Human adipose tissue as a major reservoir of cytomegalovirus-reactive T cells.

Introduction: Cytomegalovirus (CMV) is a common herpesvirus with a high prevalence worldwide. After the acute infection phase, CMV can remain latent in several tissues. CD8 T cells in the lungs and salivary glands mainly control its reactivation control. White adipose tissue (WAT) contains a significant population of memory T cells reactive to viral antigens, but CMV specificity has mainly been studied in mouse WAT. Therefore, we obtained blood, omental WAT (oWAT), subcutaneous WAT (sWAT), and liver samples from 11 obese donors to characterize the human WAT adaptive immune landscape from a phenotypic and immune receptor specificity perspective. Methods: We performed high-throughput sequencing of the T cell receptor (TCR) locus to analyze tissue and blood TCR repertoires of the 11 donors. The presence of TCRs specific to CMV epitopes was tested through ELISpot assays. Moreover, phenotypic characterization of T cells was carried out through flow cytometry. Results: High-throughput sequencing analyses revealed that tissue TCR repertoires in oWAT, sWAT, and liver samples were less diverse and dominated by hyperexpanded clones when compared to blood samples. Additionally, we predicted the presence of TCRs specific to viral epitopes, particularly from CMV, which was confirmed by ELISpot assays. Remarkably, we found that oWAT has a higher proportion of CMV-reactive T cells than blood or sWAT. Finally, flow cytometry analyses indicated that most WAT-infiltrated lymphocytes were tissue-resident effector memory CD8 T cells. Discussion: Overall, these findings postulate human oWAT as a major reservoir of CMV-specific T cells, presumably for latent viral reactivation control. This study enhances our understanding of the adaptive immune response in human WAT and highlights its potential role in antiviral defense.

High incidence of CTLA-4 AA (CT60) polymorphism in renal cell cancer.

Polymorphism in genes encoding T-cell regulatory proteins and cytokines may influence inflammation and cancer development via regulation of antitumor immune response. In the current study we analyzed genotypic frequencies of cytotoxic T-lymphocyte antigen-4 (CTLA-4)/CT60, CTLA-4/A49G, interleukin (IL)-4, and IL-10 polymorphisms in 117 renal cell carcinoma patients, 96 patients with colorectal cancer, and 196 healthy controls to test for an association between polymorphism in these genes and the risk of renal and colon cancer in a Spanish group of patients. In the case-control study, DNA samples from cancer patients and controls were analyzed using a TaqMan single nucleotide polymorphism genotyping assay. The distribution of IL-4 and IL-10 polymorphisms was similar between renal cancer patients and controls. However, a higher incidence of CTLA-4/CT60-AA genotype (p = 0.005; odds ratio (OR)= 2.12 with 95% confidence interval (CI): 1.28-3.50) and CTLA-4/A49G-AA (p = 0.022; OR = 1.76 with 95% CI: 1.11-2.80) genotype was observed in renal cancer patients than in controls. In addition, we observed a positive correlation between the AA genotype in both CTLA-4 polymorphisms and RCC grade, suggesting a role for the CTLA4 gene in tumor development. Therefore, our data suggest the CTLA-4 gene may be a candidate as a renal adenocarcinoma susceptibility gene, but does not play an important role in colon cancer.

HLA-DRB1*1101 allele may be associated with bilateral Méniére's disease in southern European population.

OBJECTIVE: To analyze the associations of HLA-DRB1* and DQB1* Class II alleles in patients with bilateral Méniére's disease (MD). PATIENTS AND METHODS: Eighty patients from two ethnically defined groups with definite bilateral MD, according to the diagnostic scale of the American Academy of Otolaryngology-Head and Neck Surgery, were compared with normal controls from the same origin in a prospective multicenter study. We performed an allele-specific amplification for HLA-DRB1* and DQB1* genes of the major histocompatibility complex. RESULTS: The allele HLA-DRB1*1101 was associated with bilateral MD in the Mediterranean population (odds ratio, 3.65 [95% confidence intervals, 1.5-9.1], corrected p = 0.029); however, this allele was not associated in the group from Galicia (northwest of Spain). No differences were found in the distribution of alleles for the gene HLA-DQB1* between patients and controls. CONCLUSION: The allele HLA-DRB1*1101 and the allelic group HLA-DRB1*11 may determine an increased susceptibility to develop bilateral MD in a southern European population.

Analysis of a GT microsatellite in the promoter of the foxp3/scurfin gene in autoimmune diseases.

The aim of this study was to assess the possible association of the functional (GT)(n) microsatellite polymorphism in the FOXP3 gene with predisposition to several autoimmune diseases such as systemic lupus erythematosus (SLE), rheumatoid arthritis (RA), ulcerative colitis (UC), Crohn's disease, and celiac disease. We analyzed a case-control cohort composed of 231 SLE patients, 293 RA patients, 528 inflammatory bowel disease (354 Crohn's disease patients and 260 UC patients) patients, 103 celiac disease patients, and 274 healthy controls ethnically matched. Genotyping of (GT)(n) microsatellite was performed by polymerase chain reaction (PCR)-based method combined with fluorescent technology. We found no evidence for association of this polymorphism between controls and these autoimmune disease patients. Additionally, no differences in the genotype and allele distribution were found when patients were stratified according to clinical manifestation. The (GT)(n) microsatellite of the FOXP3 gene may not play a relevant role in the susceptibility to SLE, RA, inflammatory bowel disease, and celiac disease in our population.

Evaluation of the association of NKG2C copy number variations with susceptibility to human papillomavirus-induced cervical lesions.

Squamous intraepithelial lesions (SIL) and cervical cancer are primary due to suboptimal host-dependent immune response against human papillomavirus (HPV). Natural killer cells (NK) are innate-immune response components against virus and tumors. We studied whether the null allele of NKG2C NK cell receptor could be associated with low-grade (LSIL) to high-grade SIL (HSIL) transition or likelihood of HPV infection. Eight-hundred and sixty-seven subjects (263 LSIL, 309 HSIL and 295 controls) were genotyped for NKG2C using a novel multiplex PCR protocol. HPV genotype information was obtained from the cases. NKG2C genotype distributions in LSIL were WT/WT: 69.2%, WT/null: 26.2% and null/null: 4.6%; whereas in HSIL were WT/WT: 65.4%, WT/null: 28.5% and null/null: 6.1% and no statistical differences were observed (LSIL vs. HSIL p=0.541; LSIL vs. controls p=0.230; HSIL vs. controls p=0.624) nor when restricting to HPV positive, HR-HPV nor co-infection. This study demonstrates that NKG2Cnull does not seem to constitute a risk factor for HPV-induced cervical lesions.

Lack of association of a functional -94ins/delATTG NFKB1 promoter polymorphism with susceptibility and clinical expression of biopsy-proven giant cell arteritis in northwest Spain.

OBJECTIVE: Giant cell arteritis (GCA) is a vasculitis preferentially involving large and middle-sized arteries in the elderly. The nuclear factor of k-light polypeptide gene enhancer in B cells (NF-kB) is a family of 5 proteins expressed in most cells that function to regulate gene transcription. NFKB1 gene plays a critical role in the coordination of the immune system by regulating the transcription of a broad variety of genes implicated in the immune response. A NFKB1 promoter polymorphism consisting of a common insertion/deletion (-94ins/delATTG) located between 2 putative key promoter regulatory elements and showing functional effects on the transcription of the NFKB1 gene has been described. Since GCA is a polygenic disease, we sought to assess the potential role of the -94ins/delATTG NFKB1 promoter polymorphism in susceptibility to GCA and to determine if this polymorphism is implicated in the clinical expression of this vasculitis. METHODS: Ninety-six patients with biopsy-proven GCA and 204 ethnically matched Caucasian controls from the Lugo region (Northwest Spain) were studied. Genotyping of the -94ins/delATTG NFKB1 promoter polymorphism was performed by fluorescent polymerase chain reaction (PCR). RESULTS: No significant differences in allele or genotype frequencies for this NFKB1 promoter polymorphism were observed between patients with GCA and controls even when patients were stratified according to gender, presence of polymyalgia rheumatica (n = 38), severe ischemic manifestations (n = 49), or other clinical manifestations of GCA. CONCLUSION: Our results do not support a role for -94ins/delATTG NFKB1 promoter polymorphism in susceptibility and clinical expression of GCA in a Northwestern Spanish population.