Peptide name : Peptidoglycan recognition protein 1

Source/Organism : Human

Linear/Cyclic : Not found

Chirality : Not found

Peptide length: 196

C-terminal modification: Not found

N-terminal modification : Not found

Non-natural peptide information: None

Assay type : Enzyme inhibition assay

Assay time : 3–24h

Activity : Not found

Cell line : K562

Cancer type : Not specified

Other activity : Anti-bacterial activity

Amino acid composition bar chart :

Molecular mass : 21730.5571 Dalton

Aliphatic index : 0.791

Instability index : 59.5138

Hydrophobicity (GRAVY) : -0.261

Isoelectric point : 8.9181

Charge (pH 7) : 5.227

Aromaticity : 0.086

Molar extinction coefficient (cysteine, cystine): (44920, 45295)

Hydrophobic/hydrophilic ratio : 1.20224719

hydrophobic moment : 0.0438

Missing amino acid : None

Most occurring amino acid : L

Most occurring amino acid frequency : 21

Least occurring amino acid : K

Least occurring amino acid frequency : 3

Secondary structure fraction (Helix, Turn, Sheet): (0.2, 0.3, 0.3)

SMILES Notation: CC[C@H](C)[C@H](NC(=O)CNC(=O)[C@@H](NC(=O)[C@H](CO)NC(=O)[C@H](CCSC)NC(=O)[C@@H]1CCCN1C(=O)[C@H](CC(N)=O)NC(=O)[C@H](Cc1c[nH]c2ccccc12)NC(=O)[C@H](CC(C)C)NC(=O)[C@H](Cc1c[nH]cn1)NC(=O)CNC(=O)[C@H](CO)NC(=O)[C@H](Cc1c[nH]cn1)NC(=O)[C@H](C)NC(=O)CNC(=O)[C@@H](NC(=O)[C@H](Cc1ccccc1)NC(=O)[C@H](CC(N)=O)NC(=O)[C@H](Cc1c[nH]c2ccccc12)NC(=O)CNC(=O)[C@H](CCCNC(=N)N)NC(=O)CNC(=O)[C@H](CCC(=O)O)NC(=O)[C@H](Cc1ccc(O)cc1)NC(=O)[C@@H](NC(=O)[C@H](CC(C)C)NC(=O)CNC(=O)[C@H](CC(=O)O)NC(=O)[C@H](CCC(=O)O)NC(=O)CNC(=O)[C@@H](NC(=O)[C@H](CC(C)C)NC(=O)[C@H](Cc1ccccc1)NC(=O)[C@H](CC(N)=O)NC(=O)[C@H](Cc1ccc(O)cc1)NC(=O)CNC(=O)[C@@H](NC(=O)[C@H](CC(=O)O)NC(=O)[C@H](CS)NC(=O)[C@H](Cc1c[nH]c2ccccc12)NC(=O)CNC(=O)[C@H](CC(C)C)NC(=O)[C@@H](NC(=O)[C@H](CCCCN)NC(=O)[C@H](CCSC)NC(=O)[C@H](Cc1c[nH]cn1)NC(=O)[C@H](Cc1ccc(O)cc1)NC(=O)[C@H](Cc1c[nH]cn1)NC(=O)[C@H](CCC(N)=O)NC(=O)[C@@H](NC(=O)[C@H](CC(N)=O)NC(=O)[C@H](CCCNC(=N)N)NC(=O)[C@H](C)NC(=O)[C@H](CCC(N)=O)NC(=O)[C@H](CCC(N)=O)NC(=O)[C@H](CCC(N)=O)NC(=O)[C@H](CS)NC(=O)[C@H](CO)NC(=O)[C@H](C)NC(=O)[C@@H]1CCCN1C(=O)[C@@H](NC(=O)[C@H](CC(N)=O)NC(=O)[C@H](CS)NC(=O)[C@H](CO)NC(=O)[C@H](CO)NC(=O)CNC(=O)[C@H](C)NC(=O)[C@@H](NC(=O)[C@H](Cc1c[nH]cn1)NC(=O)[C@H](CO)NC(=O)[C@@H](NC(=O)[C@@H](NC(=O)[C@@H](NC(=O)[C@H](Cc1ccc(O)cc1)NC(=O)[C@H](CCCNC(=N)N)NC(=O)[C@H](CC(C)C)NC(=O)[C@@H]1CCCN1C(=O)[C@H](CC(C)C)NC(=O)[C@H](CO)NC(=O)[C@H](CC(C)C)NC(=O)[C@H](Cc1c[nH]cn1)NC(=O)[C@H](CCC(N)=O)NC(=O)[C@H](C)NC(=O)[C@H](CS)NC(=O)[C@H](CCC(=O)O)NC(=O)[C@H](CO)NC(=O)[C@H](C)NC(=O)[C@H](CC(C)C)NC(=O)[C@H](C)NC(=O)[C@H](CCCCN)NC(=O)[C@H](Cc1c[nH]c2ccccc12)NC(=O)[C@H](CCC(=O)O)NC(=O)[C@H](CC(N)=O)NC(=O)[C@H](CCCNC(=N)N)NC(=O)[C@@H]1CCCN1C(=O)[C@@H](NC(=O)[C@@H](NC(=O)[C@@H]1CCCN1C(=O)[C@H](CO)NC(=O)[C@H](CS)NC(=O)[C@H](CS)NC(=O)[C@H](C)NC(=O)[C@@H]1CCCN1C(=O)[C@H](CC(=O)O)NC(=O)[C@H](CCC(=O)O)NC(=O)[C@@H](NC(=O)[C@H](CCC(=O)O)NC(=O)[C@H](CCC(N)=O)NC(=O)[C@H](C)NC(=O)[C@H](C)NC(=O)CNC(=O)[C@H](CC(C)C)NC(=O)[C@H](CCCNC(=N)N)NC(=O)[C@H](CC(C)C)NC(=O)[C@H](CC(C)C)NC(=O)[C@H](CO)NC(=O)[C@@H]1CCCN1C(=O)[C@H](CC(C)C)NC(=O)[C@H](C)NC(=O)[C@H](Cc1c[nH]c2ccccc12)NC(=O)[C@H](C)NC(=O)[C@H](CC(C)C)NC(=O)[C@H](CC(C)C)NC(=O)[C@H](CCSC)NC(=O)[C@H](CO)NC(=O)[C@H](CCCNC(=N)N)NC(=O)[C@H](CCCNC(=N)N)NC(=O)[C@H](CO)NC(=O)[C@@H](N)CCSC)[C@@H](C)O)[C@@H](C)CC)C(C)C)C(C)C)C(C)C)C(C)C)[C@@H](C)O)[C@@H](C)O)C(C)C)[C@@H](C)O)C(C)C)[C@@H](C)CC)C(C)C)[C@@H](C)O)[C@@H](C)CC)C(=O)N[C@@H](CO)C(=O)N[C@@H](Cc1ccccc1)C(=O)N[C@@H](CCSC)C(=O)NCC(=O)N[C@@H](CC(N)=O)C(=O)N[C@@H](Cc1ccc(O)cc1)C(=O)N[C@@H](CCSC)C(=O)N[C@@H](CC(=O)O)C(=O)N[C@@H](CCCNC(=N)N)C(=O)N[C@H](C(=O)N1CCC[C@H]1C(=O)N[C@H](C(=O)N1CCC[C@H]1C(=O)N[C@@H](CCC(N)=O)C(=O)N[C@@H](C)C(=O)N[C@H](C(=O)N[C@@H](CCCNC(=N)N)C(=O)N[C@@H](C)C(=O)N[C@@H](C)C(=O)N[C@@H](CCC(N)=O)C(=O)NCC(=O)N[C@@H](CC(C)C)C(=O)N[C@@H](CC(C)C)C(=O)N[C@@H](C)C(=O)N[C@@H](CS)C(=O)NCC(=O)N[C@H](C(=O)N[C@@H](C)C(=O)N[C@@H](CCC(N)=O)C(=O)NCC(=O)N[C@@H](C)C(=O)N[C@@H](CC(C)C)C(=O)N[C@@H](CCCNC(=N)N)C(=O)N[C@@H](CO)C(=O)N[C@@H](CC(N)=O)C(=O)N[C@@H](Cc1ccc(O)cc1)C(=O)N[C@H](C(=O)N[C@@H](CC(C)C)C(=O)N[C@@H](CCCCN)C(=O)NCC(=O)N[C@@H](Cc1c[nH]cn1)C(=O)N[C@@H](CCCNC(=N)N)C(=O)N[C@@H](CC(=O)O)C(=O)N[C@H](C(=O)N[C@@H](CCC(N)=O)C(=O)N[C@@H](CCCNC(=N)N)C(=O)N[C@H](C(=O)N[C@@H](CC(C)C)C(=O)N[C@@H](CO)C(=O)N1CCC[C@H]1C(=O)NCC(=O)N[C@@H](CC(N)=O)C(=O)N[C@@H](CCC(N)=O)C(=O)N[C@@H](CC(C)C)C(=O)N[C@@H](Cc1ccc(O)cc1)C(=O)N[C@@H](Cc1c[nH]cn1)C(=O)N[C@@H](CC(C)C)C(=O)N[C@H](C(=O)N[C@@H](CCC(N)=O)C(=O)N[C@@H](CC(N)=O)C(=O)N[C@@H](Cc1c[nH]c2ccccc12)C(=O)N1CCC[C@H]1C(=O)N[C@@H](Cc1c[nH]cn1)C(=O)N[C@@H](Cc1ccc(O)cc1)C(=O)N[C@@H](CCCNC(=N)N)C(=O)N[C@@H](CO)C(=O)N1CCC[C@H]1C(=O)O)[C@@H](C)CC)[C@@H](C)O)C(C)C)C(C)C)C(C)C)[C@@H](C)CC)[C@@H](C)O)C(C)C

1 : Read CB, et al. Cutting Edge: identification of neutrophil PGLYRP1 as a ligand for TREM-1. J Immunol. 2015; 194:1417-21. doi: 10.4049/jimmunol.1402303

2 : Guan R, et al. Crystal structure of human peptidoglycan recognition protein S (PGRP-S) at 1.70 A resolution. J Mol Biol. 2005; 347:683-91. doi: 10.1016/j.jmb.2005.01.070

3 : Kang D, et al. A peptidoglycan recognition protein in innate immunity conserved from insects to humans. Proc Natl Acad Sci U S A. 1998; 95:10078-82. doi: 10.1073/pnas.95.17.10078

4 : Gerhard DS, et al. The status, quality, and expansion of the NIH full-length cDNA project: the Mammalian Gene Collection (MGC). Genome Res. 2004; 14:2121-7. doi: 10.1101/gr.2596504

5 : Sharapova TN, et al. Tag7-Mts1 Complex Induces Lymphocytes Migration via CCR5 and CXCR3 Receptors. Acta Naturae. 2018; 10:115-120.

6 : Lu X, et al. Peptidoglycan recognition proteins are a new class of human bactericidal proteins. J Biol Chem. 2006; 281:5895-907. doi: 10.1074/jbc.M511631200

7 : Yashin DV, et al. Tag7 (PGLYRP1) in Complex with Hsp70 Induces Alternative Cytotoxic Processes in Tumor Cells via TNFR1 Receptor. J Biol Chem. 2015; 290:21724-31. doi: 10.1074/jbc.M115.639732

8 : Grimwood J, et al. The DNA sequence and biology of human chromosome 19. Nature. 2004; 428:529-35. doi: 10.1038/nature02399

9 : Clark HF, et al. The secreted protein discovery initiative (SPDI), a large-scale effort to identify novel human secreted and transmembrane proteins: a bioinformatics assessment. Genome Res. 2003; 13:2265-70. doi: 10.1101/gr.1293003

10 : Sharapova TN, et al. Innate immunity protein Tag7 (PGRP-S) activates lymphocytes capable of Fasl-Fas-dependent contact killing of virus-infected cells. IUBMB Life. 2017; 69:971-977. doi: 10.1002/iub.1688

11 : Dukhanina EA, et al. A new role for PGRP-S (Tag7) in immune defense: lymphocyte migration is induced by a chemoattractant complex of Tag7 with Mts1. Cell Cycle. 2015; 14:3635-43. doi: 10.1080/15384101.2015.1104440

12 : Sharapova TN, et al. Innate Immunity Protein Tag7 Induces 3 Distinct Populations of Cytotoxic Cells That Use Different Mechanisms to Exhibit Their Antitumor Activity on Human Leukocyte Antigen-Deficient Cancer Cells. J Innate Immun. 2017; 9:598-608. doi: 10.1159/000479382

Paper title : Cutting Edge: identification of neutrophil PGLYRP1 as a ligand for TREM-1.

Doi : https://doi.org/10.4049/jimmunol.1402303

Abstract : Triggering receptor expressed on myeloid cells (TREM)-1 is an orphan receptor implicated in innate immune activation. Inhibition of TREM-1 reduces sepsis in mouse models, suggesting a role for it in immune responses triggered by bacteria. However, the absence of an identified ligand has hampered a full understanding of TREM-1 function. We identified complexes between peptidoglycan recognition protein 1 (PGLYRP1) and bacterially derived peptidoglycan that constitute a potent ligand capable of binding TREM-1 and inducing known TREM-1 functions. Interestingly, multimerization of PGLYRP1 bypassed the need for peptidoglycan in TREM-1 activation, demonstrating that the PGLYRP1/TREM-1 axis can be activated in the absence of bacterial products. The role for PGLYRP1 as a TREM-1 activator provides a new mechanism by which bacteria can trigger myeloid cells, linking two known, but previously unrelated, pathways in innate immunity.

Paper title : Crystal structure of human peptidoglycan recognition protein S (PGRP-S) at 1.70 A resolution.

Doi : https://doi.org/10.1016/j.jmb.2005.01.070

Abstract : Peptidoglycan recognition proteins (PGRPs) are pattern recognition receptors of the innate immune system that bind peptidoglycans (PGNs) of bacterial cell walls. These molecules, which are highly conserved from insects to mammals, contribute to host defense against infections by both Gram-positive and Gram-negative bacteria. Here, we present the crystal structure of human PGRP-S at 1.70A resolution. The overall structure of PGRP-S, which participates in intracellular killing of Gram-positive bacteria, is similar to that of other PGRPs, including Drosophila PGRP-LB and PGRP-SA and human PGRP-Ialpha. However, comparison with these PGRPs reveals important differences in both the PGN-binding site and a groove formed by the PGRP-specific segment on the opposite face of the molecule. This groove, which may constitute a binding site for effector or signaling proteins, is less hydrophobic and deeper in PGRP-S than in PGRP-IalphaC, whose PGRP-specific segments vary considerably in amino acid sequence. By docking a PGN ligand into the PGN-binding cleft of PGRP-S based on the known structure of a PGRP-Ialpha-PGN complex, we identified potential PGN-binding residues in PGRP-S. Differences in PGN-contacting residues and interactions suggest that, although PGRPs may engage PGNs in a similar mode, structural differences exist that likely regulate the affinity and fine specificity of PGN recognition.

Paper title : A peptidoglycan recognition protein in innate immunity conserved from insects to humans.

Doi : https://doi.org/10.1073/pnas.95.17.10078

Abstract : Innate nonself recognition must rely on common structures of invading microbes. In a differential display screen for up-regulated immune genes in the moth Trichoplusia ni we have found mechanisms for recognition of bacterial cell wall fragments. One bacteria-induced gene encodes a protein that, after expression in the baculovirus system, was shown to be a peptidoglycan recognition protein (PGRP). It binds strongly to Gram-positive bacteria. We have also cloned the corresponding cDNA from mouse and human and shown this gene to be expressed in a variety of organs, notably organs of the immune system-i.e., bone marrow and spleen. In addition, purified recombinant murine PGRP was shown to possess peptidoglycan affinity. From our results and the sequence homology, we conclude that PGRP is a ubiquitous protein involved in innate immunity, conserved from insects to humans.

Paper title : The status, quality, and expansion of the NIH full-length cDNA project: the Mammalian Gene Collection (MGC).

Doi : https://doi.org/10.1101/gr.2596504

Abstract : The National Institutes of Health's Mammalian Gene Collection (MGC) project was designed to generate and sequence a publicly accessible cDNA resource containing a complete open reading frame (ORF) for every human and mouse gene. The project initially used a random strategy to select clones from a large number of cDNA libraries from diverse tissues. Candidate clones were chosen based on 5'-EST sequences, and then fully sequenced to high accuracy and analyzed by algorithms developed for this project. Currently, more than 11,000 human and 10,000 mouse genes are represented in MGC by at least one clone with a full ORF. The random selection approach is now reaching a saturation point, and a transition to protocols targeted at the missing transcripts is now required to complete the mouse and human collections. Comparison of the sequence of the MGC clones to reference genome sequences reveals that most cDNA clones are of very high sequence quality, although it is likely that some cDNAs may carry missense variants as a consequence of experimental artifact, such as PCR, cloning, or reverse transcriptase errors. Recently, a rat cDNA component was added to the project, and ongoing frog (Xenopus) and zebrafish (Danio) cDNA projects were expanded to take advantage of the high-throughput MGC pipeline.

Paper title : Tag7-Mts1 Complex Induces Lymphocytes Migration via CCR5 and CXCR3 Receptors.

Doi : https://doi.org/Not available

Abstract : The discovery of new chemokines that induce the migration of lymphocytes to the infection site is important for the targeted search for therapeutic agents in immunotherapy. We recently showed that Tag7 (PGLYRP1), an innate immunity protein, forms a stable complex with the Ca2+ -binding protein Mts1 (S100A4), which is able to induce lymphocyte movement, although the individual Tag7 and Mts1 do not have this activity. The purpose of this study is to identify receptors that induce the migration of lymphocytes along the concentration gradient of the Tag7-Mts1 complex, and the components of this complex capable of interacting with these receptors. The study investigated the migration of human PBMC under the action of the Tag7-Mts1complex. PBMC of healthy donors were isolated using a standard Ficoll-Hypaque gradient centrifugation procedure. It has been established that the movement of PBMC along the concentration gradient of the Tag7-Mts1 complex is induced by the classical chemotactic receptors CCR5 and CXCR3. It has been shown that only Mts1 is able to bind to the extracellular domain of CCR5, however, this binding is not enough to induce cell movement. A comparative analysis of the primary and 3D structures of the three proteins revealed the homology of the amino acid sequence fragments of the Tag7-Mts1 protein complex with different sites of the CCR5 receptor ligand - MIP1α protein. In conclusion, it should be noted that the Tag7-Mts1 complex can be considered as a new ligand of the classical chemotactic receptors CCR5 and CXCR3.

Paper title : Peptidoglycan recognition proteins are a new class of human bactericidal proteins.

Doi : https://doi.org/10.1074/jbc.M511631200

Abstract : Skin and mucous membranes come in contact with external environment and protect tissues from infections by producing antimicrobial peptides. We report that human peptidoglycan recognition proteins 3 and 4 (PGLYRP3 and PGLYRP4) are secreted as 89-115-kDa disulfide-linked homo- and heterodimers and are bactericidal against several pathogenic and nonpathogenic transient, but not normal flora, Gram-positive bacteria. PGLYRP3 and PGLYRP4 are also bacteriostatic toward all other tested bacteria, which include Gram-negative bacteria and normal flora Gram-positive bacteria. PGLYRP3 and PGLYRP4 are also active in vivo and protect mice against experimental lung infection. In contrast to antimicrobial peptides, PGLYRPs kill bacteria by interacting with their cell wall peptidoglycan, rather than permeabilizing their membranes. PGLYRP3 and PGLYRP4 are expressed in the skin, eyes, salivary glands, throat, tongue, esophagus, stomach, and intestine. Thus, we have identified the function of mammalian PGLYRP3 and PGLYRP4, and show that they are a new class of bactericidal and bacteriostatic proteins that have different structures, mechanism of actions, and expression patterns than antimicrobial peptides.

Paper title : Tag7 (PGLYRP1) in Complex with Hsp70 Induces Alternative Cytotoxic Processes in Tumor Cells via TNFR1 Receptor.

Doi : https://doi.org/10.1074/jbc.M115.639732

Abstract : Tag7 (also known as peptidoglycan recognition protein PGRP-S, PGLYRP1), an innate immunity protein, interacts with Hsp70 to form a stable Tag7-Hsp70 complex with cytotoxic activity against some tumor cell lines. In this study, we have analyzed the programmed cell death mechanisms that are induced when cells interact with the Tag7-Hsp70 complex, which was previously shown to be released by human lymphocytes and is cytotoxic to cancer cells. We show that this complex induces both apoptotic and necroptotic processes in the cells. Apoptosis follows the classic caspase-8 and caspase-3 activation pathway. Inhibition of apoptosis leads to a switch to the RIP1-dependent necroptosis. Both of these cytotoxic processes are initiated by the involvement of TNFR1, a receptor for TNF-α. Our results suggest that the Tag7-Hsp70 complex is a novel ligand for this receptor. One of its components, the innate immunity protein Tag7, can bind to the TNFR1 receptor, thereby inhibiting the cytotoxic actions of the Tag7-Hsp70 complex and TNF-α, an acquired immunity cytokine.

Paper title : The DNA sequence and biology of human chromosome 19.

Doi : https://doi.org/10.1038/nature02399

Abstract : Chromosome 19 has the highest gene density of all human chromosomes, more than double the genome-wide average. The large clustered gene families, corresponding high G + C content, CpG islands and density of repetitive DNA indicate a chromosome rich in biological and evolutionary significance. Here we describe 55.8 million base pairs of highly accurate finished sequence representing 99.9% of the euchromatin portion of the chromosome. Manual curation of gene loci reveals 1,461 protein-coding genes and 321 pseudogenes. Among these are genes directly implicated in mendelian disorders, including familial hypercholesterolaemia and insulin-resistant diabetes. Nearly one-quarter of these genes belong to tandemly arranged families, encompassing more than 25% of the chromosome. Comparative analyses show a fascinating picture of conservation and divergence, revealing large blocks of gene orthology with rodents, scattered regions with more recent gene family expansions and deletions, and segments of coding and non-coding conservation with the distant fish species Takifugu.

Paper title : The secreted protein discovery initiative (SPDI), a large-scale effort to identify novel human secreted and transmembrane proteins: a bioinformatics assessment.

Doi : https://doi.org/10.1101/gr.1293003

Abstract : A large-scale effort, termed the Secreted Protein Discovery Initiative (SPDI), was undertaken to identify novel secreted and transmembrane proteins. In the first of several approaches, a biological signal sequence trap in yeast cells was utilized to identify cDNA clones encoding putative secreted proteins. A second strategy utilized various algorithms that recognize features such as the hydrophobic properties of signal sequences to identify putative proteins encoded by expressed sequence tags (ESTs) from human cDNA libraries. A third approach surveyed ESTs for protein sequence similarity to a set of known receptors and their ligands with the BLAST algorithm. Finally, both signal-sequence prediction algorithms and BLAST were used to identify single exons of potential genes from within human genomic sequence. The isolation of full-length cDNA clones for each of these candidate genes resulted in the identification of >1000 novel proteins. A total of 256 of these cDNAs are still novel, including variants and novel genes, per the most recent GenBank release version. The success of this large-scale effort was assessed by a bioinformatics analysis of the proteins through predictions of protein domains, subcellular localizations, and possible functional roles. The SPDI collection should facilitate efforts to better understand intercellular communication, may lead to new understandings of human diseases, and provides potential opportunities for the development of therapeutics.

Paper title : Innate immunity protein Tag7 (PGRP-S) activates lymphocytes capable of Fasl-Fas-dependent contact killing of virus-infected cells.

Doi : https://doi.org/10.1002/iub.1688

Abstract : The innate immunity protein Tag7 (PGRP-S, PGLYRP1) is involved in antimicrobial and antitumor defense. As shown in our previous studies, Tag7 specifically interacts with the major heat shock protein Hsp70 to form a stable Tag7-Hsp70 complex with cytotoxic activity against tumor cells. A stable complex of Tag7 with the calcium-binding protein Mts1 (S100A4) stimulates migration of lymphocytes. Moreover, Tag7 can activate cytotoxic lymphocytes that recognize and kill HLA-negative tumor cells. Here, we have shown that Tag 7 treatment of human peripheral blood mononuclear cells (PBMCs) results in activation of different cytotoxic lymphocyte populations-natural killer (NK) cells and CD8+ NKG2D+ T lymphocytes-that kill Moloney murine leukemia virus (MMLV) infected SC-1 cells using different mechanisms of cell death induction. This mechanism in NK cells is based on the release of granzymes, which activate apoptosis in target cells, while CD8+ NKG2D+ T lymphocytes recognize the noncanonical MicA antigen on the surface of virus-containing cells and kill them via the FasL-Fas interaction, triggering the apoptotic or necroptotic cell death pathway. Preliminary incubation of PBMCs with virus-infected cells and following incubation with Tag7 results in activation of lymphocytes with a different phenotype. These lymphocytes change the spectrum of target cells and the mechanism of cell death induction, and their interaction with target cells is not species-specific. © 2017 IUBMB Life, 69(12):971-977, 2017.

Paper title : A new role for PGRP-S (Tag7) in immune defense: lymphocyte migration is induced by a chemoattractant complex of Tag7 with Mts1.

Doi : https://doi.org/10.1080/15384101.2015.1104440

Abstract : PGRP-S (Tag7) is an innate immunity protein involved in the antimicrobial defense systems, both in insects and in mammals. We have previously shown that Tag7 specifically interacts with several proteins, including Hsp70 and the calcium binding protein S100A4 (Mts1), providing a number of novel cellular functions. Here we show that Tag7-Mts1 complex causes chemotactic migration of lymphocytes, with NK cells being a preferred target. Cells of either innate immunity (neutrophils and monocytes) or acquired immunity (CD4(+) and CD8(+) lymphocytes) can produce this complex, which confirms the close connection between components of the 2 branches of immune response.

Paper title : Innate Immunity Protein Tag7 Induces 3 Distinct Populations of Cytotoxic Cells That Use Different Mechanisms to Exhibit Their Antitumor Activity on Human Leukocyte Antigen-Deficient Cancer Cells.

Doi : https://doi.org/10.1159/000479382

Abstract : The search for new immune response mechanisms capable of controlling immune-evasive tumor cells devoid of the MHC antigen is a challenging task for immunologists. In this study, we found that the treatment of human peripheral blood lymphocytes with the innate immunity protein Tag7 (PGRP-S, PGLYRP1) induces differentiation of the populations of NK (natural killer) cells and CD8+ and CD4+ T lymphocytes that are cytotoxic for human leukocyte antigen-negative tumor cells. These populations employ different mechanisms of tumor cell lysis (based on the release of granzymes in the case of NK cells and on the FasL-Fas interaction in the case of CD8+ and CD4+ T lymphocytes) and induce different death pathways (apoptosis or necroptosis) in tumor cells. An analysis of genes activated in leukocyte populations after Tag7 treatment and experiments with specific inhibitors have shown that the TREM-1 receptor expressed on the monocyte cell surface is essential for activation of cytotoxic activity. Overall, the results of this study provide evidence for a novel role of the Tag7 protein in the immune response.