mongols and Kalmyks). High frequency of haplogroup C3-M407 (>50%) is present in the Buryats, Barghuts and Khamnigans, whereas in the Mongols and Kalmyks its frequency is much lower. In addition, two allelic combinations in DYS385a,b loci of C3-M407 haplotypes have been observed: the combination 11,18 (as well as 11,17 and 11,19) is frequent in different Mongolic-speaking populations, but the 11,11 branch is present mainly in the Kalmyks and Mongols. Results of locus-specific sequencing suggest that the action of gene conversion is a more likely explanation for origin of homoallelic 11,11 combination. Moreover, analysis of median networks of Y-STR haplotypes demonstrates that at least two gene conversion events can be revealed-one of them has probably occurred among the Mongols, and the other event occurred in the Barghuts. These two events give an average gene conversion rate range of 0.24-7.1 × 10(-3) per generation.


Subject(s)
Asian People/genetics , Chromosomes, Human, Y , Gene Conversion , Genetic Variation , Genetics, Population , Haplotypes , Microsatellite Repeats , Alleles , China , Cluster Analysis , Ethnicity/genetics , Evolution, Molecular , Gene Frequency , Genetic Loci , Humans , Male , Mutation , Russia
8.
Mol Ther ; 23(10): 1600-10, 2015 Oct.
Article in English | MEDLINE | ID: mdl-26122933

ABSTRACT

Ligands for the NKG2D receptor are overexpressed on tumors, making them interesting immunotherapy targets. To assess the tumoricidal properties of T cells directed to attack NKG2D ligands, we engineered murine T cells with two distinct NKG2D-based chimeric antigen receptors (CARs): (i) a fusion between the NKG2D receptor and the CD3ζ chain and (ii) a conventional second-generation CAR, where the extracellular domain of NKG2D was fused to CD28 and CD3ζ. To enhance the CAR surface expression, we also engineered T cells to coexpress DAP10. In vitro functionality and surface expression levels of all three CARs was greater in BALB/c T cells than C57BL/6 T cells, indicating strain-specific differences. Upon adoptive transfer of NKG2D-CAR-T cells into syngeneic animals, we observed significant clinical toxicity resulting in morbidity and mortality. The severity of these toxicities varied between the CAR configurations and paralleled their in vitro NKG2D surface expression. BALB/c mice were more sensitive to these toxicities than C57BL/6 mice, consistent with the higher in vitro functionality of BALB/c T cells. Treatment with cyclophosphamide prior to adoptive transfer exacerbated the toxicity. We conclude that while NKG2D ligands may be useful targets for immunotherapy, the pursuit of NKG2D-based CAR-T cell therapies should be undertaken with caution.


Subject(s)
Cytotoxicity, Immunologic , Recombinant Fusion Proteins , Adoptive Transfer , Animals , Cell Line, Tumor , Cell Membrane/metabolism , Cyclophosphamide/pharmacology , Cytokines/metabolism , Disease Models, Animal , Female , Gene Expression , Genetic Vectors/genetics , Immunotherapy, Adoptive , Ligands , Mice , NK Cell Lectin-Like Receptor Subfamily K/metabolism , Neoplasms/genetics , Neoplasms/immunology , Neoplasms/pathology , Neoplasms/therapy , Pneumonia/immunology , Pneumonia/metabolism , Pneumonia/pathology , Receptors, Antigen, T-Cell/genetics , Receptors, Antigen, T-Cell/metabolism , Receptors, Immunologic/genetics , Receptors, Immunologic/metabolism , Retroviridae/genetics , T-Lymphocytes/immunology , T-Lymphocytes/metabolism , Transplantation Conditioning
9.
BMC Evol Biol ; 14: 217, 2014 Oct 10.
Article in English | MEDLINE | ID: mdl-25301575

ABSTRACT

BACKGROUND: Although the genetic heritage of aboriginal Siberians is mostly of eastern Asian ancestry, a substantial western Eurasian component is observed in the majority of northern Asian populations. Traces of at least two migrations into southern Siberia, one from eastern Europe and the other from western Asia/the Caucasus have been detected previously in mitochondrial gene pools of modern Siberians. RESULTS: We report here 166 new complete mitochondrial DNA (mtDNA) sequences that allow us to expand and re-analyze the available data sets of western Eurasian lineages found in northern Asian populations, define the phylogenetic status of Siberian-specific subclades and search for links between mtDNA haplotypes/subclades and events of human migrations. From a survey of 158 western Eurasian mtDNA genomes found in Siberia we estimate that nearly 40% of them most likely have western Asian and another 29% European ancestry. It is striking that 65 of northern Asian mitogenomes, i.e. ~41%, fall into 19 branches and subclades which can be considered as Siberian-specific being found so far only in Siberian populations. From the coalescence analysis it is evident that the sequence divergence of Siberian-specific subclades was relatively small, corresponding to only 0.6-9.5 kya (using the complete mtDNA rate) and 1-6 kya (coding region rate). CONCLUSIONS: The phylogeographic analysis implies that the western Eurasian founders, giving rise to Siberian specific subclades, may trace their ancestry only to the early and mid-Holocene, though some of genetic lineages may trace their ancestry back to the end of Last Glacial Maximum (LGM). We have not found the modern northern Asians to have western Eurasian genetic components of sufficient antiquity to indicate traces of pre-LGM expansions.


Subject(s)
DNA, Mitochondrial/genetics , Gene Pool , Genetics, Population , Asian People/genetics , Female , Genetics, Medical , Humans , Molecular Sequence Data , Phylogeny , Phylogeography , Siberia , White People/genetics
10.
Mol Ther Oncol ; 32(3): 200842, 2024 Sep 19.
Article in English | MEDLINE | ID: mdl-39045028

ABSTRACT

Proximity-induction of cell-cell interactions via small molecules represents an emerging field in basic and translational sciences. Covalent anchoring of these small molecules represents a useful chemical strategy to enforce proximity; however, it remains largely unexplored for driving cell-cell interactions. In immunotherapeutic applications, bifunctional small molecules are attractive tools for inducing proximity between immune effector cells like T cells and tumor cells to induce tumoricidal function. We describe a two-component system composed of electrophilic bifunctional small molecules and paired synthetic antigen receptors (SARs) that elicit T cell activation. The molecules, termed covalent immune recruiters (CIRs), were designed to affinity label and covalently engage SARs. We evaluated the utility of CIRs to direct anti-tumor function of human T cells engineered with three biologically distinct classes of SAR. Irrespective of the electrophilic chemistry, tumor-targeting moiety, or SAR design, CIRs outperformed equivalent non-covalent bifunctional adapters, establishing a key role for covalency in maximizing functionality. We determined that covalent linkage enforced early T cell activation events in a manner that was dependent upon each SARs biology and signaling threshold. These results provide a platform to optimize universal SAR-T cell functionality and more broadly reveal new insights into how covalent adapters modulate cell-cell proximity-induction.

11.
J Hum Genet ; 58(12): 804-11, 2013 Dec.
Article in English | MEDLINE | ID: mdl-24132124

ABSTRACT

The Mongolic-speaking Kalmyks currently inhabiting the steppes of the Volga region have Central Asian ancestry and are organized into the tribal groups. The genetic relationships among these tribes and their origin have remained obscure. We analyzed 17 short tandem repeat and 44 binary polymorphisms of Y-chromosome in 426 individuals mainly from three major tribes of the Kalmyks (the Torguuds, Dörwöds and Khoshuuds). Among these tribes, the Dörwöds and Torguuds, as well as the Kalmyks collectively as an ethnic group, showed relatively close genetic affinities to each other and to the Mongols and Altaian Kazakhs, whereas the Khoshuuds were clearly separated from all of them, gathering with the Manchu, Tibetans or Evenks (depending on the algorithm used to calculate genetic distances). The genetic results also indicate that paternal gene flow from East Europeans to the Kalmyks is very little, despite their cohabitation in the North Caspian Steppe during the last 380 years. The occurrence of unique cluster of N1c-Tat haplotypes in the Khoshuuds, which dates to about 340 years and is likely to have East European ancestry, is considered as a result of interethnic contacts occurred soon after the appearance of the Kalmyk tribes in the Volga-Ural region.


Subject(s)
Asian People/genetics , Chromosomes, Human, Y/genetics , Ethnicity/genetics , Polymorphism, Genetic/genetics , White People/genetics , Gene Flow/genetics , Gene Frequency/genetics , Genetics, Population , Haplotypes , Humans , Male , Microsatellite Repeats/genetics
12.
Mol Phylogenet Evol ; 67(2): 348-57, 2013 May.
Article in English | MEDLINE | ID: mdl-23415986

ABSTRACT

We assessed phylogeny of the Siberian salamander (Salamandrella keyserlingii, Dybowski, 1870), the most northern ectothermic, terrestrial vertebrate in Eurasia, by sequence analysis of complete mitochondrial genomes in 26 specimens from different localities (China, Khabarovsk region, Sakhalin, Yakutia, Magadan region, Chukotka, Kamchatka, Ural, European part of Russia). In addition, a complete mitochondrial genome of the Schrenck salamander, Salamandrella schrenckii, was determined for the first time. Bayesian phylogenetic analysis of the entire mtDNA genomes of S. keyserlingii demonstrates that two haplotype clades, AB and C, radiated about 1.4 million years ago (Mya). Bayesian skyline plots of population size change through time show an expansion around 250 thousand years ago (kya) and then a decline around the Last Glacial Maximum (25 kya) with subsequent restoration of population size. Climatic changes during the Quaternary period have dramatically affected the population genetic structure of the Siberian salamanders. In addition, complete mtDNA sequence analysis allowed us to recognize that the vast area of Northern Eurasia was colonized only by the Siberian salamander clade C1b during the last 150 kya. Meanwhile, we were unable to find evidence of molecular adaptation in this clade by analyzing the whole mitochondrial genomes of the Siberian salamanders.


Subject(s)
Genome, Mitochondrial , Phylogeny , Urodela , Animals , Genetics, Population , Haplotypes , Russia , Sequence Analysis, DNA , Siberia , Urodela/classification , Urodela/genetics
13.
J Hum Genet ; 57(10): 685-6, 2012 Oct.
Article in English | MEDLINE | ID: mdl-22810113

ABSTRACT

As there are ambiguities in classification of the Y-chromosome haplogroup C3c, relatively frequent in populations of Northern Asia, we analyzed all three haplogroup-defining markers M48, M77 and M86 in C3-M217-individuals from Siberia, Eastern Asia and Eastern Europe. We have found that haplogroup C3c is characterized by the derived state at M48, whereas mutations at both M77 and M86 define subhaplogroup C3c1. The branch defined by M48 alone would belong to subhaplogroup C3c*, characteristic for some populations of Central and Eastern Siberia, such as Koryaks, Evens, Evenks and Yukaghirs. Subhaplogroup C3c* individuals could be considered as remnants of the Neolithic population of Siberia, based on the age of C3c*-short tandem repeat variation amounting to 4.5 ± 2.4 thousand years.


Subject(s)
Chromosomes, Human, Y/genetics , Ethnicity/genetics , Genetics, Population/methods , Haplotypes , Europe, Eastern , Asia, Eastern , Genetic Markers , Humans , Male , Minisatellite Repeats , Mutation , Phylogeny , Polymorphism, Single Nucleotide , Siberia
14.
Mol Biol Evol ; 27(10): 2220-6, 2010 Oct.
Article in English | MEDLINE | ID: mdl-20457583

ABSTRACT

To investigate diversity of mitochondrial gene pool of Tatars inhabiting the territory of the middle Volga River basin, 197 individuals from two populations representing Kazan Tatars and Mishars were subjected for analysis of mitochondrial DNA (mtDNA) control region variation. In addition, 73 mitochondrial genomes of individuals from Mishar population were sequenced completely. It was found that mitochondrial gene pool of the Volga Tatars consists of two parts, but western Eurasian component prevails considerably (84% on average) over eastern Asian one (16%). Eastern Asian mtDNAs detected in Tatars belonged to a heterogeneous set of haplogroups (A, C, D, G, M7, M10, N9a, Y, and Z), although only haplogroups A and D were revealed simultaneously in both populations. Complete mtDNA variation study revealed that the age of western Eurasian haplogroups (such as U4, HV0a, and H) is less than 18,000 years, thus suggesting re-expansion of eastern Europeans soon after the Last Glacial Maximum.


Subject(s)
DNA, Mitochondrial/genetics , Ethnicity/genetics , Genetic Variation , Phylogeny , Base Sequence , Evolution, Molecular , Genetics, Population , Haplotypes/genetics , Humans , Models, Genetic , Molecular Sequence Data , Polymorphism, Restriction Fragment Length , Russia , Sequence Analysis, DNA
15.
J Hum Genet ; 56(8): 583-8, 2011 Aug.
Article in English | MEDLINE | ID: mdl-21677663

ABSTRACT

To investigate the structure of Y chromosome haplogroups R-M207 and Q-M242 in human populations of North Asia, we have performed high-resolution genotyping using both single nucleotide polymorphisms and short tandem repeat (STR)-based approaches of 121 M207- and M242-derived samples from 885 males of 16 ethnic groups of Siberia and East Asia. As a result, the following Y chromosome haplogroups were revealed: R1b1b1-M73 (2.0%), R1b1b2-M269 (0.7%), R2-M124 (1.1%), Q1a*-MEH2 (0.5%), Q1a2-M25 (0.1%), Q1a3*-M346 (9.2%) and Q1a3a-M3 (0.2%). Despite the low coalescence age of haplogroup Q1a3*-M346, which is estimated in South Siberia as about 4.5±1.5 thousand years ago (Ka), divergence time between these Q1a3*-M346 haplotypes and Amerindian-specific haplogroup Q1a3a-M3 is equal to 13.8±3.9 Ka, pointing to a relatively recent entry date to America. In addition, unique cluster of haplotypes belonging to Q1a*-MEH2 was found in Koryaks inhabiting the Sea of Okhotsk coast (at a frequency of 10.3%). Although the level of STR diversity associated with Q1a*-MEH2 is very low, this lineage appears to be closest to the extinct Palaeo-Eskimo individuals belonging to the Saqqaq culture arisen in the New World Arctic about 5.5 Ka. This finding suggests that Q1a*-MEH2 likely traces a population migration originating in Northeast Siberia across the Bering Strait.


Subject(s)
Chromosomes, Human, Y/genetics , Genetics, Population/methods , Haplotypes/genetics , Phylogeny , Asia , Asian People/genetics , Gene Frequency , Genetic Variation , Humans , Indians, North American/ethnology , Indians, North American/genetics , Male , Microsatellite Repeats/genetics , Pedigree , Polymorphism, Single Nucleotide/genetics , Siberia/ethnology
16.
Ann Hum Genet ; 74(6): 539-46, 2010 Nov.
Article in English | MEDLINE | ID: mdl-20726964

ABSTRACT

To reconstruct the phylogenetic structure of Y-chromosome haplogroup (hg) C in populations of northern Eurasia, we have analyzed the diversity of microsatellite (STR) loci in a total sample of 413 males from 18 ethnic groups of Siberia, Eastern Asia and Eastern Europe. Analysis of SNP markers revealed that all Y-chromosomes studied belong to hg C3 and its subhaplogroups C3c and C3d, although some populations (such as Mongols and Koryaks) demonstrate a relatively high input (more than 30%) of yet unidentified C3* haplotypes. Median joining network analysis of STR haplotypes demonstrates that Y-chromosome gene pools of populations studied are characterized by the presence of DNA clusters originating from a limited number of frequent founder haplotypes. These are subhaplogroup C3d characteristic for Mongolic-speaking populations, "star cluster" in C3* paragroup, and a set of DYS19 duplicated C3c Y-chromosomes. All these DNA clusters show relatively recent coalescent times (less than 3000 years), so it is probable that founder effects, including social selection resulting in high male fertility associated with a limited number of paternal lineages, may explain the observed distribution of hg C3 lineages.


Subject(s)
Chromosomes, Human, Y/genetics , Haplotypes , Phylogeography , Ethnicity/genetics , Europe, Eastern , Asia, Eastern , Genetic Variation , Humans , Male , Microsatellite Repeats , Polymorphism, Single Nucleotide , Siberia
17.
Mol Immunol ; 46(3): 429-36, 2009 Jan.
Article in English | MEDLINE | ID: mdl-19038455

ABSTRACT

While numerous strategies have been developed to map epitope specificities for monoclonal antibodies, few have been designed for elucidating epitope specificity within complex polysera. We have developed a novel algorithm based on pattern recognition theory that can be used to characterize the breadth of epitope specificities within a polyserum based on affinity selection of random peptides. To attribute these random peptides to a specific epitope, the sequences of the affinity-selected peptides were matched against a database of random peptides selected using well-described monoclonal antibodies. To test this novel algorithm, we employed polyserum from patients infected with West Nile virus and isolated 109 unique sequences which were recognized selectively by serum from West Nile virus-infected patients but not uninfected patients. Through application of our algorithm, it was possible to match 20% of the polyserum-selected peptides to the database of peptides isolated by affinity selection using monoclonal antibodies against the virus envelope protein. Statistical analysis demonstrated that the peptides selected with the polyserum could not be attributed to the peptide database by chance. This novel algorithm provides the basis for further development of methods to characterize the breadth of epitope recognition within a complex pool of antibodies.


Subject(s)
Algorithms , Epitopes/immunology , Immune Sera/immunology , Pattern Recognition, Automated , Peptides/immunology , Peptides/isolation & purification , Amino Acid Sequence , Chromatography, Affinity , Computational Biology , Epitopes/chemistry , Humans , Molecular Sequence Data , Peptides/chemistry , West Nile Fever/immunology , West Nile virus/chemistry , West Nile virus/immunology
18.
Mol Ther Oncolytics ; 17: 278-292, 2020 Jun 26.
Article in English | MEDLINE | ID: mdl-32368616

ABSTRACT

Tumor-targeted chimeric antigen receptor (CAR)-engineered T lymphocytes (CAR-T cells) have demonstrated striking clinical success, but their use has been associated with a constellation of toxicities. A better understanding of the pathogenesis of these toxicities is required to improve the safety profile of CAR-T cells. Herein, we describe a xenograft model of off-tumor CAR-T cell-associated toxicity. Human CAR-T cells targeted against HER2 using a small-protein binding domain induced acute, dose-dependent toxicities in mice. The inclusion of a CD28 or 4-1BB co-stimulatory domain in the CAR was required to produce toxicity; however, co-stimulation through CD28 was most toxic on a per-cell basis. CAR-T cell activation in the lungs and heart was associated with a systemic cytokine storm. The severity of observed toxicities was dependent upon the peripheral blood mononuclear cell (PBMC) donor used as a T cell source and paralleled the CD4+-to-CD8+ T cell ratio in the adoptive transfer product. CD4+ CAR-T cells were determined to be the primary contributors to CAR-T cell-associated toxicity. However, donor-specific differences persisted after infusion of a purified CD4+ CAR-T cell product, indicating a role for additional variables. This work highlights the contributions of CAR-T cell-intrinsic variables to the pathogenesis of off-tumor toxicity.

19.
Mol Immunol ; 46(1): 125-34, 2008 Nov.
Article in English | MEDLINE | ID: mdl-18760481

ABSTRACT

Understanding antibody function is often enhanced by knowledge of the specific binding epitope. Here, we describe a computer algorithm that permits epitope prediction based on a collection of random peptide epitopes (mimotopes) isolated by antibody affinity purification. We applied this methodology to the prediction of epitopes for five monoclonal antibodies against the West Nile virus (WNV) E protein, two of which exhibit therapeutic activity in vivo. This strategy was validated by comparison of our results with existing F(ab)-E protein crystal structures and mutational analysis by yeast surface display. We demonstrate that by combining the results of the mimotope method with our data from mutational analysis, epitopes could be predicted with greater certainty. The two methods displayed great complementarity as the mutational analysis facilitated epitope prediction when the results with the mimotope method were equivocal and the mimotope method revealed a broader number of residues within the epitope than the mutational analysis. Our results demonstrate that the combination of these two prediction strategies provides a robust platform for epitope characterization.


Subject(s)
Algorithms , Antibodies, Monoclonal/immunology , Antibody Affinity/immunology , Computers , Epitopes/immunology , Viral Proteins/immunology , West Nile virus/immunology , Amino Acid Sequence , Epitopes/chemistry , Models, Molecular , Molecular Sequence Data , Structural Homology, Protein , Viral Proteins/chemistry
20.
Oncoimmunology ; 8(1): e1512329, 2019.
Article in English | MEDLINE | ID: mdl-30546947

ABSTRACT

Multiple immunotherapeutics have been approved for cancer patients, however advanced solid tumors are frequently refractory to treatment. We evaluated the safety and immunogenicity of a vaccination approach with multimodal oncolytic potential in non-human primates (NHP) (Macaca fascicularis). Primates received a replication-deficient adenoviral prime, boosted by the oncolytic Maraba MG1 rhabdovirus. Both vectors expressed the human MAGE-A3. No severe adverse events were observed. Boosting with MG1-MAGEA3 induced an expansion of hMAGE-A3-specific CD4+ and CD8+ T-cells with the latter peaking at remarkable levels and persisting for several months. T-cells reacting against epitopes fully conserved between simian and human MAGE-A3 were identified. Humoral immunity was demonstrated by the detection of circulating MAGE-A3 antibodies. These preclinical data establish the capacity for the Ad:MG1 vaccination to engage multiple effector immune cell populations without causing significant toxicity in outbred NHPs. Clinical investigations utilizing this program for the treatment of MAGE-A3-positive solid malignancies are underway (NCT02285816, NCT02879760).

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