Evaluation of the Abdala Vaccine: Antibody and Cellular Response to the RBD Domain of SARS-CoV-2.

Abdala is a recently released RBD protein subunit vaccine against SARS-CoV-2. A few countries, including Mexico, have adopted Abdala as a booster dose in their COVID-19 vaccination schemes. Despite that, most of the Mexican population has received full-scheme vaccination with platforms other than Abdala; little is known regarding Abdala's immunological features, such as its antibody production and T- and B-cell-specific response induction. This work aimed to study antibody production and the adaptive cellular response in the Mexican population that received the Abdala vaccine as a booster. We recruited 25 volunteers and evaluated their RBD-specific antibody production, T- and B-cell-activating profiles, and cytokine production. Our results showed that the Abdala vaccine increases the concentration of RBD IgG-specific antibodies. Regarding the cellular response, after challenging peripheral blood cultures with RBD, the plasmablast (CD19+CD27+CD38High) and transitional B-cell (CD19+CD21+CD38High) percentages increased significantly, while T cells showed an increased activated phenotype (CD3+CD4+CD25+CD69+ and CD3+CD4+CD25+HLA-DR+). Also, IL-2 and IFN-γ increased significantly in the supernatant of the RBD-stimulated cells. Our results suggest that Abdala vaccination, used as a booster, evokes antibody production and the activation of previously generated memory against the SARS-CoV-2 RBD domain.

Exogenous CFH Modulates Levels of Pro-Inflammatory Mediators to Prevent Oxidative Damage of Retinal Pigment Epithelial Cells with the At-Risk CFH Y402H Variant.

Age-related macular degeneration (AMD) is a complex, progressive degenerative retinal disease. Retinal pigment epithelial (RPE) cells play an important role in the immune defense of the eye and their dysfunction leads to the progressive irreversible degeneration of photoreceptors. Genetic factors, chronic inflammation, and oxidative stress have been implicated in AMD pathogenesis. Oxidative stress causes RPE injury, resulting in a chronic inflammatory response and cell death. The Y402H polymorphism in the complement factor H (CFH) protein is an important risk factor for AMD. However, the functional significance of CFH Y402H polymorphism remains unclear. In the present study, we investigated the role of CFH in the pro-inflammatory response using an in vitro model of oxidative stress in the RPE with the at-risk CFH Y402H variant. ARPE-19 cells with the at-risk CFH Y402H variant were highly susceptible to damage caused by oxidative stress, with increased levels of inflammatory mediators and pro-apoptotic factors that lead to cell death. Pretreatment of the ARPE-19 cell cultures with exogenous CFH prior to the induction of oxidative stress prevented damage and cell death. This protective effect may be related to the negative regulation of pro-inflammatory cytokines. CFH contributes to cell homeostasis and is required to modulate the pro-inflammatory cytokine response under oxidative stress in the ARPE-19 cells with the at-risk CFH Y402H variant.

[Validation of a symptom scale for COVID-19 patients in ambulatory care]. / Validación de una escala de síntomas para evaluación ambulatoria en pacientes COVID-19.

Background: A symptom scale can be useful for the standardization of clinical evaluations and follow-up of COVID-19 patients in ambultaroy care. Scale development should be accompanied by an assessment of its reliablility and validity. Objective: To develop and measure the psychometric characteristics of a COVID-19 symptom scale to be answered by either healthcare personnel or adult patients in ambulatory care. Material and methods: The scale was developed by an expert panel using the Delphi method. We evaluated inter-rater reliability, where we defined a good correlation if Spearman's Rho was ≥ 0.8; test-retest, where we defined a good correlation if Spearman's Rho was ≥ 0.7; factor analysis using principal component methodology; and discriminant validity using Mann-Whitney's U test. A p < 0.05 was considered statistically significant. Results: We obtained an 8 symptom scale, each symptom is scored from 0-4, with a total minimum score of 0 and a maximum of 32 points. Inter-rater reliability was 0.995 (n = 31), test-retest showed correlation of 0.88 (n = 22), factor analysis detected 4 factors (n = 40) and discriminant capacity of healthy versus sick adults was significant (p < 0.0001, n = 60). Conclusions: We obtained a reliable and valid Spanish (from Mexico) symptom scale for COVID-19 ambulatory care, answerable by patients and health care staff.

Introducción: una escala de síntomas puede estandarizar la evaluación clínica y el seguimiento de sujetos con COVID-19 durante el cuidado ambulatorio. El desarrollo de una escala nueva debe incluir la determinación de su fiabilidad y validez. Objetivo: desarrollar y analizar las características psicométricas de una escala de síntomas de COVID-19 para ser contestada por personal de salud y por pacientes adultos en el ambiente ambulatorio. Material y métodos: la escala fue desarrollada por un panel de especialistas con el método Delphi. Se evaluó armonía entre jueces, en la cual se definió buena correlación cuando la prueba Rho de Spearman fuese ≥ 0.8; test-retest, en la cual se definió buena correlación cuando la prueba Rho de Spearman fuese ≥ 0.7; análisis factorial por el método de componentes principales, y validez discriminante mediante la prueba U de Mann-Whitney. Una p < 0.05 se consideró estadísticamente significativa. Resultados: se desarrolló una escala que evalúa 8 síntomas que se califican de 0 hasta 4, con calificación mínima total de 0 y máxima de 32 puntos. La armonía entre jueces fue de 0.995 (n = 31), el test-retest mostró una correlación de 0.88 (n = 22), se detectaron 4 factores en el análisis factorial (n = 40) y la capacidad para discriminar entre sanos y enfermos fue significativa (p < 0.0001, n = 60). Conclusiones: se desarrolló una escala de síntomas en español (de México), validada y fiable para la evaluación ambulatoria de pacientes COVID-19, que puede ser contestable por el paciente y por el personal de salud.

Effector-Memory B-Lymphocytes and Follicular Helper T-Lymphocytes as Central Players in the Immune Response in Vaccinated and Nonvaccinated Populations against SARS-CoV-2.

Vaccines have been recognized as having a central role in controlling the COVID-19 pandemic; however, most vaccine development research is focused on IgG-induced antibodies. Here, we analyzed the generation of IgGs related to SARS-CoV-2 and the changes in B- and T-lymphocyte proportions following vaccination against COVID-19. We included samples from 69 volunteers inoculated with the Pfizer-BioNTech (BNT162b2), Astra Zeneca (AZD1222 Covishield), or Sputnik V (Gam-COVID-Vac) vaccines. IgGs related to SARS-CoV-2 increased after the first vaccine dose compared with the nonvaccinated group (Pfizer, p = 0.0001; Astra Zeneca, p < 0.0001; Sputnik V, p = 0.0089). The results of the flow cytometry analysis of B- and T-lymphocytes showed a higher proportion of effector-memory B-lymphocytes in both first and second doses when compared with the nonvaccinated subjects. FcRL4+ cells were increased in second-dose-vaccinated COVID-19(−) and recovered COVID-19(+) participants when compared with the nonvaccinated participants. COVID-19(−) participants showed a lower proportion of follicular helper T-lymphocytes (TFH) in the second dose when compared with the first-vaccine-dose and nonvaccinated subjects. In conclusion, after the first vaccine dose, immunization against SARS-CoV-2 induces IgG production, and this could be mediated by TFH and effector-memory B-lymphocytes. Our data can be used in the design of vaccine schedules to evaluate immuno-bridging from a cellular point of view.

Kinetic Changes in B7 Costimulatory Molecules and IRF4 Expression in Human Dendritic Cells during LPS Exposure.

A key aspect of the inflammatory phenomenon is the involvement of costimulatory molecules expressed by antigen-presenting cells (APCs) and their ability to secrete cytokines to set instructions for an adaptive immune response and to generate tolerance or inflammation. In a novel integrative approach, we aimed to evaluate the kinetic expression of the membrane and soluble B7 costimulatory molecules CD86, ICOS-L, PDL1, PDL2, the transcription factor Interferon Regulatory Factor 4 (IRF4), and the cytokines produced by monocyte-derived dendritic cells (Mo-DCs) after challenging them with different concentrations of stimulation with E. coli lipopolysaccharide (LPS) for different lengths of time. Our results showed that the stimuli concentration and time of exposure to an antigen are key factors in modulating the dynamic expression pattern of membrane and soluble B7 molecules and cytokines.

SARS-CoV-2 Seroprevalence among the Health Care Staff of an Ophthalmological Reference Centre, a Cross Sectional Study.

PURPOSE: During the COVID-19 pandemic, healthcare workers (HCWs) are at a considerable risk of being infected with SARS-CoV-2; among them, HCWs from ophthalmology departments are more prone to develop severe symptoms. In Mexico City, the prevalence of SARS-CoV-2 infection among HCWs is 30%. The present work aims to describe the seroprevalence among HCWs at an Ophthalmological Reference Centre in Mexico City. METHODS: A self-report questionnaire, RT-PCR test and detection of serum IgG/IgM antibodies against SARS-CoV-2 were performed among HCWs at the Institute of Ophthalmology "Conde de Valenciana". RESULTS: A total of 169 HCWs participated in the study. None of the participants declared severe symptoms, and only 15% showed three or more symptoms. The results showed that 32% of the participants were RT-PCR+ (54/169), and 20% (35/169) presented IgG antibodies against SARS-CoV-2. Thirteen percent of the RT-PCR+ subjects were IgG positive, and 7.6% of the RT-PCR- participants were IgG positive. The presence of three or more symptoms correlated with the presence of IgG antibodies, as well as Ct values of < 32 (p < 0,05). CONCLUSION: Most of the HCW cohort showed mild symptoms, and 69% of the RT-PCR+ participants did not show IgG antibodies against SARS-CoV-2. Seroprevalence was significantly associated with the presentation of COVID-19-associated symptoms.

Development and Evaluation of a Set of Spike and Receptor Binding Domain-Based Enzyme-Linked Immunosorbent Assays for SARS-CoV-2 Serological Testing.

The implementation and validation of anti-SARS-CoV-2 IgG serological assays are reported in this paper. S1 and RBD proteins were used to coat ELISA plates, and several secondary antibodies served as reporters. The assays were initially validated with 50 RT-PCR positive COVID-19 sera, which showed high IgG titers of mainly IgG1 isotype, followed by IgG3. Low or no IgG2 and IgG4 titers were detected. Then, the RBD/IgG assay was further validated with 887 serum samples from RT-PCR positive COVID-19 individuals collected at different times, including 7, 14, 21, and 40 days after the onset of symptoms. Most of the sera were IgG positive at day 40, with seroconversion happening after 14-21 days. A third party conducted an additional performance test of the RBD/IgG assay with 406 sera, including 149 RT-PCR positive COVID-19 samples, 229 RT-PCR negative COVID-19 individuals, and 28 sera from individuals with other viral infections not related to SARS-CoV-2. The sensitivity of the assay was 99.33%, with a specificity of 97.82%. All the sera collected from individuals with infectious diseases other than COVID-19 were negative. Given the robustness of this RBD/IgG assay, it received approval from the sanitary authority in Mexico (COFEPRIS) for production and commercialization under the name UDISTEST-V2G®.

Poor Survival in COVID-19 Associated with Lymphopenia and Higher Neutrophile-Lymphocyte Ratio.

BACKGROUND: Immune cell counts in blood in severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) infection may be useful prognostic biomarkers of disease severity, mortality, and response to treatment. OBJECTIVES: To analyze sub-populations of lymphocytes at hospital admission in survivors and deceased from severe pneumonia due to coronavirus disease-2019 (COVID-19). METHODS: We conducted a cross-sectional study of healthcare workers confirmed with SARS-CoV-2 in convalescents (control group) and healthy controls (HC) diagnosed with severe COVID-19. Serum samples were taken at hospital admission and after recovery. Serum samples ≥ 25 days after onset of symptoms were analyzed for lymphocyte subpopulations through flow cytometry. Descriptive statistics, Kruskall-Wallis test, receiver operating characteristic curve, calculation of sensitivity, specificity, predictive values, and Kaplan-Meier analysis were performed. RESULTS: We included 337 patients: 120 HC, 127 convalescents, and 90 severe COVID-19 disease patients (50 survivors, 40 deceased). For T cells, total lymphocytes ≥ 800/µL, CD3+ ≥ 400/µL, CD4+ ≥ 180/µL, CD8+ ≥ 150/µL, B cells CD19+ ≥ 80/µL, and NK ≥ 34/µL subsets were associated with survival in severe COVID-19 disease patients. All subtypes of lymphocytes had higher concentrations in survivors than deceased, but similar between HC and convalescents. Leukocytes ≥ 10.150/µL or neutrophils ≥ 10,000/µL were associated with increased mortality. The neutrophil-to-lymphocyte ratio (NLR) ≥ 8.5 increased the probability of death in severe COVID-19 (odds ratio 11.68). CONCLUSIONS: Total lymphocytes; NLR; and levels of CD3+, CD4+, CD8+, and NK cells are useful as biomarkers of survival or mortality in severe COVID-19 disease and commonly reach normal levels in convalescents.

Increased Expression of TLR4 in Circulating CD4+T Cells in Patients with Allergic Conjunctivitis and In Vitro Attenuation of Th2 Inflammatory Response by Alpha-MSH.

Ocular allergic diseases are frequently seen in ophthalmological clinical practice. Immunological damage is mediated by a local Th2 inflammatory microenvironment, accompanied by changes in circulating cell subsets, with more effector cells and fewer T regulatory cells (Tregs). This study aimed to evaluate the involvement of toll-like receptor 4 (TLR4) and α-melanocyte stimulating hormone (α-MSH) in the immune regulation associated with perennial allergic conjunctivitis (PAC). We performed an Ag-specific stimulation during 72 h of culturing with or without lipopolysaccharide (LPS) or α-MSH in peripheral blood mononuclear cells (PBMC), analyzing the cell subsets and cytokines induced by the stimuli. We also determined α-MSH in tear samples from healthy donors (HD) or PAC patients. Our findings demonstrate an immunological dysregulation characterized by an increased frequency of CD4+TLR4+ in the PBMC of patients with PAC, compared to HD. Most of these CD4+TLR4+ cells were also CD25+, and when α-MSH was added to the culture, the percentage of CD4+CD25+FoxP3+ increased significantly, while the percentage of CD69+ cells and cytokines IL-4 and IL-6 were significantly decreased. In tears, we found an increased concentration of α-MSH in PAC patients, compared with HD. These findings indicate a novel mechanism involved in controlling ocular allergic diseases, in which α-MSH diminishes the concentration of IL-6 and IL-4, restoring the frequency of Tregs and down-regulating CD4 activation. Moreover, we demonstrated the involvement of CD4+TLR4+ cells as an effector cell subset in ocular allergy.

Serum levels of chemokines in adolescents with major depression treated with fluoxetine.

BACKGROUND: Major depressive disorder (MDD) is a global health issue that affects 350 million people of all ages. Although between 2% and 5.6% of affected individuals are adolescents, research on young patients is limited. The inflammatory response contributes to the onset of depression, and in adult MDD patients, symptom severity has been linked to chemokine levels. AIM: To determine the differences in circulatory levels of chemokines in healthy volunteers (HVs) and adolescents with MDD, and assess the changes induced by fluoxetine consume. METHODS: The 22 adolescents with MDD were monitored during the first 8 wk of clinical follow-up and clinical psychiatric evaluation was done using the Hamilton depresión rating scale (HDRS). The serum levels of monocyte chemoattractant protein-1 (MCP-1), macrophage inflammatory protein (MIP)-1α, MIP-1ß, interleukin (IL)-8, interferon gamma-induced protein (IP)-10, and eotaxin were measured in patients and HVs. RESULTS: In all cases, significant differences were detected in circulating chemokine levels between patients before treatment and HVs (P < 0.0001). All chemokines decreased at 4 wk, but only MCP-1 and IL-8 significantly differed (P < 0.05) between 0 wk and 4 wk. In the patients, all chemokines rose to their initial concentrations by 8 wk vs 0 wk, but only IP-10 did so significantly (P < 0.05). All patients experienced a significant decrease in HDRS scores at 4 wk (P < 0.0001) and 8 wk (P < 0.0001) compared with 0 wk. CONCLUSION: Despite the consumption of fluoxetine, patients had significantly higher chemokine levels, even after considering the improvement in HDRS score. The high levels of eotaxin, IP-10, and IL-8 partially explain certain aspects that are affected in MDD such as cognition, memory, and learning.

Activation of IL-10+ B cells: A novel immunomodulatory mechanism for therapeutic bacterial suspensions.

OBJECTIVES: Bacterial components are used to improve immune responses in patients with respiratory infections. Pharmacological formulations of bacterial components include a mixture of bacterial antigens, some of which are complete inactivated bacteria, that is, named bacterial suspensions; while others are fragments of bacteria, which are presented as bacterial lysates. Although bacterial lysates have been broadly used as immune-stimulators, the biological support for the therapeutic effectiveness of bacterial suspension has not yet been studied. Thus, the aim of our study was to investigate the immunological activity induced by bacterial suspension. METHODS: This work was an exploratory translational study. Peripheral blood mononuclear cells were obtained from healthy donors and cultured in time-dose dependent assays with a commercial bacterial suspension. Flow cytometry was used for phenotypic analysis and for determining soluble cytokines in culture supernatants. RESULTS: We observed that bacterial suspension activates B cells in a dose-dependent manner. Peripheral blood mononuclear cells were able to secrete IL-6 and IL-10 after 24 h of bacterial suspension stimulation. TLR2 expression was observed mainly on CD19+ CD38Lo B cells after 72 h of culture; remarkably, most of the TLR2+ CD19+ cells were also IL-10+. CONCLUSION: Our findings suggest that bacterial suspension induces the activation of B cell subsets as well as the secretion of IL-6 and IL-10. Expression of TLR2 on CD19+ cells could act as an activation loop of IL-10+ B regulatory cells. The clinical implications of these findings are discussed at the end of this article.

Low Expression of IL-10 in Circulating Bregs and Inverted IL-10/TNF-α Ratio in Tears of Patients with Perennial Allergic Conjunctivitis: A Preliminary Study.

Allergic conjunctivitis (AC) is one of the most common ophthalmological disorders seen in clinical practice. Growing evidence from recent years suggests that a subset of IL-10-expressing B cells is involved in inflammatory allergic diseases. In this study, we aimed to evaluate the potential involvement of blood Bregs cells in perennial allergic conjunctivitis (PAC), and interleukins (IL)-1ß, IL-6, IL-8, IL-10, and IL-12, and tumor necrosis factor (TNF)-α, were measured in tear samples and compared with healthy controls (HC) using flow cytometry. Non-significant differences in CD19⁺IL-10⁺ cell frequency between PAC patients and healthy controls (HC) were observed. Nevertheless, when we analyzed the mean fluorescence intensity (MFI) of IL-10 on CD19⁺CD38Lo/Med/Hi-gated cells, we observed a significant decrease in MFI in all Bregs subsets in PAC patients. Additionally, tear cytokines showed 2.8 times lower levels of IL-10 than TNF-α in PAC patients when compared to HC. Our findings demonstrate an immunological dysregulation in patients with allergic conjunctivitis, characterized by the low expression of IL-10 in circulating CD19⁺CD38⁺ Bregs subsets and an inverted tear IL-10/TNF-α ratio, promoting a local pro-inflammatory microenvironment. These findings highlight the novel pathologic changes involved in ocular allergic diseases. Understanding systemic and local mechanisms will aid the design of immunomodulating therapeutics at different levels.

Intracellular IL-4, IL-5, and IFN-γ as the main characteristic of CD4+CD30+ T cells after allergen stimulation in patients with vernal keratoconjunctivitis.

BACKGROUND: Vernal keratoconjunctivitis (VKC) is a severe form of allergic conjunctivitis, in which inflammatory infiltrates of the conjunctiva are characterized by CD3+ and CD30+ cells. Until today, the functional involvement of CD30+ T cells in VKC was unclear. Our aim was to evaluate the functional characteristics of CD30+ T cells after allergen stimulation in peripheral blood mononuclear cells obtained from patients with VKC. METHODS: Seventeen consecutive patients at the Institute of Ophthalmology with active forms of VKC were included. RESULTS: After allergen stimulation, we observed the frequency of CD30+ T cells increased compared with non-stimulated cells (p<0.0001). The CD30+ T cells responded to the specific allergen-inducing expression of intracellular interleukin-4 (IL-4), IL-5, and interferon-gamma (IFN-γ) compared with the CD30- T cells (p<0.0001). Increased early secretion of soluble CD30 was observed in the supernatant of the cultured cells from patients with keratoconjunctivitis, compared with healthy controls (p=0.03). Blockage with IL-4 significantly diminished CD30 frequency in the allergen-stimulated cells. CONCLUSIONS: Our results suggest that after allergenic stimulation, CD4+CD30+ cells are the most important source of IL-4, IL-5, and IFN-γ. IL-4 acts as an activation loop that increases CD30 expression on T cells after specific stimulation. These findings suggest that CD4+CD30+ T cells are effector cells and play a significant role in the immune pathogenic response in patients with vernal keratoconjunctivitis.

Expression of IL-8, IL-6 and IL-1ß in tears as a main characteristic of the immune response in human microbial keratitis.

Corneal infections are frequent and potentially vision-threatening diseases, and despite the significance of the immunological response in animal models of microbial keratitis (MK), it remains unclear in humans. The aim of this study was to describe the cytokine profile of tears in patients with MK. Characteristics of ocular lesions such as size of the epithelial defect, stromal infiltration, and hypopyon were analyzed. Immunological evaluation included determination of interleukine (IL)-1ß, IL-6, IL-8, IL-10, IL-12 and tumor necrosis factor (TNF)-α in tear samples obtained from infected eyes of 28 patients with MK and compared with their contralateral non-infected eyes. Additionally, frequency of CD4+, CD8+, CD19+ and CD3-CD56+ cells was also determined in peripheral blood mononuclear cells in patients with MK, and compared with 48 healthy controls. Non-significant differences were observed in the size of the epithelial defect, stromal infiltration, and hypopyon. Nevertheless, we found an immunological profile apparently related to MK etiology. IL-8 > IL-6 in patients with bacterial keratitis; IL-8 > IL-6 > IL-1ß and increased frequency of circulating CD3-CD56+ NK cells in patients with gram-negative keratitis; and IL-8 = IL-6 > IL-1ß in patients with fungal keratitis. Characterization of tear cytokines from patients with MK could aid our understanding of the immune pathophysiological mechanisms underlying corneal damage in humans.

O-glycosylation of NnTreg lymphocytes recognized by the Amaranthus leucocarpus lectin.

O-glycosidically-linked glycans have been involved in development, maturation, homing, and immune regulation in T cells. Previous reports indicate that Amaranthus leucocarpus lectin (ALL), specific for glycans containing galactose-N-acetylgalactosamine and N-acetylgalactosamine, recognizes human naïve CD27(+)CD25(+)CD4(+) T cells. Our aim was to evaluate the phenotype of CD4(+) T cells recognized by ALL in peripheral blood mononuclear cells obtained from healthy volunteers. CD4(+) T cells were isolated by negative selection using magnetic beads-labeled monoclonal antibodies; the expression of T regulatory cell phenotypic markers was assessed on ALL-recognized cells. In addition, IL-4, IL-10, IFN-γ, and TGF-ß intracellular production in ALL (+) cells was also evaluated. The analyses of phenotypic markers and intracellular cytokines were performed through flow cytometry. ALL-recognized CD4(+) T cells were mainly CD45RA(+), CCR7(+) cells. Although 52 ± 10% CD25(+)Foxp3(+) cells were positive to ALL, only 34 ± 4% of ALL (+) cells corresponded to CD25(+)Foxp3(-) cells. Intracellular cytokines in freshly obtained ALL (+)CD4(+) T cells exhibited 8% of IL-4, 15% of IL-10, 2% of IFN-γ, and 15% of TGF-ß, whereas ALL (-)CD4(+) T cells depicted 1% of IL-4, 2% of IL-10, <1% of IFN-γ, and 6% of TGF-ß. Our results show that galactose-N-acetylgalactosamine and N-galactosamine-bearing CD4(+) T cells expressed phenotypic markers of NnTreg cells.

The ocular surface: from physiology to the ocular allergic diseases.

Allergic conjunctivitis (AC) is an inflammation of the conjunctiva secondary to an immune response to exogenous antigens, usually called allergens. In fact, AC is a syndrome that involves the entire ocular surface, including conjunctiva, lids, cornea, and tear film. The signs and symptoms of AC have a meaningful effect on comfort and patient health, and could be influenced by environment, genetics and immune regulation mechanisms, all of which work together in a complex immunological homeostasis. Dysregulation in such immune responses could turn into a variety of ocular allergic diseases (OAD). This review describes some of the current understanding of cellular and molecular pathways involved in different OAD.

La conjuntivitis alérgica es la inflamación de la conjuntiva secundaria a una respuesta inmunitaria contra antígenos exógenos, usualmente llamados alergenos. De hecho, la conjuntivitis alérgica es un síndrome que involucra la totalidad de la superficie ocular, incluyendo la conjuntiva, los párpados, la córnea y la película lagrimal. Los signos y síntomas de la conjuntivitis alérgica tienen un efecto significativo en el bienestar y salud del paciente y pueden ser influidos por el ambiente, la genética y mecanismos de regulación inmunológicos, todos los cuales trabajan en conjunto en una compleja homeostasia inmunológica. La disregulación de estos mecanismos puede desembocar en una gran variedad de enfermedades alérgicas oculares. Esta revisión describe algunos de los conocimientos celulares y moleculares actuales, involucrados en las diferentes enfermedades alérgicas oculares.

[Down regulation of IL-8 and IL-6 in human limbal epithelial cells cultured with human dialyzable leukocyte extracts]. / Células madre epiteliales limbales de IL-8 e IL-6 reguladas hacia la baja en cultivos con dializados de extractos leucocitarios humanos.

INTRODUCTION: Human Limbal Epithelial Cells (hLEC) are stem cells that give rise to corneal epithelium. After corneal damage, hLEC produce large amounts of IL-8 and IL-6, inducing inflammation in cornea and conjunctiva. Despite inflammation is necessary to repair the ocular surface since this process may be potentially harmful and could lead to corneal opacity. Ophthalmic infectious diseases have been treated with human dialyzable leukocyte extracts (hDLE). Clinical observations in hDLE-treated patients, have suggested an apparent control of ocular inflammatory injuries, without changes in the re-epithelialization process. OBJECTIVE: To determine the inflammatory cytokine profile in supernatants (SN) of hLEC cultured with hDLE. METHODS: hLEC were obtained from cadaver donors. hDLE were added to the hLEC cultures, and SN were collected at different times (1h, 3h, 6h, and 24h). IL-1?, IL 6, IL-8, IL-12p70 and TNF-? were measured in SN with cytometric bead arrays. RESULTS: The majority of isolated cells were CK19+/vimentin+/p63+, indicating that cultured-cells were limbal epithelial stem cells. Limbal cells responded to hDLE by diminishing the secretion of IL-8 and IL-6. Secretion of IL-8 and IL-6 was down-regulated significantly at 24h of culture with hDLE. Interestingly, hDLE did not induce secretion of IL-1 ?, TNF-?, and IL-12p70 in hLEC at any evaluated times. CONCLUSIONS: hDLE down-regulates secretion of IL-8 and IL-6 without induction of IL-1 ?, TNF-a, and IL-12p70 in hLEC. Our results provide a basis to understand some clinical effects, related to control ocular inflammation, that have been observed in patients treated with hDLE.

Hypothyroidism in Noninterferon Treated-HCV Infected Individuals Is Associated with Abnormalities in the Regulation of Th17 Cells.

HCV-Ag-specific TH17 cells secrete IL17, a cytokine involved in autoimmune diseases and regulated by IL10 and TGF-b. 5-12% of patients with chronic HCV infection have hypothyroidism. We evaluated the role of these cytokines in this patients by determining serum concentration of TsH, T3, free T4, IL2, IL10, IL12, IL17, TGF-b, anti-TG, TPO, CCP, GBM, and cardiolipin antibodies in 87 chronically noninterferon treated HCV-infected patients. 20 patients (group A) had elevated TsH values (>5 µUI/ml) whereas the remaining 67 (group B) had normal values. The percentage of anti-TPO, TG, GBM, and cardiolipin antibodies in group A patients (33%, 41%, 5% and 5%, resp.) as well as IL17, IL2 and TGF-b concentrations (25 ± 23 pg/ml, 643 ± 572 pg/ml, and 618 ± 221 pg/ml, resp.) were significantly higher than group B. Abnormal Th17 regulation mediated by IL-2 and low TGF-b concentrations is associated with hypothyroidism in chronically-infected HCV patients.

Familial case of Blau syndrome associated with a CARD15/NOD2 mutation.

PURPOSE: Blau syndrome is a rare autosomal dominant disorder characterized by early onset granulomatous arthritis, uveitis, skin rash and camptodactyly. We report a familial case of Blau syndrome associated with a CARD15/NOD2 mutation. METHODS: PCR amplification and automated DNA sequencing of the complete CARD15/NOD2 coding sequence was performed. RESULTS: Molecular analysis in affected subjects disclosed a heterozygous c.1147G>C point mutation in CARD15/NOD2 exon 4, that predicts a p.E383K change at the protein level. CONCLUSIONS: Blau syndrome should be considered in the differential diagnosis of childhood uveitis and the genetic analysis of the CARD15/NOD2 gene is helpful in the diagnosis.

Ocular involvement and blindness secondary to linear IgA dermatosis.

A 43-year-old man with linear immunoglobulin A (IgA) dermatosis associated with gluten intolerance presented with progressive vision loss, pain and photosensitivity in both eyes. His visual acuity was light perception (LP) in both eyes. A physical examination revealed bullous, papular lesions with erythematous borders in periocular tissues, limbs, and thorax. Slit-lamp examination showed conjunctival hyperemia, fibrosis, corneal opacification, and vascularization with epithelial defects. Immunofluorescent skin and corneal surface biopsy studies showed linear IgA deposits. The patient was treated with keratolimbal allogenic transplantation and cryopreserved amniotic membrane in the right eye. Regardless of the treatment he persisted with torpid evolution developing retinal and choroidal detachments. After these events he was started on intravenous immune globulin (IVIG) and showed very slight improvement in ocular surface. These types of blistering diseases are rare in the eye. Even when adequate local treatment is given, systemic treatment is mandatory and ocular prognosis can be unsatisfactory.