Longitudinal study of the role of salivary proteins on radiation-related caries onset in head and neck cancer patients using 5000 ppm fluoride dentifrice up to one-year post-intensity modulated radiotherapy.

OBJECTIVES: Longitudinal assessment of the role of specific proteins on radiotherapy caries (RC) onset in head and neck cancer patients(HNC) up to one-year post-IMRT using a 5000ppm fluoride paste daily. MATERIALS AND METHODS: Dental status/salivary protein data were obtained from 40 HNC patients pre-IMRT, six months (T1) and 12 months (T2) post-IMRT (ethical approval/consent). DMFT/salivary parameters were quantified, including flow rate, mucin 5B/7, Immunoglobulin A (IgA), cystatin S and α-amylase. RESULTS: 45% patients had at least one carious lesion at T2, a significant reduction in the number of remaining teeth (65% <21), salivary flow rate (< 50%) and, protein secretion (< 0.05) post-IMRT. T1 IgA concentration/secretion rate was associated with RC (p < 0.05). Finally, IgA and total protein concentration obtained at T1 could provide a predictive pattern (AUC 82.3%) for the patients more predisposed to developing RC at T2. CONCLUSIONS: This study demonstrated the significant association of RC with salivary proteins in HNC patients treated with IMRT, revealing the potential role of salivary proteins in the early diagnosis of RC. CLINICAL RELEVANCE: This research contributes to revealing salivary proteins association with RC, and its role in early diagnosis. Therefore, this could be the first step towards personalized medicine approaches to improve this group quality-of-life.

Crescentic glomerulonephritis due to linear IgA anti-glomerular basement membrane disease: report of a rare case

Anti-glomerular basement membrane (GBM) disease is a rare and severe vasculitis that affects the glomerular and pulmonary capillaries and has an incidence of less than 2 cases per million individuals per year. Anti-GBM disease is mediated by autoantibodies against the α3 chain of type IV collagen. In the majority of cases, the autoantibodies are of the immunoglobulin G (IgG) class, with rare cases being mediated by immunoglobulin M (IgM) or immunoglobulin A (IgA); there are less than 15 IgA-mediated cases reported in the literature worldwide. The classic form of this disease manifests with rapidly progressive glomerulonephritis (RPGN), with or without pulmonary hemorrhage, and the diagnosis consists of identifying high titers of autoantibodies in the serum and/or deposited in the tissues. IgA antibodies are not identified in routine immunoassay tests, and renal biopsy with immunofluorescence is essential for diagnosis. We present a case of RPGN due to anti-GBM disease with linear IgA deposition, whose diagnosis was made exclusively by renal biopsy and with an unfavorable prognosis.

Exercise improves intestinal IgA production by T-dependent cell pathway in adults but not in aged mice.

Introduction: Hypermutated high-affinity immunoglobulin A (IgA), neutralizes toxins and drives the diversification of bacteria communities to maintain intestinal homeostasis although the mechanism underlies the impact of moderate aerobic exercise (MAE) on the IgA-generation via T-dependent (TD) is not fully know. Therefore, the aim of this study was to determine the effect of long-time MAE on the production of IgA through the TD pathway in Peyer´s patches of the small intestine from aged mice. Methods: MAE protocol consisted of twenty 3-month-old (young) BALB/c mice running in an endless band at 0° inclination and a speed of 10 m/h for 5 days a week and resting 2 days on the weekend until reaching 6-month-old (adulthood, n=10) or 24-month-old (aging, n=10). Groups of young, adult, or elderly mice were included as sedentary controls (n=10/per group). At 6 or 24 months old, all were sacrificed, and small intestine samples were dissected to prepare intestinal lavages for IgA quantitation by ELISA and to obtain suspensions from Peyer´s patches (PP) and lamina propria (LP) cells for analysis of T, B, and plasma cell subpopulations by flow cytometry and mRNA analysis expression by RT-qPCR of molecular factors related to differentiation of B cells to IgA+ plasma cells, class switch recombination, and IgA-synthesis. Statistical analysis was computed with two-way ANOVA (factor A=age, factor B=group) and p<0.05 was considered for statistically significant differences. Results: Compared to age-matched sedentary control, in exercised elderly mice, parameters were either increased (IgA concentration, IL-21, IL-10 and RDH mRNA expression), decreased (α-chain mRNA, B cells, mIgA+ B cells, mIgM+ B cells and IL-4 mRNA) or unchanged (PP mIgA+ plasmablasts and LP cyt-IgA+ plasma cells). Regarding the exercised adult mice, they showed an up-modulation of IgA-concentration, mRNA expression IL-21, IL-10, and RDH and cells (PP B and T cells, mIgM+ plasmablasts and LP cyt-IgA+plasma cells). Conclusion: Our findings suggest that MAE restored the IgA production in adult mice via the TD cell pathway but does not in aged mice. Other studies are necessary to know in more detail the impact of long-time MAE on the TD pathway to produce IgA in aging.

IgA-dominant postinfectious glomerulonephritis: a case report.

Introduction: Acute postinfectious glomerulonephritis (APIGN) is an immunological glomerular disease that is an important health issue in developing countries. The incidence remains high in developing countries with a male-to-female ratio of 2:1 and age predominantly above 50 years. In this case study, we present a patient with a history of Staphylococcus epidermidis infection, a past medical history of diabetes mellitus, and histopathological findings of APIGN with Immunoglobulin A (IgA) deposition. Methods: A 58-year-old male presented to the emergency room with a 6-day history of severe low back pain. Three days later, the patient developed fever, chills, abdominal pain in the upper quadrant and a subsequent lower limb cellulitis. Various immunological tests, imaging studies, and kidney biopsy were performed to arrive at a diagnosis. Results: Following the diagnosis and treatment of Cholangitis and Staphylococcus epidermidis, further investigation led to a diagnosis of IgA-dominant APIGN. IgA-dominant APIGN was treated with antibiotics, renin-angiotensin-aldosterone system inhibitors and steroids, and the patient was discharged from the hospital. Conclusion: In developing countries, APIGN is a relatively common presentation of kidney damage due to acute kidney injury and nephritic syndrome. IgA-dominant APIGN is a rare but increasingly recognized morphological variant in which IgA is the sole or dominant immunoglobulin. This unique presentation and multidisciplinary approach for diagnosing and treating IgA-dominant APIGN need to be considered and understood by healthcare professionals to better help these patients. Further investigation is needed to understand the best treatment of this IgA-dominant APIGN presentation and its prognosis.

Select symbionts drive high IgA levels in the mouse intestine.

Immunoglobulin A (IgA) is an important factor in maintaining homeostasis at mucosal surfaces, yet luminal IgA levels vary widely. Total IgA levels are thought to be driven by individual immune responses to specific microbes. Here, we found that the prebiotic, pectin oligosaccharide (pec-oligo), induced high IgA levels in the small intestine in a T cell-dependent manner. Surprisingly, this IgA-high phenotype was retained after cessation of pec-oligo treatment, and microbiome transmission either horizontally or vertically was sufficient to retain high IgA levels in the absence of pec-oligo. Interestingly, the bacterial taxa enriched in the overall pec-oligo bacterial community differed from IgA-coated microbes in this same community. Rather, a group of ethanol-resistant microbes, highly enriched for Lachnospiraceae bacterium A2, drove the IgA-high phenotype. These findings support a model of intestinal adaptive immunity in which a limited number of microbes can promote durable changes in IgA directed to many symbionts.

Chia (Salvia hispanica L.) flour modulates the intestinal microbiota in Wistar rats fed a high-fat and high-fructose diet.

A diet rich in sugar and fat can promote metabolic disorders development, especially in the intestine. Chia flour (Salvia hispanica. L) is a source of dietary fiber, alpha-linolenic fatty acid (ALA), bioactive peptides, and phenolics, promoting health benefits. This study aimed to analyze chia flour's effect on gut microbiota modulation and intestinal health in adult male Wistar rats fed a high-fat and high-fructose (HFHF) diet. Male Wistar rats (n = 10/group) were fed the diets standard (AIN-93M) or HFHF (31% saturated fat and 20% fructose) in the first phase to induce metabolic disorders. In the second phase, the rats were fed AIN-93M, HFHF, or HFHF plus 14.7% chia flour (HFHF + CF) for 10 weeks. The consumption of chia flour increased the ALA (3.24 ± 0.24) intake and significantly improved immunoglobulin A (IgA) levels (1126.00 ± 145.90), goblet cells number (24.57 ± 2.76), crypt thickness (34.37 ± 5.86), crypt depth (215.30 ± 23.19), the longitudinal muscle layer (48.11 ± 5.04), cecum weight (4.39 ± 0.71), Shannon index (p < 0.05), and significantly increased the production of acetic (20.56 ± 4.10) and butyric acids (5.96 ± 1.50), Monoglobus sp., Lachnospiraceae sp., and Prevotellaceae sp. abundance. Furthermore, chia significantly reduced the cecal pH content (7.54 ± 1.17), body mass index (0.62 ± 0.03) and weight (411.00 ± 28.58), and Simpson index (p < 0.05). Therefore, chia intake improved intestinal health parameters and functionality in rats with metabolic disorders, which demonstrates to be an effective strategy for gut microbiota modulation.

IgA nephropathy and kidney transplantation according to the Oxford classification / Nefropatia por IgA e transplante renal segundo a classificação de Oxford

Abstract Introduction: IgA nephropathy (IgAN) is the most common glomerular disease globally, and its susceptibility and the risk for the development of end-stage kidney disease are related to genetic and environmental factors. IgAN recurrence after kidney transplantation is relatively common, impacting graft function and survival. This study evaluated the risk factors and the clinical, laboratory, and histological characteristics of post-transplant IgAN recurrence based on the Oxford classification. Material and methods: Retrospective single-center cohort study including kidney transplant recipients with biopsy-proven pre-transplantation IgAN, with analysis of risk factors and clinical, laboratory, and histological characteristics of the IgAN recurrence cases. Results: 53 patients fulfilled the inclusion criteria and were included in the study. The majority was male, white, eutrophic, with a mean age of 27 ± 9 years at IgAN diagnosis. Systemic arterial hypertension and proteinuria were frequent in the pretransplant period. Four recipients (7.5%) presented IgAN recurrence in a period of 6 to 122 months post-transplant. According to the Oxford classification, they had high scores of mesangial hypercellularity and segmental glomerulosclerosis in the native kidney biopsies and there was mesangial hypercellularity in all analyzed graft biopsies. None of these patients had received induction immunosuppression and all of them presented graft failure in the follow-up. Conclusions: In this series, there was a high prevalence of mesangial hypercellularity and segmental glomerulosclerosis on native kidney biopsies, and mesangial hypercellularity occurred in all IgAN recurrence graft biopsies. Despite the lower incidence of recurrence of IgAN post-transplant compared to previous reports, progression to graft loss was of 100%.

Resumo Introdução: Nefropatia por IgA (NIgA) é a doença glomerular mais comum mundialmente. Sua suscetibilidade e risco para desenvolvimento de doença renal em fase terminal estão relacionados a fatores genéticos e ambientais. A recidiva de NIgA pós-transplante é relativamente comum, impactando na função e sobrevida do enxerto. Este estudo avaliou fatores de risco e características clínicas, laboratoriais e histológicas da recidiva de NIgA pós-transplante, com base na classificação de Oxford. Material e métodos: Estudo de coorte retrospectivo de centro único, incluindo receptores de transplante renal com NIgA pré-transplante comprovada por biópsia, com análise dos fatores de risco e características clínicas, laboratoriais e histológicas dos casos de recidiva de NIgA. Resultados: 53 pacientes preencheram critérios de inclusão e foram incluídos no estudo. A maioria era homem, branco, eutrófico, com idade média de 27 ± 9 anos no diagnóstico de NIgA. Hipertensão arterial sistêmica e proteinúria foram frequentes no período pré-transplante. Quatro receptores (7,5%) apresentaram recidiva de NIgA entre 6-122 meses pós-transplante. Segundo a classificação de Oxford, eles apresentaram altos escores de hipercelularidade mesangial e glomeruloesclerose segmentar nas biópsias de rins nativos. Houve hipercelularidade mesangial em todas as biópsias de enxerto analisadas. Nenhum destes pacientes recebeu imunossupressão de indução. Todos apresentaram falência do enxerto no acompanhamento. Conclusões: Nesta série, houve alta prevalência de hipercelularidade mesangial e glomeruloesclerose segmentar em biópsias de rins nativos, e hipercelularidade mesangial ocorreu em todas as biópsias do enxerto de recidiva da NIgA. Apesar da menor incidência de recidiva de NIgA pós-transplante comparada a relatos anteriores, a progressão para perda do enxerto foi de 100%.

Reference intervals for serum immunoglobulin A levels in Brazilian children aged 1 to 10 years: a population-based study.

OBJECTIVE: To determine reference intervals (RI) for serum immunoglobulin A (IgA) levels in healthy children aged 1 to 1 0 years residing in the central region of Brazil. METHODS: This cross-sectional study was conducted on 1,743 healthy children randomly selected from kindergartens and public schools in Cuiabá, MT, Brazil. The IgA RIs were defined using the statistical methods postulated by the guidelines of the United States Clinical and Laboratory Standards Institute, the nonparametric bootstrap method, and Horn's robust method after the correction of discrepancies by Tukey's, Dixon's, and Horn's methods, respectively. The results were defined based on the values contained between the 2.5th and 97.5th percentiles and their respective 95% confidence intervals. RESULTS: Partition by sex was not necessary to determine the IgA RI of the studied children. Homogeneous subgroups were identified among children aged 1-<2, 2-<5, and 5-<11 years, whose IgA-specific RIs were determined. CONCLUSION: The serum IgA RIs were established for three groups of Brazilian children aged 1-11 years, which differed from those currently applied in Brazilian pediatric practice and from those defined by international studies. This definition will help Brazilian pediatricians formulate an accurate diagnosis and facilitate decision-making.

IgA antibody dynamics in healthcare workers after CoronaVac® vaccination and heterologous Comirnaty® booster dose.

BACKGROUND: This study is aimed at calculating the IgA antibody dynamic range in healthcare workers (HCWs) after immunization with CoronaVac® and Comirnaty® booster dose. METHODS: A total of 118 HCW serum samples from Southern Brazil were collected the day before the first vaccine dose (day 0) and + 20, + 40, + 110, + 200 days following the vaccine's first dose, and + 15 days after a Comirnaty® booster dose. Immunoglobulin A (IgA) was quantified using immunoassays for anti-S1 (spike) protein antibodies (Euroimmun, Lübeck, Germany). RESULTS: Seroconversion for the S1 protein occurred in 75 (63.56%) and 115 (97.47%) HCWs by day + 40 and day + 15 after the booster dose, respectively. There was an absence of IgA antibodies after the booster dose in two (1.69%) HCWs undergoing biannual rituximab administration and one (0.85%) HCW for no apparent reason. CONCLUSION: Complete vaccination showed a significant IgA antibody production response, and the booster dose considerably increased this response.

Schõnlein-Henoch purpura in adults: Report of four cases

Schoenlein-Henoch purpura is a systemic small vessel vasculitis mediated by IgA-1 deposition in organs such as the skin, kidney, and gastrointestinal tract; it has been mainly described in children where it has a favourable prognosis. Although much rarer in adulthood it is associated with an increased risk of severe kidney involvement, gastrointestinal com-plications, and prolonged hospital stay. The therapeutic options are wide and vary according to the degree of involvement of the patient and the organ mainly affected.

La púrpura de Schönlein-Henoch es una vasculitis sistêmica de pequeno vaso mediada por depósito de IgA en órganos como la piel, el riñón y el tracto gastrointestinal. Se ha descrito principalmente en niños, grupo de población en el que tiene un pronóstico favorable. Si bien en la edad adulta es mucho menos frecuente, se asocia con un mayor riesgo de compromiso renal severo, complicaciones gastrointestinales y estancia hospitalaria prolongada. Las opciones terapêuticas son amplias y varían según el grado de compromiso del paciente y el órgano más afectado.

Outcomes of nicotinic modulation on markers of intestinal IgA antibody response.

Acetylcholine (ACh), as a ligand of nicotinic acetylcholine receptors (nAChRs), plays a key role in the cholinergic anti-inflammatory pathway; however, its role in the immunoglobulin A (IgA) response remains unknown. Therefore, the present study aimed to investigate the role of ACh in the intestinal biomarkers involved in IgA synthesis and the polymeric immunoglobulin receptor (pIgR) involved in IgA transcytosis. Groups of mice were administered GTS-21 (an α7nAChR agonist) or mecamylamine (a non-selective nAChR antagonist) intraperitoneally for 7 days. Intestinal fluids were used for antibody concentration assessment by ELISA, cell suspensions from Peyer's patches and the lamina propria were obtained for flow cytometric analysis of plasma cells, and CD4+ T-cells expressing intracellular transforming growth factor (TGF)-ß and IgA-producing interleukin (IL)-4, -5, -6 and -10, and isolated epithelial cells to determine the levels of pIgR mRNA using reverse transcription-quantitative PCR. Regarding to the untreated control group, the concentration of IgA was reduced in the mecamylamine group and unaltered in the GTS-21 group while IgM levels exhibited no differences; the percentage of IgA+ plasma cells from Peyer's patches and the lamina propria, and the percentage of TGF-ß+/CD4+ T-cells from Peyer's patches were greater in the GTS-21-group. In both treatment groups, the percentages of IgM+ plasma cells and IL-6+/IL-10+ CD4+ T cells were greater in both compartments; pIgR mRNA expression levels decreased in epithelial cells. The percentage of IL-4 CD4+ T-cells were greater in Peyer's patches and lower in the lamina propria in the mecamylamine group, and the percentage of IL-5 CD4+ T-cells in the lamina propria were decreased in both treatment groups. These findings require further examination to address the impact of cholinergic modulation on IgA-transcytosis via pIgR. The present study may be an experimental reference for clinical trials that address the role of nicotinic system in intestinal dysfunctions as postoperative ileus.

Reference intervals for serum immunoglobulin A levels in Brazilian children aged 1 to 10 years: a population-based study

Abstract Objective: To determine reference intervals (Rl) for serum immunoglobulin A (IgA) levels in healthy children aged 1 to 1 0 years residing in the central region of Brazil. Methods: This cross-sectional study was conducted on 1,743 healthy children randomly selected from kindergartens and public schools in Cuiabá, MT, Brazil. The IgA RIs were defined using the statistical methods postulated by the guidelines of the United States Clinical and Laboratory Standards Institute, the nonparametric bootstrap method, and Horn's robust method after the correction of discrepancies by Tukey's, Dixon's, and Horn's methods, respectively. The results were defined based on the values contained between the 2.5th and 97.5th percentiles and their respective 95% confidence intervals. Results: Partition by sex was not necessary to determine the IgA Rl of the studied children. Homogeneous subgroups were identified among children aged 1-<2, 2-<5, and 5-<11 years, whose IgA-specific RIs were determined. Conclusion: The serum IgA RIs were established for three groups of Brazilian children aged 1-11 years, which differed from those currently applied in Brazilian pediatric practice and from those defined by international studies. This definition will help Brazilian pediatricians formulate an accurate diagnosis and facilitate decision-making.

Dermatosis ampollar por IgA lineal inducida por Vancomicina: reporte de un caso / Vancomycin-induced linear igabollous dermatosis: a case report

RESUMEN La dermatosis ampollar por IgA lineal del adulto (DLA) es una enfermedad autoinmune adquirida infrecuente, caracterizada por el depósito lineal de anticuerpos IgA en la membrana basal. La mayoría de los casos reportados son de causa idiopática, pero esta entidad también se ha visto asociada a ciertos fármacos, siendo la vancomicina el más frecuente. Se presenta un caso de DLA asociada a vancomicina, con extensa afectación cutánea y compromiso mucoso, tratado con dapsona y corticoides sistémicos con buena respuesta.

ABSTRACT Adult linear IgA bollous dermatosis (LABD) is a rare acquired autoimmune disease characterized by linear deposition of IgA antibodies on the basement membrane. Most of the reported cases are of idiopathic cause, but this entity has also been associated with certain drugs, vancomycin being the most frequent. We present a case of LABD associated with vancomycine, with extensive skin and mucosal involvement, treated with dapsone and systemic corticosteroids with a good response.

Case report: effect of umbilical cord mesenchymal stem cells on immunoglobulin A nephropathy after acute renal failure.

Immunoglobulin A nephropathy is an inflammatory, autoimmune condition that may lead to renal impairment in its most aggressive forms. In this case report, a 50-year-old male with acute renal failure was diagnosed with IgA nephropathy, having elevated creatinine levels (3.0 mg/dL) and hypertension. He received intravenous infusions of a total of 120 million umbilical cord-derived mesenchymal stem cells (UC-MSCs) and was followed-up for 6 months. No adverse events were reported during or after administration or any of the follow-up visits. Creatinine levels decreased to and remained normal (1.0 mg/dL) in the 6 months following treatment. Anti-hypertensive medications were no longer needed. UC-MSC administration was safe, well-tolerated, and beneficial for this patient with IgA nephropathy.

The role of IgA in gastrointestinal helminthiasis: A systematic review.

Immunoglobulin-A (IgA) is an important mediator of immunity and has been associated with protection against several pathogens, although its role in gastrointestinal infections remains unclear. Then, the aim of this systematic review was to synthesize qualitative evidence in respect of IgA as mediator of protective immunity against gastrointestinal helminths. Following recommended guidelines, we searched for articles published between January 1990 and October 2019 that evaluated IgA levels and their association with gastrointestinal helminth infections. Twenty-five articles were included after screening 1,546 titles and abstracts, as well as reading in full 52 selected articles. Consistent associations between higher IgA levels and lower parasitological parameters were only found in mice, rats, and sheep. However, the role of IgA in other host species remains uncertain, making it difficult to create a consensus. Therefore, it is too soon to claim that IgA is an effective protective factor against gastrointestinal helminths, and further studies are still needed.

Colostrum Use and the Immune System of Premature Newborns: A Systematic Review and Meta-Analysis.

BACKGROUND: Human colostrum has been used in a number of investigations when preterm human infants cannot, for any reason, breastfeed directly from their mothers. One of the growing fields in these investigations is colostrum therapy, which consists of exposing the oropharyngeal mucosa of these preterm newborns to small amounts of raw colostrum. RESEARCH AIM: To critically review the scientific evidence about colostrum therapy in premature infants and to explore its influences on the immune system. METHODS: This systematic review was performed according to the preferred reporting items for systematic reviews and meta-analyses (PRISMA statement). The following databases were searched for potentially eligible studies up to March 10, 2021: Medline, Scopus, Web of Science, Cochrane Library, Embase. Two reviewers independently screened all titles, abstracts, and full texts for eligibility. RESULTS: A total of 12 studies with 996 participants were included. A significant difference in lactoferrin levels in the urine was found (SMD 0.70; 95% CI [0.03,1.36]; p = .04; I² = 65% two studies, 112 participants, very low-quality evidence). CONCLUSION: Colostrum seems to result in increasing lactoferrin levels in the urine of premature newborns after 1 week of intervention. CLINICAL TRIAL REGISTRATION: The study was registered at PROSPERO with the number CRD42017073624, submitted on August 9, 2017.

Algoritmo para el diagnóstico y tratamiento de la hipoplasia del timo pediátrica, asociada o no a inmunodeficiencia / Algorithm for diagnosis and treatment of thymus hypoplasia in childhood, associated or not with immune deficiency

Hace aproximadamente 20 años un grupo de médicos investigadores de Cuba reportaron el empleo de las mediciones del timo por ultrasonografía, como un arma valedera en la evaluación inmunológica de los niños menores de 7 años con cuadros de infecciones frecuentes, fundamentalmente respiratorias. El rango de normalidad propuesto del área de la silueta tímica, es entre 1010,6 - 1425,4 mm2, o sea, 1 218 ± 207,4 mm2. Por debajo y por encima de estos valores se hablaría de hipoplasia e hiperplasia, respectivamente. Se considera hipoplasia grave cuando el área tímica es menor de 500 mm2; moderada cuando se encuentra entre 500 y 799 mm2 y leve cuando se halla entre 800 y 999 mm2. Se propone un algoritmo de diagnóstico y tratamiento que engloba la experiencia clínica de 12 años de trabajo en inmunología clínica pediátrica en el Instituto de Hematología e Inmunología. Este puede constituir una herramienta útil en las manos de los inmunólogos clínicos pediátricos que adecuarían el tratamiento idóneo para llevar el órgano a su tamaño estándar con la consecuente disminución de los procesos infecciosos y la elevación de los niveles de inmunoglobulina A en los pacientes(AU)

About 20 years ago, a group of Cuban medical researchers reported to the literature the use of measurements of the thymus by ultrasonography, as a valid weapon in the immunological evaluation of children under 7 years of age with frequent infections, mainly respiratory. The range of normality proposed for the area of the thymic silhouette is between 1010.6 - 1425.4 mm2, that is, 1 218 ± 207.4 mm2. Below and above these values, we would speak of hypoplasia and hyperplasia, respectively. Severe hypoplasia is considered when the thymic area is less than 500 mm2; moderate when it is between 500 and 799 mm2 and mild when it is between 800 and 999 mm2. A diagnosis and treatment algorithm is proposed that encompasses the clinical experience of 12 years of work in pediatric clinical immunology at the Institute of Hematology and Immunology. It can be a useful tool in the hands of pediatric clinical immunologists who would adapt the ideal treatment to bring the organ to its standard size with the consequent decrease in infectious processes and the elevation of immunoglobulin A levels in patients(AU)

IgA Deficiency Is Not Systematically Ruled Out in Patients Undergoing Celiac Disease Testing.

BACKGROUND: Guidelines for celiac disease (CD) testing recommend total serum IgA determination alongside anti-transglutaminase IgA antibodies. It is not well known if lack of serum IgA determination is a common finding in clinical practice. AIM: To determine the prevalence of lack of serum IgA determination among patients screened for celiac disease. MATERIALS AND METHODS: We identified all subjects who underwent serum anti-transglutaminase IgA and/or other CD-related antibodies determination at a single teaching hospital in Buenos Aires from October 2019 to February 2020. Medical records were reviewed to select adult patients who were tested for celiac disease. The primary outcome was the proportion of patients with inadequate testing for celiac disease due to lack of serum IgA determination. We retrieved the following variables from each patient's record: age, gender, body mass index, symptoms present at screening, first-grade family history of CD, history of type-1 diabetes mellitus, autoimmune hypothyroidism, Down's syndrome. RESULTS: Overall, 1122 patients were included for analysis. Lack of serum IgA determination prevalence was 20.49%. Among patients who did have serum IgA determination, the prevalence of IgA deficiency was 5.16%. The following variables were independently associated with a significantly increased odds of serum IgA determination: diarrhea [OR 1.55 (1.01-2.34)] and abdominal pain [OR 2.28 (1.44-3.63)]; higher body mass index [OR 0.91 (0.85-0.98)], osteoporosis [OR 0.49 (0.28-0.89)], hypothyroidism [OR 0.18 (0.07-0.45)], arthralgia/arthritis [OR 0.47 (0.27-0.85)], or testing by endocrinologist [OR 0.46 (0.23-0.91)] and gynecologist [OR 0.14 (0.06-0.31)] were inversely associated. CONCLUSION: IgA deficiency is not systematically ruled out in a relatively high proportion of patients undergoing serological screening of celiac disease.

[The involvement of vitamin A in the production of secretory IgA in the respiratory epithelium for potential protection against SARS-CoV-2 infection]. / Participación de la vitamina A en la producción de IgA secretora en el epitelio del tracto respiratorio para la potencial protección de infección por SARS-CoV-2.

SARS-CoV-2 continues to infect thousands of people around the world. It has been established that the main transmission mechanism of this virus is via airborne route, which is why it initially infects the respiratory tract. Currently, the effectiveness of medications used against COVID-19 is limited, and although immunization programs have been initiated, there is international inequality in the distribution of vaccines. Accordingly, the search for adjuvant therapies continues to be an alternative for research. Supplementation with vitamin A has been associated to the decrease of mortality from infection; this effect could be mediated by retinoic acid (RA), which is the active metabolite of vitamin A that exerts immunomodulatory functions. According to preclinical studies, RA favors the production of secretory immunoglobulin A (IgA) in the respiratory tract. In addition to this, the retinol-binding protein has been correlated with the concentration of IgA and neutralizing antibodies in patients with influenza. Therefore, this review aims to address the involvement of vitamin A in the production of secretory IgA in the respiratory epithelium in order to highlight its potential protection against SARS-CoV-2 infection.

El SARS-CoV-2 continúa infectando a miles de personas a nivel mundial. Se ha establecido que el principal mecanismo de transmisión del SARS-CoV-2 es por vía aérea, por lo que infecta inicialmente el tracto respiratorio. Actualmente, la eficacia de los fármacos utilizados contra COVID-19 es limitada y a pesar de que los programas de inmunización han iniciado, existe una desigualdad internacional en la distribución de vacunas. En este sentido, la búsqueda de terapias coadyuvantes continúa siendo una alternativa para su investigación. La suplementación con vitamina A se ha asociado con la reducción de mortalidad por infecciones; este efecto podría ser mediado por el ácido retinoico (AR), un metabolito activo de esta vitamina, que ejerce funciones inmunomoduladoras. De acuerdo con estudios preclínicos, el AR favorece la producción de inmunoglobulina A (IgA) secretora en el tracto respiratorio. Aunado a esto, la proteína de unión a retinol se ha correlacionado con la concentración de IgA y anticuerpos neutralizantes en pacientes con influenza. Por lo tanto, la presente revisión tiene como objetivo abordar la participación de la vitamina A en la producción de la inmunoglobulina A secretora en el epitelio del tracto respiratorio para resaltar su potencial función protectora contra la infección por SARS-CoV-2.

Acute and Chronic Effects of Interval Training on the Immune System: A Systematic Review with Meta-Analysis.

PURPOSE: To summarize the evidence regarding the acute and chronic effects of interval training (IT) in the immune system through a systematic review with meta-analysis. DESIGN: Systematic review with meta-analysis. DATA SOURCE: English, Portuguese and Spanish languages search of the electronic databases Pubmed/Medline, Scopus, and SciELO. Eligibility criteria: Studies such as clinical trials, randomized cross-over trials and randomized clinical trials, investigating the acute and chronic effects of IT on the immune outcomes in humans. RESULTS: Of the 175 studies retrieved, 35 were included in the qualitative analysis and 18 in a meta-analysis. Within-group analysis detected significant acute decrease after IT on immunoglobulin A (IgA) secretory rate (n = 115; MD = -15.46 µg·min-1; 95%CI, -28.3 to 2.66; p = 0.02), total leucocyte count increase (n = 137; MD = 2.58 × 103 µL-1; 95%CI, 1.79 to 3.38; p < 0.001), increase in lymphocyte count immediately after exercise (n = 125; MD = 1.3 × 103 µL-1; 95%CI, 0.86 to 1.75; p < 0.001), and decrease during recovery (30 to 180 min post-exercise) (n = 125; MD = -0.36 × 103 µL-1;-0.57 to -0.15; p < 0.001). No effect was detected on absolute IgA (n = 127; MD = 47.5 µg·mL-1; 95%CI, -10.6 to 105.6; p = 0.11). Overall, IT might acutely reduce leucocyte function. Regarding chronic effects IT improved immune function without change leucocyte count. CONCLUSION: IT might provide a transient disturbance on the immune system, followed by reduced immune function. However, regular IT performance induces favorable adaptations on immune function.