Host protection against Omicron BA.2.2 sublineages by prior vaccination in spring 2022 COVID-19 outbreak in Shanghai / 医学前沿

The Omicron family of SARS-CoV-2 variants are currently driving the COVID-19 pandemic. Here we analyzed the clinical laboratory test results of 9911 Omicron BA.2.2 sublineages-infected symptomatic patients without earlier infection histories during a SARS-CoV-2 outbreak in Shanghai in spring 2022. Compared to an earlier patient cohort infected by SARS-CoV-2 prototype strains in 2020, BA.2.2 infection led to distinct fluctuations of pathophysiological markers in the peripheral blood. In particular, severe/critical cases of COVID-19 post BA.2.2 infection were associated with less pro-inflammatory macrophage activation and stronger interferon alpha response in the bronchoalveolar microenvironment. Importantly, the abnormal biomarkers were significantly subdued in individuals who had been immunized by 2 or 3 doses of SARS-CoV-2 prototype-inactivated vaccines, supporting the estimation of an overall 96.02% of protection rate against severe/critical disease in the 4854 cases in our BA.2.2 patient cohort with traceable vaccination records. Furthermore, even though age was a critical risk factor of the severity of COVID-19 post BA.2.2 infection, vaccination-elicited protection against severe/critical COVID-19 reached 90.15% in patients aged ≽ 60 years old. Together, our study delineates the pathophysiological features of Omicron BA.2.2 sublineages and demonstrates significant protection conferred by prior prototype-based inactivated vaccines.

Host protection against Omicron BA.2.2 sublineages by prior vaccination in spring 2022 COVID-19 outbreak in Shanghai / 医学前沿

The Omicron family of SARS-CoV-2 variants are currently driving the COVID-19 pandemic. Here we analyzed the clinical laboratory test results of 9911 Omicron BA.2.2 sublineages-infected symptomatic patients without earlier infection histories during a SARS-CoV-2 outbreak in Shanghai in spring 2022. Compared to an earlier patient cohort infected by SARS-CoV-2 prototype strains in 2020, BA.2.2 infection led to distinct fluctuations of pathophysiological markers in the peripheral blood. In particular, severe/critical cases of COVID-19 post BA.2.2 infection were associated with less pro-inflammatory macrophage activation and stronger interferon alpha response in the bronchoalveolar microenvironment. Importantly, the abnormal biomarkers were significantly subdued in individuals who had been immunized by 2 or 3 doses of SARS-CoV-2 prototype-inactivated vaccines, supporting the estimation of an overall 96.02% of protection rate against severe/critical disease in the 4854 cases in our BA.2.2 patient cohort with traceable vaccination records. Furthermore, even though age was a critical risk factor of the severity of COVID-19 post BA.2.2 infection, vaccination-elicited protection against severe/critical COVID-19 reached 90.15% in patients aged ≽ 60 years old. Together, our study delineates the pathophysiological features of Omicron BA.2.2 sublineages and demonstrates significant protection conferred by prior prototype-based inactivated vaccines.

Salmonella entérica serovar Enteritidis biofilm lifestyle induces lower pathogenicity and reduces inflammatory response in a murine model compared to planktonic bacteria / Salmonella entérica serovar Enteritidis en biopelícula induce una menor patogenicidad y respuesta inflamatoria en un modelo murino que su contraparte planctónica

Abstract Salmonella enterica serovar Enteritidis (S. Enteritidis) is the most frequent serovar involved in human salmonellosis. It has been demonstrated that about 80% of infections are related to biofilm formation. There is scant information about the pathogenicity of S. Enteritidis and its relationship to biofilm production. In this regard, this study aimed to investigate the differential host response induced by S. Enteritidis biofilm and planktonic lifestyle. To this purpose, biofilm and planktonic bacteria were inoculated to BALB/c mice and epithelial cell culture. Survival studies revealed that biofilm is less virulent than planktonic cells. Reduced signs of intestinal inflammation and lower bacterial translocation were observed in animals inoculated with Salmonella biofilm compared to the planktonic group. Results showed that Salmonella biofilm was impaired for invasion of non-phagocytic cells and induces a lower inflammatory response in vivo and in vitro compared to that of planktonic bacteria. Taken together, the outcome of Salmonella-host interaction varies depending on the bacterial lifestyle.

Resumen Salmonella entérica serovar Enteritidis (S. Enteritidis) es la serovariedad más frecuentemente aislada en la salmonelosis humana. Se ha demostrado que alrededor del 80% de las infecciones están relacionadas con la formación de biopelículas. Sin embargo, la información disponible acerca de la patogenicidad de S. Enteritidis y su relación con la producción de biopelículas es escasa. Este trabajo tuvo como objetivo investigar la respuesta diferencial del huésped frente a S. Enteritidis en sus 2 estilos de vida: biopelícula y planctónico. Para ello, se inocularon bacterias en estado de biopelícula o planctónico en ratones BALB/c y cultivo de células epiteliales. Los estudios de supervivencia revelaron que Salmonella en biopelícula fue menos virulenta que su contraparte planctónica. Los animales inoculados con biopelículas presentaron una mayor conservación estructural del intestino y una menor translocación bacteriana que el grupo planctónico. Asimismo, Salmonella en biopelícula mostró una capacidad deficiente para invadir células no fagocíticas e indujo una menor respuesta inflamatoria in vivo e in vitro que las bacterias planctónicas. Se concluye que el resultado de la interacción Salmonella-huésped depende del estilo de vida bacteriano.

Genetic, Cellular and Molecular Aspects involved in Apical Periodontitis

Abstract The development, establishment and repair of apical periodontitis (AP) is dependent of several factors, which include host susceptibility, microbial infection, immune response, quality of root canal treatment and organism's ability to repair. The understanding of genetic contributions to the risk of developing AP and presenting persistent AP has been extensively explored in modern Endodontics. Thus, this article aims to provide a review of the literature regarding the biochemical mediators involved in immune response signaling, osteoclastogenesis and bone neoformation, as the genetic components involved in the development and repair of AP. A narrative review of the literature was performed through a PUBMED/MEDLINE search and a hand search of the major AP textbooks. The knowledge regarding the cells, receptors and molecules involved in the host's immune-inflammatory response during the progression of AP added to the knowledge of bone biology allows the identification of factors inherent to the host that can interfere both in the progression and in the repair of these lesions. The main outcomes of studies evaluated in the review that investigated the correlation between genetic polymorphisms and AP in the last five years, demonstrate that genetic factors of the individual are involved in the success of root canal treatment. The discussion of this review gives subsides that may help to glimpse the development of new therapies based on the identification of therapeutic targets and the development of materials and techniques aimed at acting at the molecular level for clinical, radiographic and histological success of root canal treatment.

Resumo O desenvolvimento, estabelecimento e reparo da periodontite apical (PA) depende de vários fatores, que incluem a susceptibilidade do hospedeiro, infecção microbiana, resposta imune, bem como a qualidade do tratamento do canal radicular e a capacidade de reparo do organismo. A compreensão das contribuições genéticas para o risco de desenvolver a PA e apresentar PA persistente tem sido extensivamente explorada na Endodontia moderna. Assim, este manuscrito pretende fornecer uma revisão da literatura em relação aos mediadores bioquímicos envolvidos na sinalização da resposta imune, osteoclastogênese e neoformação óssea, bem como os componentes genéticos envolvidos no desenvolvimento e reparo da PA. Uma revisão narrativa da literatura foi realizada através de uma pesquisa nas bases PUBMED/MEDLINE e uma pesquisa manual nos principais livros sobre a PA. O conhecimento sobre as células, receptores e moléculas envolvidas na resposta imuno-inflamatória do hospedeiro durante a progressão da PA somado ao conhecimento da biologia óssea, especialmente o papel dos osteoblastos, osteócitos e osteoclastos no turnover ósseo, permite a identificação de fatores inerentes ao hospedeiro que podem interferir tanto na progressão como no reparo destas lesões. Os principais resultados dos estudos avaliados na revisão que investigaram a correlação entre polimorfismos genéticos e PA, nos últimos cinco anos, demonstram que os fatores genéticos do indivíduo estão envolvidos no sucesso do tratamento do canal radicular. A discussão desta revisão fornece subsídios que podem ajudar a vislumbrar o desenvolvimento de novas terapias baseadas na identificação de alvos terapêuticos e no desenvolvimento de materiais e técnicas destinadas a atuar a nível molecular para o sucesso clínico, radiográfico e histológico do tratamento endodôntico.

Host response in vivo and the expression of IL-4 in different cross-linked hyaluronic acid composite gels / 国际生物医学工程杂志

Objective To observe the host response and the expression of interleukin-4 (IL-4) in different cross-linked hyaluronic acid composite gels at different time points after the implantation in vivo, and to explore the significance of biocompatibility and macrophage polarization in post-implantation inflammatory response and tissue remodeling. Methods New Zealand white rabbits were respectively injected with crosslinked hyaluronic acid-crosslinked hydroxypropyl methylcellulose gel (sample 1), crosslinked hyaluronic acid-hydroxypropyl methylcellulose gel (sample 2) and commercially available modified sodium hyaluronate gel (control) in subcutaneous tissue at both sides of the spine. Then the rabbits were dissected at 1, 4 and 12 weeks after the implantation. The tissues were fixed with 10％formaldehyde solution, embedded in paraffin and sliced. Hematoxylin-eosin (HE) staining was performed to observe the degree of inflammation and fibrosis. Masson staining was performed to observe the formation of collagen fibers. Immunohistochemical staining was performed to observe the expression of IL-4. Results The results of HE staining showed that the inflammatory reaction in the sample 1 and sample 2 groups was significantly higher than that in the control group 1 and 4 weeks after the implantation. The inflammatory cells aggregated, and the wall of capsule and microcapsule was thick. The sample 1 group was more obvious, and the result was mild stimulation. For all the groups, the results were all non-irritating at 12 weeks after the implantation. The results of Masson staining showed that the collagen fibers in the sample 1 and sample 2 groups were increased compared with the control group, mainly distributed around the implantation site, and a small amount among the gels after 1 and 4 weeks. After 12 weeks, the collagen fibers were further increased, especially among the gels, which were consistent with the control group. The results of immunohistochemical staining showed that, at the same time point, the expression of IL-4 in sample 1 and sample 2 groups was higher than that in the control group, and the expression of IL-4 increased gradually with time. The expression of IL-4 in the control and sample 1 group at 12 weeks after the implantation was higher than that at 1 and 4 weeks respectively, and the differences were statistically significant (all P<0.05). In the sample 1 group, the expression of IL-4 at 12 weeks after the implantation was higher than that at 1 week, and the difference was statistically significant (P<0.05). The expression of IL-4 in the sample 1 group was significantly higher than that in the control group at 4 weeks after the implantation, and the difference was statistically significant (P<0.05). Conclusions The two different cross-linked sodium hyaluronate composite gels have good biocompatibility. The formation of collagen fiber and the expression of IL-4 can gradually increased within 12 weeks after the subcutaneous implantation, which is beneficial to the tissue remodeling.

Integrating host response analysis and VSITA metagenomic detection in cerebrospinal fluid from suspected encephalitis cases / 中华实验和临床病毒学杂志

Objective@#To detect pathogens in clinical cerebrospinal fluid samples from 5 suspected encephalitis cases.@*Methods@#Five cerebrospinal samples were treated with both random and virus sequence independent targeted amplification(VSITA) method , followed by next-generation sequencing. Host trascriptome profiling combined with quantitative PCR were conducted to verify the detected pathogen.@*Results@#Cytomegalovirus(CMV) was detected in 3 cases. Quantitative PCR showed weakly positive result (Ct value: 30.23, 32.83, 34.08). The enhancement result of host infection pathway indicated CMV infection (P=0.213). Sequencing reads analysis showed better result in VSITA (P=0.096).@*Conclusions@#This is the first application of VSITA for cerebrospinal fluid samples. This enrichment method showed great potential while it needs further improvement. Consistency in gene expression detection between VSITA and random method makes it possible for host transcriptome profiling. Analysis result detected increase of CMV infection pathway in 3 positive cases, which further identified CMV infection in the 3 cases.

Genetics in Periodontics.

Periodontal disease does not appear to be a single disease with variations in clinical symptoms but a group of diseases with overlapping symptomatology. The nature of periodontal diseases may be multifactorial. It will be quite important to consider known risk factors for periodontal disease when studying familial clustering or possible genetic mechanisms, because many risk factors for periodontal disease tend to cluster in families through genetic or culture mechanism. It will be important to identify candidate genes that may be the basis for genetic susceptibility to periodontal disease. Genes that may affect immune response to oral bacteria are the most obvious and learning more about traits that predispose to disease, such as tissue response characteristics, may provide additional clues about possible candidate genes. Identification of such genes could enable clinicians better to identify high-risk individuals for targeted prevention and treatment. In the majority of cases, the development of periodontitis in an individual depends probably on the collective presence of a number of environmental risk factors in conjunction with a number of susceptibility factors at a given time point during life. The more susceptibility factors an individual has inherited, the greater the genetic predisposition and the higher the chance for early development of periodontitis. With the increasing knowledge of major and modifying disease genes it is conceivable that a number of genetic tests will be developed. Database was collected using Medline, Cochrane Datbase of systemic reviews, DARE. Database was collected from last 25 yrs to latest keeping in mind all the changes and new evidences which have evolved during this time. Key concept was kept in mind and synonym terms were searched using MeSH headings by running a preliminary search and noting the terms used in the titles and abstracts as well as the subject headings to make the search more sensitive. Search was made more specific by following the inclusion and exclusion criteria for selecting articles like only those relevant articles were searched which offered knowledge and evidence relating to both periodontitis and genetics. Only articles discussing genetics in general were excluded.

Association of interleukin-4 and interleukin-17F polymorphisms in periodontitis in Dravidian ethnicity.

BACKGROUND: Complex network of pro and anti-inflammatory cytokines are known to act in inflamed periodontal tissue. This study explores the distribution of interleukin (IL)-4 (+33 C/T) and IL-17F (7383A/G, 7488A/G) gene polymorphism in chronic and aggressive periodontitis subjects of Dravidian ethnicity. MATERIALS AND METHODS: This case control study consisted of 124 periodontitis individuals comprising of 63 chronic and 61 aggressive periodontitis subjects as cases, and control group consisted of 101 healthy subjects. All subjects were genotyped for IL-4 + 33C/T, IL-17F 7383A/G, 7488A/G by polymerase chain reaction amplification followed by TaqMan assay for IL-4 + 33C/T, restriction enzyme digestion and gel electrophoresis for IL-17F 7383A/G and sequencing for IL-17F 7488A/G. RESULTS: IL-4 + 33C/T was significantly associated with periodontitis (P < 0.05) at both allelic and genotypic level. In subgroup analysis also significant difference (P < 0.05) in allelic distribution between aggressive periodontitis and control group for loci IL-4 + 33C/T was noted. However, there was a lack of association between IL-17F 7383A/G and IL-17F 7488A/G with periodontitis and its sub-groups at both allelic and genotypic levels. CONCLUSIONS: In Malayalam speaking Dravidian population IL-4 + 33C/T loci appears to be an important risk factor for periodontal disease with a leaning towards aggressive periodontitis. The association between IL-17F at 7383A/G and 7488A/G loci with either chronic or an aggressive periodontitis could not be ascertained.

Envolvimento de sinais coestimulatórios na periodontite apical crônica em humanos / Co-stimulatory signals in chronic periapical periodontitis

As lesões periapicais são induzidas por uma infecção crônica da polpa dental. Antígenos microbianos estimulam a resposta imune específica e inespecífica nos tecidos apicais. Como consequência desse processo, diante da incapacidade das defesas do hospedeiro para erradicar a infecção, uma lesão periapical é formada, com o objetivo de restringir a invasão microbiana. O desenvolvimento da periodontite apical crônica depende de uma fina regulação da ativação dos linfócitos. A ativação das células T requer dois sinais, um mediado pelo complexo TCR, após o reconhecimento do antígeno, e o outro mediado pela interação dos receptores coestimulatórios. CD28 é um receptor coestimulatório, enquanto CTLA-4 e PD-1 induzem um sinal inibitório para a ativação de células T. Para compreender o envolvimento de células T na periodontite apical crônica, avaliamos a presença destas células na lesão periapical e os fatores coestimulatórios, citocinas e espécies reativas do oxigênio que estas células estariam produzindo. As amostras analisadas foram de tecido gengival para o grupo controle (n = 20) e lesões periapicais para o grupo com periodontite apical crônica (n = 20). Quanto ao perfil celular das lesões periapicais, os resultados mostraram que linfócitos T (59,3 ± 3,7%) foram as células predominantes, sendo a subpopulação CD4+ (72,7 ± 3,4%) a mais encontrada. A seguir, verificou-se a expressão de moléculas de superfície em células T. Observou-se que a expressão de CD28 (0,5 ± 0,5%) foi significativamente mais baixa em amostras de lesões periapicais que no grupo controle principalmente para linfócito T CD8+. Já CTLA-4 foi identificado em altos níveis para pacientes com periodontite apical tanto para CD3+CD4+ (86,1 ± 2,6%) quanto para CD3+CD8+ (59,8 ± 8,6%). PD-1 (73,5 ± 5,6%) e PD-L1 (59,8 ± 8,6%) apresentaram alta positividade para CD3+CD4+. Esses resultados indicaram um possível envolvimento da via de sinalização de PD-1 e PD-L1 na modulação da resposta de células T de...

Periapical lesions are induced by the chronic infection of dental pulp. Microbial antigens stimulate both non-specific and specific immune response in periapical tissue. As a consequence of these processes and the inability of host defense mechanisms to eradicate infection, chronic periapical lesion are formed, with the aim of restricting microbial invasion. Negative co-stimulatory signals mediated via cell surface molecules such as cytotoxic T-lymphocyte-associated antigen 4 (CTLA-4) and programmed death-1 (PD-1) play a critical role in down- modulation immune responses and maintaining peripheral tolerance. Both CTLA-4 and PD-1 are induced on actived T cell, and these are involved in the immunophatogenesis of periapical lesions. Inhibitory signals mediated via molecules such as programmed-death-1 (PD-1) play a critical role in down-modulating immune responses and maintaining peripheral tolerance. We investigated the involvement of cytokines and PD-1 engagement in mediating the T cell activation in chronic periapical diseases. Gingival samples from healthy individuals (n= 20) and patients with chronic periapical periodontitis (n= 20) were collected and used for the subsequent assays. The leukocytes in the lesion site were evaluated using flow cytometry. The production of cytokines interferon-gamma (IFN-), interleukin (IL)-10, tumor necrosis factor-alpha (TNF-) and transforming growth factor-beta (TGF-) was evaluated by ELISA. We observed a significant increase in the total number of leukocytes from periapical lesions as compared with healthy group. Our results for the composition of infiltrating cell in periapical lesion showed that the predominant cells were lymphocytes T (59,3 ± 3,7%) and contained a higher proportion of CD4+ cells (72,7 ± 3,4%). T cells from patients with periapical lesions expressed significantly higher levels of PD-1 (73,5 ± 5,6%) and PD-L1 (59,8 ± 8,6%). The levels of CTLA-4 were higher in CD3+CD4+ (86,1± 2,6%) and CD3+...

Strain diversity within Mycobacterium avium subspecies paratuberculosis — A review.

Mycobacterium avium subspecies paratuberculosis (MAP), is the etiological agent of Johne’s disease (or paratuberculosis) in animals and has also been linked with Crohn’s disease of human beings. Extreme fastidious nature of the organism (MAP) has hampered studies on diversity within the organism. Studies based on phenotypic properties like growth rate, pigmentation, lipid profile etc., are unable to provide complete information on diversity of MAP organism in nature. However, with the advent of molecular assays (IS900 RFLP, PFGE, IS1311 PCR-REA, SSR typing, VNTR typing etc.) in last 2 decades, progress has been made to differentiate MAP strains. MAP isolates have been classified into various types and subtypes using these molecular tools. Optimization of these typing assays has led to generation of new information about MAP strains, subtypes, their comparative genomics, relative evolution, comparative virulence etc. Knowledge of strain diversity is important for better understanding of molecular and sero-epidemiology, infection and patho-biology, vaccine development and planning control strategies. The present review provides available information on MAP strains, host adaptations, their virulence, comparative genomics, relative genetic evolution and differentiation.

Single-nucleotide Polymorphism (SNP) in β-Defensin 2 in a Japanese Population and an Effect of -1029 SNP on Promoter Activity / Oral Science International

Human β-defensin (hBD) 2 is an epithelial antimicrobial peptide. We studied single-nucleotide polymorphisms in the gene of hBD-2 in a Japanese population, and estimated the effect of a polymorphism in the promoter/enhancer region on the transcriptional activity. By sequencing the hBD-2 gene of 50 unrelated individuals, we detected one SNP in exon 2 and nine SNPs in the promoter/enhancer region. The SNP in the coding region at the +1765 position is synonymous [CCC (Pre)→CCT (Pre)]. One SNP in the promoter region (-1029) is located at the consensus sequence for NF-IL6 binding. By luciferase reporter assay and electrophoretic mobility shift assay, the wild-type (G) of -1029 showed significantly lower transcriptional activity than did the variant-type (A). The SNP at position -1029 may influence the hBD-2 expression and cause genetic variations in susceptibility to infectious diseases.

Single-nucleotide Polymorphism (SNP) in .BETA.-Defensin 2 in a Japanese Population and an Effect of -1029 SNP on Promoter Activity / Oral Science International

Human β-defensin (hBD) 2 is an epithelial antimicrobial peptide. We studied single-nucleotide polymorphisms in the gene of hBD-2 in a Japanese population, and estimated the effect of a polymorphism in the promoter/enhancer region on the transcriptional activity. By sequencing the hBD-2 gene of 50 unrelated individuals, we detected one SNP in exon 2 and nine SNPs in the promoter/enhancer region. The SNP in the coding region at the +1765 position is synonymous [CCC (Pre)→CCT (Pre)]. One SNP in the promoter region (-1029) is located at the consensus sequence for NF-IL6 binding. By luciferase reporter assay and electrophoretic mobility shift assay, the wild-type (G) of -1029 showed significantly lower transcriptional activity than did the variant-type (A). The SNP at position -1029 may influence the hBD-2 expression and cause genetic variations in susceptibility to infectious diseases.