High transcript levels of vitamin D receptor are correlated with higher mRNA expression of human beta defensins and IL-10 in mucosa of HIV-1-exposed seronegative individuals

RESUMEN: La vitamina D (VitD) es un inmunomodulador endógena que podría proteger de la infección por VIH-1 la reducción de la activación inmune y la inducción de la expresión de VIH-1 anti-péptidos. Para establecer una correlación entre VitD y resistencia natural a la infección VIH-1, un estudio de casos y controles utilizando sangre y mucosa muestras de 58 VIH-1 expuesto, pero seronegativos (HESN) individuos , 43 VIH-1 seropositivos (SP) y 59 no controles sanos -exposed (HCS) se llevó a cabo. La concentración VitD en el plasma se determinó por ELISA, y de ARNm de unidades relativas (RU) de VDR, IL-10 , TGF-β, TNF-α e IL-1β en las células mononucleares de sangre periférica (PBMCs), oral y genital mucosa se cuantificó por QRT-PCR. mRNA niveles de humana beta -defensin (HBD) -2 y -3 se informó anteriormente y utilizados para correlaciones. Significativamente más altos niveles de VitD se encontraron en plasma, así como mayor mRNA RU de VDR en PBMCs, y en genital mucosa de HESN en comparación con HC. Además, superior mRNA RU de TNF-α, IL-1β y IL-10 , e inferior mRNA RU de TGF-β se encontraron en PBMC de HESNs en comparación con HC. También se observó mayor IL-10 mRNA RU en genital mucosa de HESNs en comparación con HC, y los ARNm de los niveles de TNF-α en oral y genital mucosa de SPs estábamos más alta en comparación con HESNs. Por otra parte, las correlaciones positivas entre VDR y la IL-10 mRNA RU en PBMCs y genital mucosa encontrados de HESNs. Por último, HBD-2 y HBD-3 ARNm RU fueron positivamente correlacionadas con VDR mRNA expresión en forma oral mucosa de HESNs. Estos resultados sugieren que los altos niveles de VitD y su receptor están asociadas con resistencia natural a la infección por VIH-1. Sobre regulación de los anti-inflamatoria IL-10 , y la inducción de anti-VIH-1 defensinas en la mucosa podría ser parte de los mecanismos implicados en esta asociación. Sin embargo, se necesitan más estudios para definir las asociaciones causales.ABSTRACT: Vitamin D (VitD) is an endogenous immunomodulator that could protect from HIV-1 infection reducing immune activation and inducing the expression of anti-HIV-1 peptides. To establish a correlation between VitD and natural resistance to HIV-1 infection, a case-control study using blood and mucosa samples of 58 HIV-1-exposed but seronegative (HESN) individuals, 43 HIV-1 seropositives (SPs) and 59 non-exposed healthy controls (HCs) was carried out. The VitD concentration in plasma was determined by ELISA, and mRNA relative units (RU) of VDR, IL-10, TGF-β, TNF-α and IL-1β in peripheral blood mononuclear cells (PBMCs), oral and genital mucosa was quantified by qRT-PCR. mRNA levels of human beta-defensin (HBD) -2 and -3 were previously reported and used for correlations. Significantly higher levels of VitD were found in plasma as well as higher mRNA RU of VDR in PBMCs, and in genital mucosa from HESN compared to HCs. In addition, higher mRNA RU of TNF-α, IL-1β and IL-10, and lower mRNA RU of TGF-β were found in PBMC from HESNs compared to HCs. We also observed higher IL-10 mRNA RU in genital mucosa of HESNs compared to HCs, and the mRNA levels of TNF-α in oral and genital mucosa of SPs were higher compared to HESNs. Furthermore, positive correlations between VDR and IL-10 mRNA RU in PBMCs and genital mucosa of HESNs were found. Finally, HBD-2 and HBD-3 mRNA RU were positively correlated with VDR mRNA expression in oral mucosa from HESNs. These results suggest that high levels of VitD and its receptor are associated with natural resistance to HIV-1 infection. Up-regulation of the anti-inflammatory IL-10, and the induction of anti-HIV-1 defensins in mucosa might be part of the mechanisms involved in this association. However, further studies are required to define causal associations

Genetic associations of the vitamin D and antiviral pathways with natural resistance to HIV-1 infection are influenced by interpopulation variability

Vitamin D (VitD) may modulate anti-HIV-1 responses modifying the risk to acquire the HIV-1-infection. We performed a nested case-control exploratory study involving 413 individuals; HIV-1-exposed seropositives (cases) and seronegatives (HESN) (controls) from three cohorts: sexually-exposed from Colombia and Italy and parenterally-exposed from Spain. The association and interactions of 139 variants in 9 VitD pathway genes, and in 14 antiviral genes with resistance/susceptibility (R/S) to HIV-1 infection was evaluated. Associations between variants and mRNA levels were also analyzed in the Colombian samples. Variants and haplotypes in genes of VitD and antiviral pathways were associated with R/S, but specific associations were not reproduced in all cohorts. Allelic heterogeneity could explain such inconsistency since the associations found in all cohorts were consistently in the same genes: VDR and RXRA of the VitD pathway genes and in TLR2 and RNASE4. Remarkably, the multi-locus genotypes (interacting variants) observed in genes of VitD and antiviral pathways were present in most HESNs of all cohorts. Finally, HESNs carrying resistance-associated variants had higher levels of VitD in plasma, of VDR mRNA in blood cells, and of ELAFIN and defensins mRNA in the oral mucosa. In conclusion, despite allelic heterogeneity, most likely due to differences in the genetic history of the populations, the associations were locus dependent suggesting that genes of the VitD pathway might act in concert with antiviral genes modulating the resistance phenotype of the HESNs. Although these associations were significant after permutation test, only haplotype results remained statistically significant after Bonferroni test, requiring further replications in larger cohorts and functional analyzes to validate these conclusions.This work was supported by Departamento administrativo de ciencia, tecnología e innovación de Colombia, COLCIENCIAS (grant no. 111549326091); Universidad de Antioquia UdeA, Colombia (sostenibilidad); Universidad Cooperativa de Colombia (code INV1900); Consejería de Salud de la Junta de Andalucía (PI-0335/2009, PI-0118-2013, PI-0481-2012, and AC-0095-2013), Gilead (GLDL13-00145), the Ministerio de Sanidad (EC11-2086, PI021476, and PI10/01232), the Red de Investigación en SIDA (ISCIII-RETIC RD06/006 and RD12/0017), the Fundación Maratón TV3 (020730 and 020732) and the Universidad de Jaén (UJA2013/10/03 and UJA2013/08/12)

THE INTERLEUKIN 21 (IL 21)/ MICRORNA-29 (MIR-29) AXIS IS ASSOCIATED WITH NATURAL RESISTANCE TO HIV-1 INFECTION

BACKGROUND: Interleukin-21 (IL-21) modulates HIV-1 infection through the elicitation of different antiviral mechanisms, including Th17 lineage commitment and induction of microRNA (miR)-29, a miRNA endowed with anti-HIV activity. As miR-29 expression is significantly increased in HIV-1-exposed seronegative individuals (HESNs), we investigated the role of miR-29/IL21 axis in the natural control of HIV-1 infection. METHODS: Analyses were performed in two cohorts of sexually-exposed HESNs, one from Italy and another one from Colombia. Overall the two cohorts included 22 HESNs and 22 HIV-unexposed healthy controls (HCs) whose PBMCs were in vitro infected with an R5-tropic HIV-1Ba-L strain (Italian cohort) and an HIV-1-IIIB X4-tropic HIV-1 (Colombian cohort). Seven days post HIV-1 infection we evaluated: 1) p24 production (ELISA); 2) IL-21+/CD4+ and IL-17+/CD4+ T lymphocytes (FACS); 3) IL-17 concentration in supernatants (ELISA); and 4) IL-6, IL-17, and IL-21 mRNA and miR-29a, b, c expression by CD4+ T lymphocytes and PBMCs as well as perforin and granzymes in PBMCs (qPCR). The same analyses were performed on the 19 HIV-infected partners (HIV+). RESULTS: At baseline IL-6 expression alone was increased in HESNs compared to HCs. Thus, IL-21+/CD4+ and IL-17+/CD4+ T lymphocytes, as well as IL-21 and IL-17 expression and production were significantly augmented in HESNs compared to HCs. Interestingly, IL-21 upregulation correlated with a significantly increased expression of miR-29a, b, c in Italian cohort and with a reduced susceptibility to in vitro HIV-1 infection in HESNs alone. Differences in the expression of perforin and granzymes were observed in the Colombian cohort. CONCLUSIONS: The IL-21/miR-29 axis is upregulated by HIV-1 infection in HESNs suggesting its involvement in the natural resistance to HIV-1 infection in these individuals. Approaches that exogenously increase IL-21 production or prompt pre-existing cellular IL-21 reservoir could confine the magnitude of the initial HIV-1 infection

Multifunctional Activity of the β-Defensin-2 during Respiratory Infections

Human β-defensin-2 is a small cationic peptide that is part of the innate and adaptive immunity. It is expressed mainly in the epithelium and has a broad spectrum of antimicrobial activity against bacteria, fungi and viruses. In addition to its antimicrobial activity, it has other biological functions. The alteration of the expression of β-defensin-2 in the respiratory epithelium has been associated with the pathogenesis of several respiratory diseases such as asthma, pulmonary fibrosis, pneumonia, tuberculosis, rhinitis, etc. The acute respiratory infections caused by viruses are the main cause of morbidity and mortality in the world; there are few studies and it is necessary to study this peptide to understand its role in the viral pathogenesis. In addition, it also becomes relevant in its potential to take advantage of its properties in the development of alternative therapies that allow the prevention or treatment of viral respiratory infections

Distribution of VDR Gene Polymorphisms Bsm-I rs1544410 and Apa-I rs7975232 among HIV/AIDS Patients from West Java

Vitamin D receptor, encoded by VDR gene, mediates vitamin D functions by not only regulating calcium metabolism and homeostasis but also in regulating immune response. Polymorphisms in VDR gene may increase the progression of human immunodeficiency virus (HIV) infection into acquired immunodeficiency syndrome (AIDS). This study aimed to explore the distribution of VDR polymorphisms among HIV sero-positive patients in West Java. A cross-sectional study was performed, recruiting 96 patients infected with HIV and VDR polymorphisms were analyzed. The genotype distributions of Bsm-I among HIV-infected patients were 2.2%, 18.5%, and 79.3% for BB, Bb, and bb, respectively whereas the distributions of Apa-I were 54.4%, 38.9%, and 6.7% for AA, Aa and aa, respectively. The frequency of VDR polymorphisms in Bsm-I among HIV-infected patients in West Java were considered high for b allele (88.6%), and in contrast for A allele in Apa-I that was 73.91%. Further studies involving healthy controls are needed to explore the VDR polymorphisms distribution in general population. Moreover, a cohort study, albeit challenging, is needed to further assess the association between VDR polymorphisms and the progression of HIV infection.Distribusi Polimorfisme gen VDR Bsm-I rs1544410 dan Apa-I rs7975232 pada Pasien HIV/AIDS di Jawa BaratReseptor vitamin D yang dikode oleh gen VDR mempunyai peranan penting terhadap fungsi vitamin D, tidak hanya dalam regulasi metabolisme dan keseimbangan kalsium namun juga berperan dalam meregulasi respon imun. Polimorfisme pada gen VDR ditengarai dapat meningkatkan progresivitas infeksi human immunodeficiency virus (HIV) menjadi acquired immunodeficiency syndrome (AIDS). Penelitian ini bertujuan mengetahui distribusi polimorfisme gen VDR pada pasien HIV di Jawa Barat. Penelitian ini melibatkan 96 pasien HIV dan dilakukan analisis polimorfisme gen VDR. Distribusi genotip Bsm-I pada pasien HIV di Jawa Barat adalah 2,2%, 18,5%, dan 79,3% untuk BB, Bb, dan bb, secara beurutan; sedangkan pada Apa-I adalah 54,4%, 38,9%, dan 6,7% untuk AA, Aa, dan aa. Frekuensi polimorfisme pada Bsm-I pada pasien HIV di Jawa Barat tergolong tinggi pada alel b (88,6%) dan berbanding terbalik pada dan Apa-I dengan alel A yaitu 73,91%. Penelitian lebih lanjut yang melibatkan individu kontrol diperlukan untuk mengetahui distribusi polimorfisme gen VDR pada populasi umum. Selain itu, studi kohort pada pasien HIV/AIDS diperlukan untuk menilai hubungan antara polimorfisme gen VDR terhadap progresivitas infeksi HIV

Ramping Up Antimicrobial Peptides Against Severe Acute Respiratory Syndrome Coronavirus-2

Human-derived antimicrobial peptides (AMPs), such as defensins and cathelicidin LL-37, are members of the innate immune system and play a crucial role in early pulmonary defense against viruses. These AMPs achieve viral inhibition through a variety of mechanisms including, but not limited to, direct binding to virions, binding to and modulating host cell-surface receptors, blocking viral replication, and aggregation of viral particles and indirectly by functioning as chemokines to enhance or curb adaptive immune responses. Given the fact that we are in a pandemic of unprecedented severity and the urgent need for therapeutic options to combat severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2), naturally expressed AMPs and their derivatives have the potential to combat coronavirus disease 2019 (COVID-19) and impede viral infectivity in various ways. Provided the fact that development of effective treatments is an urgent public health priority, AMPs and their derivatives are being explored as potential prophylactic and therapeutic candidates. Additionally, cell-based platforms such as human mesenchymal stem cell (hMSC) therapy are showing success in saving the lives of severely ill patients infected with SARS-CoV-2. This could be partially due to AMPs released from hMSCs that also act as immunological rheostats to modulate the host inflammatory response. This review highlights the utilization of AMPs in strategies that could be implemented as novel therapeutics, either alone or in combination with other platforms, to treat CoV-2–infected individuals

In vitro modelling of the impact of anti-inflammatory drugs on cellular cytotoxicity, activation and inflammation.

Doctoral Degree. University of KwaZulu-Natal, Durban.The relationship between inflammation and HIV has been a major focus of HIV research. In people living with HIV (PLWH), HIV-associated immune activation drives HIV disease progression. While genital inflammation has been significantly associated with increased risk for HIV acquisition and transmission, immune correlates for reduced HIV risk remain less well defined. In HIV-exposed seronegative individuals, the immune quiescent phenotype, characterised by regulated immune activation and inflammation, has been implicated in reducing HIV acquisition risk. Targeted management of inflammation, therefore, is a plausible strategy to mitigate the risk of HIV infection, and to slow HIV disease progression. Therefore, we sought to investigate how anti-inflammatory drugs affect TLR-mediated inflammation and impact HIV infection of CD4+ T cells. This study utilized an in vitro peripheral blood mononuclear cell (PBMC) model. PBMCs were either treated with the anti12 inflammatory drugs ibuprofen (IBF) or betamethasone (BMS) or were left untreated. Thereafter they were either left unstimulated or were stimulated with phytohaemagglutinin (PHA) or Toll-like receptor (TLR) agonists Pam3CSK4 (TLR1/2), LPS (TLR4) or R848 (TLR7/8) before exposure to HIV NL4-3 AD8. To assess inflammation, multiplexed ELISA was used to measure 28 proinflammatory, chemotactic, growth-related, adaptive response-related or regulatory cytokines. Flow cytometry was used to measure activation (CD38, HLA-DR and CCR5) and HIV infection (p24 production) of CD4+ T cells. Despite minimal immune activation, TLR stimulation elicited significant cytokine responses (p<0.05). TLR4 stimulation significantly reduced HIV infection of CD4+ T cells (p<0.01). With the addition of IBF, minimal immunosuppressive effects were observed. In contrast, BMS significantly dampened inflammation (p<0.05) and immune activation (p<0.05) regardless of the stimulation condition. Regardless of global immunosuppression, only with TLR4 stimulation did BMS significantly reduce HIV infection of CD4+ T cells (p=0.02). The finding that TLR4 stimulation reduces rather than increases susceptibility of CD4+ T cells to HIV infection, while BMS only affected HIV infection in the TLR4 condition, strongly suggests that additional factors, and not only inflammation play a powerful, although complex, role in determining HIV infection risk. Together, these data emphasize the importance of understanding signalling pathways induced during inflammation to identify novel targets to mitigate HIV infection

Sequence Variation in GAL1 and GAL2 Genes in Khuzestan Local Chickens

Beta defensins were small, cationic peptides that bind to microbial membranes and disrupt their integrity, thereby exerting antimicrobial effects. These peptides play an important role in innate immunity against microbial pathogens. The aim of the present study was to detect sequence variations, if any, in some beta-defensin gene (GAL1 and GaL2) sequences in Khuzestan local chickens. Blood samples were collected from 20 local chickens and the genomic DNA was isolated using the standard phenol chloroform method. To detect sequence variation, the interested regions of GAL1 and GAL2 were amplified by specific primers with polymerase chain reaction (PCR). Then, the PCR products were sequenced in both directions. Analysis of the GAL1 gene found many sequence variations in the promoter region. GAL2 gene sequencing determined various sequence variations in intronic and exonic regions. These results suggest the existence of numerous genetic variations in these genomic sequences. Further association studies may help the development of a PCR-based genotyping test to select parents with a better immunity

Sequence Variation in GAL1 and GAL2 Genes in Khuzestan Local Chickens

Beta defensins were small, cationic peptides that bind to microbial membranes and disrupt their integrity, thereby exerting antimicrobial effects. These peptides play an important role in innate immunity against microbial pathogens. The aim of the present study was to detect sequence variations, if any, in some beta-defensin gene (GAL1 and GaL2) sequences in Khuzestan local chickens. Blood samples were collected from 20 local chickens and the genomic DNA was isolated using the standard phenol chloroform method. To detect sequence variation, the interested regions of GAL1 and GAL2 were amplified by specific primers with polymerase chain reaction (PCR). Then, the PCR products were sequenced in both directions. Analysis of the GAL1 gene found many sequence variations in the promoter region. GAL2 gene sequencing determined various sequence variations in intronic and exonic regions. These results suggest the existence of numerous genetic variations in these genomic sequences. Further association studies may help the development of a PCR-based genotyping test to select parents with a better immunity

Immunology of the genital tract - a review

The objective of this work was to systematically review and discuss recent studies and articles dealing with the subject of the immunology of female genital tract mucosal tissue. The emphasis hereby lies on the evaluation of studies concerning the basics of female reproductive immunology, research on immunology of the most important genital infections and vaccination strategies, immunologic principles at the fetomaternal interface during normal pregnancy and its complications as well as on immunologic data on infertility and immunocontraception. It is now established that the mucosal immune system is a distinct and separate component of the host`s immune apparatus and differs from the lymphoid tissues in peripheral sites. Furthermore, despite some common features, the female genital tract mucosal system displays some distinct characteristics which outlines its special role. Analysis of the female genital tract indicates that the key cells of the innate and adaptive immune systems are present and functionally responsive to antigens; however, there is a certain degree of compartmentalization within the tract. The identification of TLRs in the fallopian tubes, uterus, cervix, and vagina and the presence of ECs, macrophages, DCs, NK cells, and neutrophils throughout the reproductive tract along with their responsiveness to selected PAMPs indicate that the female reproductive tract has evolved to meet the challenges of STDs, while at the same time supporting an immunologically distinct fetal placental unit. To meet these diverse challenges, innate and adaptive immune system in the female genital tract are precisely regulated not only by a network of cytokines and chemokines, but also by the sex hormones estrogen and progesterone. Understanding the specialty of the genital tract immune system is of critical importance, because STDs are and will be a major worldwide health problem. Despite extensive efforts, only limited success has been achieved in dealing with a growing list of STDs. The role of immune factors in the control of genital viral and bacterial infections appears complex and needs further studying, also with respect to creating vaccines. Despite the recognition that innate immunity as the first line of defense and adaptive immunity, especially Th1 immune responses, play a critical role in preventing infection and in limiting viral replication, factors such as antimicrobials and TLRs that contribute to the mucosal response in the female genital tract have only recently begun to receive attention. Further studies are also needed to elucidate the relationship between mucosal immunity, the hormonal environment, and response to pathogen challenge. More data must be collected on the mechanisms of immune evasion by several pathogens such as HSV, N. gonorrheae or Chlamydia. While considerable information can be obtained from animal experiments, important differences in the physiology of reproduction and the immune sytem result in the need for studies in humans. Further knowledge on female tract immunology will also impact on immunological approaches to contraception, immunological infertility and the immunological aspects of pregnancy. This does not only involve new options for diagnostics but also for treatment of pregnancy complications such as preeclampsia, preterm birth and early pregnancy loss as well as for infertility. Pregnancy involves maternal tolerance of the semiallogenic histoincompatible fetus and is characterized by the enhancement of the innate immune system and suppression of the adaptive immune response, probably with progesterone as the important regulator. In opposite to normal pregnancy, improper immune responses and an unbalanced cytokine network may characterize implantation failures, pregnancy loss and obstetric complications. These are the presence of elevated Th1/Th2 cell ratios, high concentrations of Th1 cytokines, elevated NK cell cytotoxicity and levels, and emergence of various autoantibodies. These immunological approaches needs to be investigated and evaluated further with respect to widening of treatment options by modification of immune responses