Universal germline genetic testing in patients with hematologic malignancies using DNA isolated from nail clippings.

Not available.

Glutathione-dependent depalmitoylation of phospholemman by peroxiredoxin 6.

Phospholemman (PLM) regulates the cardiac sodium pump: PLM phosphorylation activates the pump whereas PLM palmitoylation inhibits its activity. Here, we show that the anti-oxidant protein peroxiredoxin 6 (Prdx6) interacts with and depalmitoylates PLM in a glutathione-dependent manner. Glutathione loading cells acutely reduce PLM palmitoylation; glutathione depletion significantly increases PLM palmitoylation. Prdx6 silencing abolishes these effects, suggesting that PLM can be depalmitoylated by reduced Prdx6. In vitro, only recombinant Prdx6, among several peroxiredoxin isoforms tested, removes palmitic acid from recombinant palmitoylated PLM. The broad-spectrum depalmitoylase inhibitor palmostatin B prevents Prdx6-dependent PLM depalmitoylation in cells and in vitro. Our data suggest that Prdx6 is a thioesterase that can depalmitoylate proteins by nucleophilic attack via its reactive thiol, linking PLM palmitoylation and hence sodium pump activity to cellular glutathione status. We show that protein depalmitoylation can occur via a catalytic cysteine in which substrate specificity is determined by a protein-protein interaction.

Talking numbers: how women and providers use risk scores during and after risk counseling - a qualitative investigation from the NRG Oncology/NSABP DMP-1 study.

OBJECTIVES: Little research exists on how risk scores are used in counselling. We examined (a) how Breast Cancer Risk Assessment Tool (BCRAT) scores are presented during counselling; (b) how women react and (c) discuss them afterwards. DESIGN: Consultations were video-recorded and participants were interviewed after the consultation as part of the NRG Oncology/National Surgical Adjuvant Breast and Bowel Project Decision-Making Project 1 (NSABP DMP-1). SETTING: Two NSABP DMP-1 breast cancer care centres in the USA: one large comprehensive cancer centre serving a high-risk population and an academic safety-net medical centre in an urban setting. PARTICIPANTS: Thirty women evaluated for breast cancer risk and their counselling providers were included. METHODS: Participants who were identified as at increased risk of breast cancer were recruited to participate in qualitative study with a video-recorded consultation and subsequent semi-structured interview that included giving feedback and input after viewing their own consultation. Consultation videos were summarised jointly and inductively as a team.tThe interview material was searched deductively for text segments that contained the inductively derived themes related to risk assessment. Subgroup analysis according to demographic variables such as age and Gail score were conducted, investigating reactions to risk scores and contrasting and comparing them with the pertinent video analysis data. From this, four descriptive categories of reactions to risk scores emerged. The descriptive categories were clearly defined after 19 interviews; all 30 interviews fit principally into one of the four descriptive categories. RESULTS: Risk scores were individualised and given meaning by providers through: (a) presenting thresholds, (b) making comparisons and (c) emphasising or minimising the calculated risk. The risk score information elicited little reaction from participants during consultations, though some added to, agreed with or qualified the provider's information. During interviews, participants reacted to the numbers in four primary ways: (a) engaging easily with numbers; (b) expressing greater anxiety after discussing the risk score; (c) accepting the risk score and (d) not talking about the risk score. CONCLUSIONS: Our study highlights the necessity that patients' experiences must be understood and put into relation to risk assessment information to become a meaningful treatment decision-making tool, for instance by categorising patients' information engagement into types. TRIAL REGISTRATION NUMBER: NCT01399359.

Genomic signature of Fanconi anaemia DNA repair pathway deficiency in cancer.

Fanconi anaemia (FA), a model syndrome of genome instability, is caused by a deficiency in DNA interstrand crosslink repair resulting in chromosome breakage1-3. The FA repair pathway protects against endogenous and exogenous carcinogenic aldehydes4-7. Individuals with FA are hundreds to thousands fold more likely to develop head and neck (HNSCC), oesophageal and anogenital squamous cell carcinomas8 (SCCs). Molecular studies of SCCs from individuals with FA (FA SCCs) are limited, and it is unclear how FA SCCs relate to sporadic HNSCCs primarily driven by tobacco and alcohol exposure or infection with human papillomavirus9 (HPV). Here, by sequencing genomes and exomes of FA SCCs, we demonstrate that the primary genomic signature of FA repair deficiency is the presence of high numbers of structural variants. Structural variants are enriched for small deletions, unbalanced translocations and fold-back inversions, and are often connected, thereby forming complex rearrangements. They arise in the context of TP53 loss, but not in the context of HPV infection, and lead to somatic copy-number alterations of HNSCC driver genes. We further show that FA pathway deficiency may lead to epithelial-to-mesenchymal transition and enhanced keratinocyte-intrinsic inflammatory signalling, which would contribute to the aggressive nature of FA SCCs. We propose that the genomic instability in sporadic HPV-negative HNSCC may arise as a result of the FA repair pathway being overwhelmed by DNA interstrand crosslink damage caused by alcohol and tobacco-derived aldehydes, making FA SCC a powerful model to study tumorigenesis resulting from DNA-crosslinking damage.

Psychosocial interventions and needs among individuals and families with Li-Fraumeni syndrome: A scoping review.

Li-Fraumeni syndrome (LFS), a rare cancer predisposition syndrome caused by germline mutations in the TP53 gene, is associated with significant lifetime risk of developing cancer and warrants extensive and long-term surveillance. There are psychosocial impacts on individuals and families living with this condition, from the initial diagnosis throughout multiple stages across the lifespan, but these impacts have not been systematically reviewed and organized. The objective of this scoping review was to synthesize and characterize the literature on psychosocial screening and outcomes, educational needs, support services, and available interventions for patients and families with LFS. A systematic search of six databases was most recently conducted in August 2020: (PubMed/MEDLINE (NLM), EMBASE (Elsevier), Cochrane Library (Wiley), CINAHL (EBSCO), PsycINFO (OVID), and Web of Science (Clarivate Analytics). A total of 15 757 titles were screened, and 24 articles included. Several important themes were identified across studies: factors associated with TP53 genetic testing, LFS surveillance, psychological outcomes, and communication. Findings related to these themes were organized into age-specific categories (age agnostic/across the lifespan, childhood, adolescence and young adulthood, and adulthood).

Prevalence and Characterization of Biallelic and Monoallelic NTHL1 and MSH3 Variant Carriers From a Pan-Cancer Patient Population.

NTHL1 and MSH3 have been implicated as autosomal recessive cancer predisposition genes. Although individuals with biallelic NTHL1 and MSH3 pathogenic variants (PVs) have increased cancer and polyposis risk, risks for monoallelic carriers are uncertain. We sought to assess the prevalence and characterize NTHL1 and MSH3 from a large pan-cancer patient population. MATERIALS AND METHODS: Patients with pan-cancer (n = 11,081) underwent matched tumor-normal sequencing with consent for germline analysis. Medical records and tumors were reviewed and analyzed. Prevalence of PVs was compared with reference controls (Genome Aggregation Database). RESULTS: NTHL1-PVs were identified in 40 patients including 39 monoallelic carriers (39/11,081 = 0.35%) and one with biallelic variants (1/11,081 = 0.009%) and a diagnosis of isolated early-onset breast cancer. NTHL1-associated mutational signature 30 was identified in the tumors of the biallelic patient and two carriers. Colonic polyposis was not identified in any NTHL1 patient. MSH3-PVs were identified in 13 patients, including 12 monoallelic carriers (12/11,081 = 0.11%) and one with biallelic MSH3 variants (1/11,081 = 0.009%) and diagnoses of later-onset cancers, attenuated polyposis, and abnormal MSH3-protein expression. Of the 12 MSH3 carriers, two had early-onset cancer diagnoses with tumor loss of heterozygosity of the wild-type MSH3 allele. Ancestry-specific burden tests demonstrated that NTHL1 and MSH3 prevalence was not significantly different in this pan-cancer population versus controls. CONCLUSION: NTHL1 and MSH3 germline alterations were not enriched in this pan-cancer patient population. However, tumor-specific findings, such as mutational signature 30 and loss of heterozygosity of the wild-type allele, suggest the potential contribution of monoallelic variants to tumorigenesis in a subset of patients.

Prospective pan-cancer germline testing using MSK-IMPACT informs clinical translation in 751 patients with pediatric solid tumors.

The spectrum of germline predisposition in pediatric cancer continues to be realized. Here we report 751 solid tumor patients who underwent prospective matched tumor-normal DNA sequencing and downstream clinical use (clinicaltrials.gov NCT01775072). Germline pathogenic and likely pathogenic (P/LP) variants were reported. One or more P/LP variants were found in 18% (138/751) of individuals when including variants in low, moderate, and high penetrance dominant or recessive genes, or 13% (99/751) in moderate and high penetrance dominant genes. 34% of high or moderate penetrance variants were unexpected based on the patient's diagnosis and previous history. 76% of patients with positive results completed a clinical genetics visit, and 21% had at least one relative undergo cascade testing as a result of this testing. Clinical actionability additionally included screening, risk reduction in relatives, reproductive use, and use of targeted therapies. Germline testing should be considered for all children with cancer.

Esophageal cancer as initial presentation of Fanconi anemia in patients with a hypomorphic FANCA variant.

Fanconi anemia (FA) is a clinically heterogenous and genetically diverse disease with 22 known complementation groups (FA-A to FA-W), resulting from the inability to repair DNA interstrand cross-links. This rare disorder is characterized by congenital defects, bone marrow failure, and cancer predisposition. FANCA is the most commonly mutated gene in FA and a variety of mostly private mutations have been documented, including small and large indels and point and splicing variants. Genotype-phenotype associations in FA are complex, and a relationship between particular FANCA variants and the observed cellular phenotype or illness severity remains unclear. In this study, we describe two siblings with compound heterozygous FANCA variants (c.3788_3790delTCT and c.4199G > A) who both presented with esophageal squamous cell carcinoma at the age of 51. The proband came to medical attention when he developed pancytopenia after a single cycle of low-dose chemotherapy including platinum-based therapy. Other than a minor thumb abnormality, neither patient had prior findings to suggest FA, including normal blood counts and intact fertility. Patient fibroblasts from both siblings display increased chromosomal breakage and hypersensitivity to interstrand cross-linking agents as seen in typical FA. Based on our functional data demonstrating that the c.4199G > A/p.R1400H variant represents a hypomorphic FANCA allele, we conclude that the residual activity of the Fanconi anemia repair pathway accounts for lack of spontaneous bone marrow failure or infertility with the late presentation of malignancy as the initial disease manifestation. This and similar cases of adult-onset esophageal cancer stress the need for chromosome breakage testing in patients with early onset of aerodigestive tract squamous cell carcinomas before platinum-based therapy is initiated.

Control of protein palmitoylation by regulating substrate recruitment to a zDHHC-protein acyltransferase.

Although palmitoylation regulates numerous cellular processes, as yet efforts to manipulate this post-translational modification for therapeutic gain have proved unsuccessful. The Na-pump accessory sub-unit phospholemman (PLM) is palmitoylated by zDHHC5. Here, we show that PLM palmitoylation is facilitated by recruitment of the Na-pump α sub-unit to a specific site on zDHHC5 that contains a juxtamembrane amphipathic helix. Site-specific palmitoylation and GlcNAcylation of this helix increased binding between the Na-pump and zDHHC5, promoting PLM palmitoylation. In contrast, disruption of the zDHHC5-Na-pump interaction with a cell penetrating peptide reduced PLM palmitoylation. Our results suggest that by manipulating the recruitment of specific substrates to particular zDHHC-palmitoyl acyl transferases, the palmitoylation status of individual proteins can be selectively altered, thus opening the door to the development of molecular modulators of protein palmitoylation for the treatment of disease.

11p15.5 epimutations in children with Wilms tumor and hepatoblastoma detected in peripheral blood.

BACKGROUND: Constitutional or somatic mosaic epimutations are increasingly recognized as a mechanism of gene dysregulation resulting in cancer susceptibility. Beckwith-Wiedemann syndrome is the cancer predisposition syndrome most commonly associated with epimutation and is extremely variable in its phenotypic presentation, which can include isolated tumors. Because to the authors' knowledge large-scale germline DNA sequencing studies have not included methylation analysis, the percentage of pediatric cancer predisposition that is due to epimutations is unknown. METHODS: Germline methylation testing at the 11p15.5 locus was performed in blood for 24 consecutive patients presenting with hepatoblastoma (3 patients) or Wilms tumor (21 patients). RESULTS: Six individuals with Wilms tumor and 1 patient with hepatoblastoma were found to have low-level gain of methylation at imprinting control 1, and a child with hepatoblastoma was found to have loss of methylation at imprinting control 2. The loss of methylation at imprinting control 2 was found to be maternally inherited, despite not being associated with any detectable genomic alteration. CONCLUSIONS: Overall, 33% of patients (8 of 24 patients) with Wilms tumor or hepatoblastoma were found to have an epigenetic susceptibility that was detectable in the blood. It is interesting to note that low-level gain of methylation at imprinting control 1 predominantly was detected in females with bilateral Wilms tumors. Further studies in larger cohorts are needed to determine the efficacy of testing all patients with Wilms tumor or hepatoblastoma for 11p15.5 epimutations in the blood as part of DNA analysis because this hallmark of predisposition will not be detected by sequencing-based approaches and detecting a cancer predisposition may modify treatment.

Germline SDHA mutations in children and adults with cancer.

Mutations in succinate dehydrogenase complex genes predispose to familial paraganglioma-pheochromocytoma syndrome (FPG) and gastrointestinal stromal tumors (GIST). Here we describe cancer patients undergoing agnostic germline testing at Memorial Sloan Kettering Cancer Center and found to harbor germline SDHA mutations. Using targeted sequencing covering the cancer census genes, we identified 10 patients with SDHA germline mutations. Cancer diagnoses for these patients carrying SDHA germline mutations included neuroblastoma (n = 1), breast (n = 1), colon (n = 1), renal (n = 1), melanoma and uterine (n = 1), prostate (n = 1), endometrial (n = 1), bladder (n = 1), and gastrointestinal stromal tumor (GIST) (n = 2). Immunohistochemical staining and assessment of patient tumors for second hits and loss of heterozygosity in SDHA confirmed GIST as an SDHA-associated tumor and suggests SDHA germline mutations may be a driver in neuroblastoma tumorigenesis.

Germline BRCA2 mutations detected in pediatric sequencing studies impact parents' evaluation and care.

There has been no indication to test for BRCA1/2 in children (with the rare exception of Fanconi anemia) as screening begins in adult years and there is a potential to induce anxiety related to adult-onset cancers. However, in the setting of pediatric cancer, with increasing utility and frequency of companion tumor-normal sequencing without regard for phenotype and with BRCA1/2 included in tumor profiling panels, germline mutations in BRCA1/2 and other DNA damage repair genes have been found. When mutations in these genes are revealed, there are implications for immediate family members. Here we present two children in whom BRCA2 mutations identified through tumor sequencing prompted parental genetic testing and medical action. These cases illustrate the potential importance of including a matched normal DNA sample when performing tumor profiling of pediatric cancer patients to ensure optimal care.

An amphipathic α-helix directs palmitoylation of the large intracellular loop of the sodium/calcium exchanger.

The electrogenic sodium/calcium exchanger (NCX) mediates bidirectional calcium transport controlled by the transmembrane sodium gradient. NCX inactivation occurs in the absence of phosphatidylinositol 4,5-bisphosphate and is facilitated by palmitoylation of a single cysteine at position 739 within the large intracellular loop of NCX. The aim of this investigation was to identify the structural determinants of NCX1 palmitoylation. Full-length NCX1 (FL-NCX1) and a YFP fusion protein of the NCX1 large intracellular loop (YFP-NCX1) were expressed in HEK cells. Single amino acid changes around Cys-739 in FL-NCX1 and deletions on the N-terminal side of Cys-739 in YFP-NCX1 did not affect NCX1 palmitoylation, with the exception of the rare human polymorphism S738F, which enhanced FL-NCX1 palmitoylation, and D741A, which modestly reduced it. In contrast, deletion of a 21-amino acid segment enriched in aromatic amino acids on the C-terminal side of Cys-739 abolished YFP-NCX1 palmitoylation. We hypothesized that this segment forms an amphipathic α-helix whose properties facilitate Cys-739 palmitoylation. Introduction of negatively charged amino acids to the hydrophobic face or of helix-breaking prolines impaired palmitoylation of both YFP-NCX1 and FL-NCX1. Alanine mutations on the hydrophilic face of the helix significantly reduced FL-NCX1 palmitoylation. Of note, when the helix-containing segment was introduced adjacent to cysteines that are not normally palmitoylated, they became palmitoylation sites. In conclusion, we have identified an amphipathic α-helix in the NCX1 large intracellular loop that controls NCX1 palmitoylation. NCX1 palmitoylation is governed by a distal secondary structure element rather than by local primary sequence.

Intracardiac Low-grade Sarcoma Following Treatment for Ewing Sarcoma.

A 16-year-old male was diagnosed with Ewing sarcoma of the ribcage with pulmonary metastases. Six months after completion of scheduled therapy, he was found to have a new intracardiac mass, presumed recurrent Ewing sarcoma. EWSR1 fusion was not detected by droplet digital polymerase chain reaction from blood plasma. After no improvement with salvage chemotherapy, he underwent surgical resection that identified a low-grade spindle cell sarcoma. Despite the near-synchronous presentation of 2 unrelated sarcomas, extensive genomic analyses did not reveal any unifying somatic or germline mutations nor any apparent cancer predisposition. This case also highlights the potential role of utilizing plasma cell-free DNA for diagnosing tumors in locations where biopsy confers high morbidity.

Natural history and management of Fanconi anemia patients with head and neck cancer: A 10-year follow-up.

OBJECTIVES/HYPOTHESIS: To describe the management and outcomes of Fanconi anemia (FA) patients with head and neck squamous cell carcinoma. STUDY DESIGN: Cohort study. METHODS: Demographic information, prognostic factors, therapeutic management, and survival outcomes for FA patients enrolled in the International Fanconi Anemia Registry who developed head and neck squamous cell carcinoma (HNSCC) were analyzed. RESULTS: Thirty-five FA patients were diagnosed with HNSCC at a mean age of 32 years. The most common site of primary cancer was the oral cavity (26 of 35, 74%). Thirty patients underwent surgical resection of the cancer. Sixteen patients received radiation therapy with an average radiation dose of 5,050 cGy. The most common toxicities were high-grade mucositis (9 of 16, 56%), hematologic abnormalities (8 of 16, 50%), and dysphagia (8 of 16, 50%). Three patients received conventional chemotherapy and had significant complications, whereas three patients who received targeted chemotherapy with cetuximab had fewer toxicities. The 5-year overall survival rate was 39%, with a cause-specific survival rate of 47%. CONCLUSIONS: Fanconi anemia patients have a high risk of developing aggressive HNSCC at an early age. Fanconi anemia patients can tolerate complex ablative and reconstructive surgeries, but careful postoperative care is required to reduce morbidity. The treatment of FA-associated HNSCC is difficult secondary to the poor tolerance of radiation and chemotherapy. However, radiation should be used for high-risk cancers due to the poor survival in these patients. LEVEL OF EVIDENCE: 4.

Deficiency of UBE2T, the E2 Ubiquitin Ligase Necessary for FANCD2 and FANCI Ubiquitination, Causes FA-T Subtype of Fanconi Anemia.

Fanconi anemia (FA) is a rare bone marrow failure and cancer predisposition syndrome resulting from pathogenic mutations in genes encoding proteins participating in the repair of DNA interstrand crosslinks (ICLs). Mutations in 17 genes (FANCA-FANCS) have been identified in FA patients, defining 17 complementation groups. Here, we describe an individual presenting with typical FA features who is deficient for the ubiquitin-conjugating enzyme (E2), UBE2T. UBE2T is known to interact with FANCL, the E3 ubiquitin-ligase component of the multiprotein FA core complex, and is necessary for the monoubiquitination of FANCD2 and FANCI. Proband fibroblasts do not display FANCD2 and FANCI monoubiquitination, do not form FANCD2 foci following treatment with mitomycin C, and are hypersensitive to crosslinking agents. These cellular defects are complemented by expression of wild-type UBE2T, demonstrating that deficiency of the protein UBE2T can lead to Fanconi anemia. UBE2T gene gains an alias of FANCT.

TGF-beta1-Induced MAPK activation promotes collagen synthesis, nodule formation, redox stress and cellular senescence in porcine aortic valve interstitial cells.

BACKGROUND AND AIM OF THE STUDY: Aortic valve stenosis is a major cause of valve replacement, particularly in the elderly. TGF-beta1 is upregulated in stenotic valves and induces calcification and collagen synthesis in cultured valve interstitial cells. It has been shown previously that TGF-beta1 increases reactive oxygen species (ROS) in these cells in association with calcifying nodule formation, but the cellular signaling pathways responsible for these TGF-beta1-induced effects are not well defined. METHODS: Cultured porcine aortic valve interstitial cells were used to investigate the effects of inhibitors of TGF-beta1 signaling pathways on 3H-proline incorporation into the extracellular matrix, the peak number of calcifying nodules formed, redox stress as dichlorofluorescein diacetate (DCF-DA) fluorescence, and senescence-associated beta-galactosidase staining. RESULTS: Nodule formation and proline incorporation were inhibited by SB431542, implicating the Smad pathway, by SB203580, implicating the P38 MAPK pathway, and by U0126, implicating the Mekl/2/Erk1/2 pathway in both processes. Fasudil, an inhibitor of the Rho kinase pathway, was selective in inhibiting nodule formation but not proline incorporation. It was verified that Smad2 phosphorylation, Erk1/2 phosphorylation and p38 MAPK phosphorylation were all induced by TGF-beta1, with Smad 2 phosphorylation peaking at 1-2 h and MAPK phosphorylation at 24-48 h. The effect of TGF-beta1 on phosphorylation of Smad 2 was inhibited by SB431542, on the phosphorylation of p38 MAPK was inhibited by SB203580, and on the phosphorylation of Erk1/2 was inhibited by U0126. ROS generation in response to TGF-beta1, measured as 2,7-dichlorofluorescein-diacetate fluorescence, was inhibited significantly by SB203580 and U0126, implicating both the p38 MAPK and Mekl/2/Erk1/2 signaling pathways. Both pathways also mediated TGF-beta1-induced cellular senescence which was localized to cellular aggregates and mature nodules. CONCLUSION: These data imply that the inhibition of either Smad or MAPK signaling pathways may have a therapeutic benefit in ameliorating the adverse pathological changes associated with aortic valve stenosis.

Ubiquitin C-terminal hydrolase l1 in tumorigenesis.

Ubiquitin carboxyl-terminal hydrolase L1 (UCH-L1, aka PGP9.5) is an abundant, neuronal deubiquitinating enzyme that has also been suggested to possess E3 ubiquitin-protein ligase activity and/or stabilize ubiquitin monomers in vivo. Recent evidence implicates dysregulation of UCH-L1 in the pathogenesis and progression of human cancers. Although typically only expressed in neurons, high levels of UCH-L1 have been found in many nonneuronal tumors, including breast, colorectal, and pancreatic carcinomas. UCH-L1 has also been implicated in the regulation of metastasis and cell growth during the progression of nonsmall cell lung carcinoma, colorectal cancer, and lymphoma. Together these studies suggest UCH-L1 has a potent oncogenic role and drives tumor development. Conversely, others have observed promoter methylation-mediated silencing of UCH-L1 in certain tumor subtypes, suggesting a potential tumor suppressor role for UCH-L1. In this paper, we provide an overview of the evidence supporting the involvement of UCH-L1 in tumor development and discuss the potential mechanisms of action of UCH-L1 in oncogenesis.

Plasticity of Ly-6C(hi) myeloid cells in T cell regulation.

CD11b(+)Ly-6C(hi) cells, including inflammatory monocytes (IMCs) and inflammatory dendritic cells (IDCs), are important in infectious, autoimmune, and tumor models. However, their role in T cell regulation is controversial. In this article, we show that T cell regulation by IMCs and IDCs is determined by their activation state and is plastic during an immune response. Nonactivated IMCs and IDCs function as APCs, but activated IMCs and IDCs suppress T cells through NO production. Suppressive IMCs are induced by IFN-γ, GM-CSF, TNF-α, and CD154 derived from activated T cells during their interaction. In experimental autoimmune encephalomyelitis, CD11b(+)Ly-6C(hi) cells in the CNS are increasingly activated from disease onset to peak and switch their function from Ag presentation to T cell suppression. Furthermore, transfer of activated IMCs or IDCs enhances T cell apoptosis in the CNS and suppresses experimental autoimmune encephalomyelitis. These data highlight the interplay between innate and adaptive immunity: immunization leads to the expansion of Ly-6C(hi) myeloid cells initially promoting T cell function. As T cells become highly activated in the target tissue, they induce activation and NO production in Ly-6C(hi) myeloid cells, which in turn suppress T cells and lead to the contraction of local immune response.