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This work examines cellular immunity against SARS-CoV-2 in patients from Córdoba, Argentina, during two major waves characterized by different circulating viral variants and different social behavior. Using flow cytometry, we evaluated the main lymphocyte populations of peripheral blood from hospitalized patients with moderate and severe COVID-19 disease. Our results show disturbances in the cellular immune compartment, as previously reported in different cohorts worldwide. We observed an increased frequency of B cells and a significant decrease in the frequency of CD3+ T cells in COVID-19 patients compared to healthy donors (HD). We also found a reduction in Tregs, which was more pronounced in severe patients. During the first wave, the frequency of GZMB, CD107a, CD39, and PD-1-expressing conventional CD4+ T (T conv) cells was significantly higher in moderate and severe patients than in HD. During the second wave, only the GZMB+ T conv cells of moderate and severe patients increased significantly. In addition, these patients showed a decreased frequency in IL-2-producing T conv cells. Interestingly, we identified two subsets of circulating CD8+ T cells with low and high CD8 surface expression in both HD and COVID-19 patients. While the percentages of CD8hi and CD8lo T cells within the CD8+ population in HD are similar, a significant increase was observed in CD8lo T cell frequency in COVID-19 patients. CD8lo T cell populations from HD as well as from SARS-CoV-2 infected patients exhibited lower frequencies of the effector cytokine-producing cells, TNF, IL-2, and IFN-γ, than CD8hi T cells. Interestingly, the frequency of CD8lo T cells increased with disease severity, suggesting that this parameter could be a potential marker for disease progression. Indeed, the CD8hi/CD8lo index helped to significantly improve the patient's clinical stratification and disease outcome prediction. Our data support the addition of, at least, a CD8hi/CD8lo index into the panel of biomarkers commonly used in clinical labs, since its determination may be a useful tool with impact on the therapeutic management of the patients.

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Background: COVID-19 severity has been linked to an increased production of inflammatory mediators called "cytokine storm". Available data is mainly restricted to the first international outbreak and reports highly variable results. This study compares demographic and clinical features of patients with COVID-19 from Córdoba, Argentina, during the first two waves of the pandemic and analyzes association between comorbidities and disease outcome with the "cytokine storm", offering added value to the field. Methods: We investigated serum concentration of thirteen soluble mediators, including cytokines and chemokines, in hospitalized patients with moderate and severe COVID-19, without previous rheumatic and autoimmune diseases, from the central region of Argentina during the first and second infection waves. Samples from healthy controls were also assayed. Clinical and biochemical parameters were collected. Results: Comparison between the two first COVID-19 waves in Argentina highlighted that patients recruited during the second wave were younger and showed less concurrent comorbidities than those from the first outbreak. We also recognized particularities in the signatures of systemic cytokines and chemokines in patients from both infection waves. We determined that concurrent pre-existing comorbidities did not have contribution to serum concentration of systemic cytokines and chemokines in COVID-19 patients. We also identified immunological and biochemical parameters associated to inflammation which can be used as prognostic markers. Thus, IL-6 concentration, C reactive protein level and platelet count allowed to discriminate between death and discharge in patients hospitalized with severe COVID-19 only during the first but not the second wave. Conclusions: Our data provide information that deepens our understanding of COVID-19 pathogenesis linking demographic features of a COVID-19 cohort with cytokines and chemokines systemic concentration, presence of comorbidities and different disease outcomes. Altogether, our findings provide information not only at local level by delineating inflammatory/anti-inflammatory response of patients but also at international level addressing the impact of comorbidities and the infection wave in the variability of cytokine and chemokine production upon SARS-CoV-2 infection.

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La inmunodeficiencia común variable(IDCV) es una inmunodeficiencia humoral primaria caracterizada por la disminución de inmunoglobulina G y al menos otra inmunoglobulina, la presencia de infecciones recurrentes y complicaciones no infecciosas como enfermedades autoinmunes, linfoproliferativas o neoplásicas

Summary: Common variable immunodeficiency is a humoral primary immunodeficiency characterized by low LgG levels and of at least another immunoglobulin, recurrent infections, and moninfectious complications, as autoimmune, lymphoproliferative or neoplastic diseases

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BACKGROUND: Surgical techniques as sinus floor augmentation have made it possible to increase the bone volume of the posterior maxilla so that implant placement may be feasible. A large variety of bone grafting materials have been utilized for sinus floor augmentation. A good alternative is allograft. Fresh frozen bone is harvested from live or cadaveric donors and then immediately frozen and stored at -80 °C. To date, studies about the effect of fresh frozen bone are scarce. OBJECTIVE: Evaluation of new bone formation, following maxillary sinus grafting with autograft vs. fresh frozen allograft. MATERIALS AND METHODS: A split-mouth edentulous design including 15 patients was used. Sinus floor augmentation was carried out using either autogenous bone harvested from the ramus area or fresh frozen bone from allogeneic femoral heads. The choice was determined randomly, using a randomized table. The grafted sinus was left to heal for 6 months. Biopsies were harvested from the lateral wall. The biopsies were used for bone histology and histomorphometric analysis. After collection of the biopsy, dental implants were placed. After a healing period of 6 months, the implants were loaded. RESULTS: Implant survival, histology, and histomorphometry of sinuses grafted with autogenous or fresh frozen bone were similar. The new bone formation took place predominantly around and in-between particles. CONCLUSIONS: The findings of the present study support the use of fresh frozen bone allografts for sinus floor augmentation.

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Antecedentes: La alergia al látex es una entidad clínica de baja incidencia que es necesario conocer y reconocer, porque constituye una amenaza a la vida en pacientes susceptibles. Objetivos: Presentación de un caso con revisión de los mecanismos fisiopatológicos, medidas de prevención y tratamiento del shock anafiláctico intraoperatorio. Presentación del caso: Embarazada de término con fuerte antecedente de alergia al látex. Se programa colocar un catéter peridural durante el trabajo de parto pero luego es descartado, por no disponerse de guantes que no sean de látex. Para efectuar la operación cesárea fue necesario retirar previamente todos los elementos del quirófano que contenían látex. La anestesia y cirugía transcurrieron sin inconvenientes.

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Antecedentes: La alergia al látex es una entidad clínica de baja incidencia que es necesario conocer y reconocer, porque constituye una amenaza a la vida en pacientes susceptibles. Objetivos: Presentación de un caso con revisión de los mecanismos fisiopatológicos, medidas de prevención y tratamiento del shock anafiláctico intraoperatorio. Presentación del caso: Embarazada de término con fuerte antecedente de alergia al látex. Se programa colocar un catéter peridural durante el trabajo de parto pero luego es descartado, por no disponerse de guantes que no sean de látex. Para efectuar la operación cesárea fue necesario retirar previamente todos los elementos del quirófano que contenían látex. La anestesia y cirugía transcurrieron sin inconvenientes. (AU)

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BACKGROUND: Allergic Contact Dermatitis (ACD) is regarded as a T-cell-mediated delayed-type hypersensitivity reaction. We studied the kinetics of the expression of CS-1 fibronectin, thymus and activation-regulated chemokine (CCL17/ TARC) and different chemokine receptors (CR) in skin biopsies from individuals suffering from back problems, with the antigen responsible of their contact dermatitis and an irrelevant antigen. METHODS: Samples were taken at 2, 10, and 48 hours for histological and immunohistochemical studies using monoclonal antibodies against human CS-1 fibronectin, CCL17, CD3, CD68, CD49d, CXCR3, CCR5, and CCR3. RESULTS: At positive antigen stimulated sites there was an early expression of CS-1 fibronectin (2 hours), followed by CCL17 and a later accumulation of alplha4/beta1+ (CD49d), CD3+, CD68+, CXCR3+ and CCR5+ mononuclear cells. At 48 hours, approximately 59 % of infiltrating cells were CXCR3+, 42% CCR5+, and only 14 % CCR3+. CONCLUSIONS: These results showed for the first time a very early expression of CS-1 fibronectin which preceded production of CCL17 in blood endothelial cells (BCEs) from patients' skin with ACD. The role of these molecules in recruitment of monocytes and effector T cells in ACD is discussed.

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