Manifestaciones orales y disfunción olfativa y gustativa en el síndrome respiratorio agudo severo por corona virus 2 (VIRUS SARS-COV-2): una revisión sistemáticaA / Oral Manifestations and Olfactory and Gustatory Dysfunction in Severe Acute Respiratory Syndrome Corona Virus 2 (SARSCov-2 Virus) Disease: A Systematic Review

La enfermedad del corona virus 2 del síndrome respiratorio agudo severo (virus SARS-CoV-2) apareció por primera vez en diciembre de 2019 en Wuhan, China, y desde entonces se ha extendido rápidamente por todo el mundo. Desde entonces, el brote de esta grave enfermedad viral se ha convertido en una amenaza global para la humanidad. El diagnóstico precoz y el aislamiento son las medidas más importantes necesarias para prevenir su propagación. La evidencia anecdótica reciente ha sugerido manifestaciones orales con o sin deterioro olfativo y gustativo en asociación con la enfermedad por coronavirus (COVID-19). La enzima convertidora de angiotensina-2 (ECA-2) se expresa en la mucosa oral en grandes cantidades y, por tanto, puede contribuir a las primeras manifestaciones de esta enfermedad viral mortal. Las manifestaciones bucales de la enfermedad por coronavirus pueden presentarse en forma de lesiones ulcerativas irregulares en relación con diferentes partes de la cavidad oral y, en particular, en relación con la mucosa adherida en la región del paladar duro, así como inflamación y posterior atrofia de las diversas papilas de la lengua. La disfunción olfativa y gustativa asociada también puede conducir a una pérdida parcial y / o incluso completa de la capacidad para oler y saborear en las primeras etapas del inicio de la enfermedad. La evidencia también ha sugerido la presencia de ácido nucleico del SARS-CoV-2 en la saliva humana, lo que la convierte en portadora de la enfermedad viral infecciosa y ayuda en su diagnóstico. Hemos buscado sistemáticamente la base de datos médica para el mismo y hemos revisado toda la literatura disponible hasta el 29 de junio de 2020

Severe acute respiratory syndrome corona virus 2 (SARS-CoV-2 virus) disease had first appeared in December 2019 in Wuhan, China and has been spreading quickly throughout the world since then. Since then, the outbreak of this severe viral disease has become a global threat to humanity. An early diagnosis and isolation are the most significant measures required to prevent its spread. Recent anecdotal evidence has suggested oral manifestations with or, without olfactory and gustatory impairment in association with corona virus disease (COVID-19). Angiotensin converting enzyme-2 (ACE-2) is expressed in oral mucosa in large amounts and can, thus, contribute in the early manifestations of this deadly viral disease. The oral manifestations of corona virus disease can occur in the form of irregular ulcerative lesions in relation to different parts of the oral cavity and particularly, in relation to the attached mucosa in the hard palate region as well as inflammation and subsequent, atrophy of the various tongue papilla. The associated olfactory and gustatory dysfunction can, also, lead to partial and/or, even a complete loss of the ability to smell and taste in the early stages of the disease onset. Evidence has, also, suggested the presence of SARS-CoV-2 nucleic acid in human saliva making it the carrier of the infectious viral disease as well as aiding in its diagnosis. We have systemically searched medical database for the same and have reviewed all the literature available up to 29th of June 2020.

L-glutamic acid production in a novel three phase fluidized bed reactor using coimmobilized bio-catalyst.

The production of L-Glutamic acid has been studied using coimmobilized whole cells of pseudomonas reptilivora and micrococcus glutamicus in a three phase fluidized bed bioreactor with selected production medium enriched with glucose. The effect of initial substrate concentration, temperature, pH and aeration rate on the yield of glutamic acid has been investigated. It has been found that the acid production increases exponentially with substrate concentration and mass transfer co-efficient varied linearly with temperature and aeration rate. The optimum temperature and pH are 31 degree Celsius and 7.2 respectively.

Virus-induced immunoinflammatory lesions in the absence of viral antigen recognition.

Herpetic stromal keratitis (HSK) is a CD4+ T cell-controlled immunopathologic lesion in the eye that results from infection with herpes simplex virus (HSV). Target Ags involved in HSK remain undefined. In this study, we determined if HSK could be induced in animals genetically incapable of generating HSV Ag-specific CD4+ T cells. Mice bearing transgenic TCR specific to OVA peptide 323-339 (DO11.10) were crossed to SCID mice whose offspring (Tg-SCID) possessed CD4+ T cells, >98% of which expressed the OVA peptide-specific TCR. HSV infection of Tg-SCID mice was lethal, and mice failed to generate detectable T cell responses even after repeated immunization with a mutant avirulent virus (AN-1). Immunization with AN-1 virus followed by ocular challenge with HSV resulted in ocular inflammation before encephalitis, in contrast to the protection conferred in the control BALB/c and DO11.10 mice. These results indicate that clinical HSK may not require viral Ag recognition by CD4+ T cells and that T cells of irrelevant specificity can be recruited, activated, and driven into effector function in the HSV-infected cornea. This is suggested to represent a bystander activation effect resulting from the presence of proinflammatory mediators resulting from HSV replication.

HSV-1-mediated modulation of cytokine gene expression in a permissive cell line: selective upregulation of IL-6 gene expression.

Pathological effects of herpes simplex virus (HSV) can result due to a combination of direct viropathic effects and immunological reactions to viral antigens. The immunological reactions are orchestrated by a variety of cytokines and chemokines released by the host cells. Therefore, the cytokine gene expression in response to HSV-1 infection in a permissive murine cell line was investigated. The data demonstrate that HSV-1 induced a selective activation of IL-6 gene expression at the mRNA and protein levels, in the permissive cell line. The cell line used was capable of expressing IL-1, IL-7, and IL-10 in addition to IL-6, upon lipopolysaccharide stimulation. UV or heat-inactivated viruses were unable to upregulate IL-6 expression. However, mutant HSV-1 strains lacking fully functional ICP0, ICP4, ICP8, or ICP27 genes, thereby rendering them replication incompetent or impaired in in vitro cell growth (ICP0), enhanced IL-6 expression selectively. Considering the role of IL-6 in inflammation, immune response, and its known association with increased levels of MyD116 and GADD 34 mRNAs (genes involved in the prevention of apoptotic death of cells), the present data may have relevance to HSV-1-mediated diseases as well as to the prevalence of HSV-1 in the host.

Herpes simplex virus type 1-mediated up-regulation of IL-12 (p40) mRNA expression. Implications in immunopathogenesis and protection.

In this report we investigated whether induction of IL-12 occurs in response to herpes simplex virus (HSV) infection of the mouse eye, which may serve to regulate the nature of the subsequent immune response. The data show early induction and continued maintenance of IL-12 (p40) mRNA in the cornea and draining lymph node upon ocular infection with HSV. Using a very sensitive radioimmunoassay technique, IL-12 (p40) protein also was detected in the cornea upon ocular HSV infection. Unfractionated splenocytes and enriched populations of dendritic cells, macrophages, and neutrophils all responded to HSV infection in vitro by up-regulating the expression of IL-12 (p40) mRNA. However, cultured corneal cells failed to generate IL-12 (p40) upon exposure to HSV. The data indicate that inflammatory cells that infiltrate the cornea in response to HSV-1 infection are the main source of IL-12 in the eye. Our results are consistent with the hypothesis that IL-12 induction in the eye acts as a triggering event that biases HSV-specific immunity to a type 1 T cell response, which, in the environment of the eye, culminates in an immunopathologic disease.

Viral replication is required for induction of ocular immunopathology by herpes simplex virus.

Corneal infection of BALB/c mice with herpes simplex virus type 1 results in a chronic inflammatory response in the stroma termed herpetic stromal keratitis (HSK). This disease is considered to be immunopathological and mediated primarily by CD4+ T cells of the type 1 cytokine profile. However, the nature of the antigens, virus or host derived, which drive the inflammatory response remains in doubt. In this study, the relevance of infection with replicating virus for the subsequent development of HSK was evaluated with immunocompetent mice as well as with SCID mice reconstituted with herpes simplex virus-immune CD4+ T cells. In the corneas of immunocompetent mice, infectious virus, viral antigen, and mRNA expression were detectable for only a brief period of time (< or = 7 days postinfection), and all were undetectable by the time clinical lesions were evident (10 to 15 days). Viral replication, however, was necessary for the development of HSK in both models, since infection with UV-inactivated virus or with mutant viruses which were incapable of multiple rounds of replication in vivo failed to induce HSK. The inactivated and mutant viral preparations did, however, stimulate T-cell immune responses in immunocompetent mice. The results are discussed in terms of possible involvement of host antigens exposed in response to transient progeny virion replication in the immune-privileged cornea.

Priming for virus-specific CD8+ but not CD4+ cytotoxic T lymphocytes with synthetic lipopeptide is influenced by acylation units and liposome encapsulation.

Synthetic peptides of the herpes simplex virus glycoprotein B synthesized either as a free form or derivatized with one (PAM1) or three palmitic acids (PAM3Cys) were used to assess the in vivo priming efficacy of high affinity virus-specific CTL induction. The peptide and its derivatives were delivered in vivo with or without liposome encapsulation. Neither the free peptide nor the PAM1 derivative primed for high affinity virus specific CD8+ CTL induction, whether delivered via liposomes or not. On the other hand, the PAM3Cys derivative was able to prime for low levels of high affinity virus specific CD8+ CTL induction in the absence of liposome encapsulation. However, the efficiency of virus-specific CD8+ CTL induction with PAM3Cys derivative was enhanced following encapsulation in the liposomes. In contrast, all forms of the peptides induced both CD4+ T cell proliferative response as well as high affinity virus-specific CD4+ CTL. In addition, the efficiency of the PAM3Cys derivative to prime for CD4+ or CD8+ CTL was found to be influenced by the liposome encapsulation. When delivered via liposomes, the PAM3Cys derivative effectively primed for CD8+ CTL. However, liposomal delivery was not necessary for efficient priming for CD4+ CTL induction. Thus, both the acylation units as well as liposomal delivery appear to influence the in vivo priming of CD4+ and CD8+ T cell responses with synthetic peptides.

T cell cytokine mRNA expression during the course of the immunopathologic ocular disease herpetic stromal keratitis.

Corneal infection with herpes simplex virus in mice induces an inflammatory response in the stroma (herpetic stromal keratitis (HSK)) that appears to represent an immunopathologic reaction in which T cells of the CD4+ subset act as the essential participants. To assess the role of T cell cytokines at different clinical phases of HSK, corneas and draining lymph node (DLN) cells were collected and the levels of mRNA thought to be representative of type 1 and type 2 T cells were quantitated by reverse transcription-PCR. In the corneas collected before the onset of clinical disease, IFN-gamma and IL-4 mRNA were detectable, with levels of IFN-gamma 5- to 15-fold higher than IL-4. During the onset and peak expression of clinical disease, type 1 cytokines IFN-gamma and IL-2 were predominant in the corneas, and IL-4 levels were either very low or undetectable. Neither IL-10 nor IL-5 mRNA was present. After 3 wk postinfection, when some animals with mild disease began to recover, high levels of type 2 cytokine mRNA, particularly IL-10, were present. In addition, only during the recovery phase was IL-10 mRNA present in DLN samples. Levels of transcriptional activity for cytokine mRNA during clinical HSK were higher in corneas than in the corresponding DLN samples. The results indicate that IL-10 may be involved in HSK resolution and that the stimuli for cytokine induction in the cornea may differ from those in the DLN.

Expression of cytokine mRNA in murine splenic dendritic cells and better induction of T cell-derived cytokines by dendritic cells than by macrophages during in vitro costimulation assay using specific antigens.

Among antigen-presenting cells dendritic cells (DC) have the unique ability to generate primary T cell response. The reasons for the superior inductive property of DC still remain obscure. The explanations offered include higher expression of CD80, MHCII, and ICAMI on DC surface which allows effective cluster formation with T cells. It is also possible that additional cellular characteristics of DC, i.e., their ability to release critical mediators involved in the induction of effective immune response, are important. We examined the ability of DC to express IL-1, IL-6, and IL-12 using the highly sensitive reverse transcription-quantitative polymerase chain reaction. Our data show that highly purified (97-99% pure) murine splenic DC were capable of expressing IL-1, IL-6 and IL-12 mRNA upon stimulation with lipopolysaccharide. We also compared the ability of DC and macrophages to induce T cell-derived cytokines IL-2 and IFN-gamma in an in vitro antigen-specific costimulation assay. In naive T cells stimulated with antigen presented via DC or macrophages, the levels of mRNA for IL-2 and IFN-gamma were 2- to 4-fold higher when cells were stimulated with DC. Overall, our data add additional support to the description of DC as superior antigen-presenting cells for the activation of naive T cells.

Limitations and modifications of quantitative polymerase chain reaction. Application to measurement of multiple mRNAs present in small amounts of sample RNA.

Quantification of mRNA by polymerase chain reaction (PCR) is performed by using a competitor DNA standard in the PCR or by employing an internal standard RNA following simultaneous reverse transcription (RT) with the sample RNA. The latter approach is more reliable since it accounts for variations in both the RT and PCR steps. However, we describe in this report that at times the internal standard RNA competes with the target mRNA in the PCR when both are present in disproportionate concentrations in the initial simultaneous RT reaction. To overcome the competition in the PCR, multiple simultaneous RT reactions with the sample RTA and the internal standard RNA are required. Such procedures make the approach time consuming and restrict the use of internal standard RNA for quantification of multiple mRNAs present in small amounts of sample RNA. These limitations are circumvented by the competitor DNA standard approach and mRNA levels can be quantified by calculating the RT efficiency. We illustrate the situations by quantifying the levels of IL-2, IL-4, IL-5, IFN-gamma, and beta-actin mRNAs in mitogen stimulated murine T cells using a multiple mRNA specific internal standard.

Induction of primary, antiviral cytotoxic, and proliferative responses with antigens administered via dendritic cells.

Cytotoxic T lymphocytes (CTL) play an essential role in recovery from viral infections, but induction of CTL responses with nonreplicating antigens is difficult to achieve. Exogenous antigens, such as viral proteins and peptides, normally induce CD4+ T-cell responses unless appropriately delivered to the major histocompatibility complex class I antigen presentation pathway. In vitro studies performed to address this issue revealed a similar scenario, and primary CTL induction with nonreplicating antigens has rarely been reported. This study demonstrated primary antiviral CTL induction in vitro with exogenous antigens delivered in vivo to dendritic cells. This study also evaluated the efficacy of glycoprotein B peptide (free or encapsulated in liposomes), peptide-tripalmitoyl-S-glyceryl cysteinyl conjugate (acylpeptide), and glycoprotein B protein encapsulated in pH-sensitive liposomes as antigen delivery vehicles. Our results show that higher levels of cytotoxicity against herpes simplex virus type 1 resulted from exposure of dendritic cells to peptide-tripalmitoyl-S-glyceryl cysteinyl in liposomes. Macrophages treated in a similar manner were not effective stimulators for primary CTL induction. Our data have relevance to the understanding of mechanisms of antigen processing and presentation and the design of antiviral vaccines.