Monocytes subpopulations pattern in the acute respiratory syndrome coronavirus 2 virus infection and after long COVID-19

INTRODUTION AND OBJECTIVE

The present study sought to characterize the pattern of monocyte subpopulations in patients during the course of the infections caused by SARS-CoV-2 virus or who presented long COVID-19 syndrome compared to monocytes from patients with zika virus (Zika) or chikungunya virus (CHIKV).

CASUISTRY

Study with 89 peripheral blood samples from patients, who underwent hemogram and serology (IgG and IgM) for detection of Zika (Control Group 1, n = 18) or CHIKV (Control Group 2, n = 9), and from patients who underwent hemogram and reverse transcription polymerase chain reaction for detection of SARS-CoV-2 at the acute phase of the disease (Group 3, n = 19); and of patients who presented long COVID-19 syndrome (Group 4, n = 43). The monocyte and subpopulations counts were performed by flow cytometry.

RESULTS

No significant difference was observed in the total number of monocytes between the groups. The classical (CD14++CD16-) and intermediate (CD14+CD16+) monocytes counts were increased in patients with acute infection or with long COVID-19 syndrome. The monocytes subpopulations counts were lower in patients with infection Zika or CHIKV.

CONCLUSION

Increase in the monocyte subpopulations in patients with acute infection or with long COVID-19 syndrome may be an important finding of differentiated from the infection Zika or CHIKV.

Análise dos Critérios Imunofenotípicos por Citometria de Fluxo para Definição das Doenças Linfoproliferativas Crônicas de Células B

Introdução: A citometria de fluxo é uma metodologia importante para o diagnóstico das doenças linfoproliferativas crônicas de células B (DLPCB), contudo, por vezes, o citometrista não encontra subsídios suficientes para a definição exata da entidade patológica envolvida. Objetivo: Analisar os laudos emitidos a pacientes com doenças linfoproliferativas crônicas (DLPC) atendidos em um laboratório particular de Belém-PA, segundo os critérios de classificação estabelecidos pelos estudos de Matutes et al. e Craig e Foon. Método: Estudo retrospectivo com laudos de pacientes que realizaram imunofenotipagem por citometria de fluxo para diagnóstico de DLPCB no período entre setembro de 2015 a dezembro de 2019. Resultados: Depois de aplicados os critérios de Matutes et al. e Craig e Foon para os laudos analisados, observou-se concordância em: 45,24% casos de leucemia linfoide crônica de células B/linfoma linfocítico de pequenas células B; 14,29% casos de linfoma folicular; 4,76% casos de leucemia de células pilosas; e 21,43% de casos definidos como “outras DLPCB não classificáveis por citometria de fluxo”. Entretanto, o teste de hipóteses de Hotelling (p=0,0409) mostrou haver diferença estatística para a definição das DLPCB segundo os critérios aplicados. Conclusão: Os resultados ressaltam que, mesmo sendo a citometria de fluxo importante para a caracterização das DLPCB, por vezes, o citometrista necessita incluir no laudo a categoria “outras doenças linfoproliferativas crônicas de células B não classificadas por citometria de fluxo” para induzir o prescritor a solicitar mais exames complementares.

Estudo Pioneiro sobre a Presença de Clone de Hemoglobinúria Paroxística Noturna durante Acompanhamento Terapêutico de Leucemia Aguda

Introdução: O potencial de transformação maligna de células-tronco hematopoiéticas portadoras de mutações no gene glicosilfostatidilinositol classe A (PIG-A) para leucemias agudas, embora raro, já é bem descrito na literatura. Objetivo: Neste estudo, porém, buscou-se evidenciar pela primeira vez na literatura o surgimento ou a manutenção de clones de hemoglobinúria paroxística noturna (HPN) em pacientes diagnosticados com leucemia aguda ou ainda após o início do tratamento quimioterápico. Método: A pesquisa de clones de HPN foi realizada por citometria de fluxo em blastos, hemácias, granulócitos ou monócitos de 47 amostras de sangue periférico e medula óssea de pacientes submetidos à investigação diagnóstica ou acompanhamento terapêutico, provenientes de dois hospitais oncológicos e públicos de Belém, no período de dezembro de 2017 a dezembro de 2018. Resultados: A presença de clones de HPN foi observada em 19/47 (40,4%) amostras de pacientes, em investigação diagnóstica ou acompanhamento terapêutico, que realizaram pelo menos um estudo de acompanhamento terapêutico e ainda tiveram o surgimento ou a manutenção do clone de HPN mesmo após iniciado o tratamento quimioterápico. Conclusão: Foi possível evidenciar, de forma primária, a presença de clones de HPN em pacientes diagnosticados com leucemia aguda tanto no período de investigação diagnóstica como durante o acompanhamento terapêutico, independentemente da ontogenia celular. Sem, porém, que se possa ainda avaliar a importância da presença desses clones de HPN para a evolução da doença primária, prognóstico ou necessidade de tratamento específico.

Frequency of paroxysmal nocturnal hemoglobinuria in patients attended in Belém, Pará, Brazil

BACKGROUND

Paroxysmal nocturnal hemoglobinuria is a hematological disease with complex physiopathology. It is genetically characterized by a somatic mutation in the PIG-A gene (phosphatidylinositol glycan anchor biosynthesis, class A), in which the best known antigens are DAF (decay accelerating factor or CD55) and MIRL (membrane inhibitor of reactive lysis or CD59).

OBJECTIVE

To determine the frequency of paroxysmal nocturnal hemoglobinuria in patients attended at the HEMOPA foundation from November 2008 to July 2009.

METHOD

Thirty patients, with ages ranging from two to 79 years old and suspected of having paroxysmal nocturnal hemoglobinuria were examined. All patients were immunophenotyped by flow cytometry for the CD5, CD59, CD16 and CD45 antigens.

RESULTS

Paroxysmal nocturnal hemoglobinuria was identified in nine of the thirty patients investigated. Another 3 cases had inconclusive results with CD59-negative labeling only for neutrophils. The highest frequency of paroxysmal nocturnal hemoglobinuria patients (7/9) and inconclusive cases (2/3) were between 19 years old and 48 years old, with a median of 28 years.

CONCLUSION

These results show the importance of flow cytometry to identify cases in which patients are deficient in only one antigen (CD59).

Macroscopic and histological effects of magnetic field exposition in the process of tissue reparation in Wistar rats

Exposing body tissue, in vivo, to a magnetic field promotes metabolic alterations in the cell membrane's permeability and in the apoptosis phenomenon. This aim of the study was to investigate magnetic field interactions in the process of tissue repair in rats. Twenty-four male Wistar rats, weighing 200-350 g, were assigned to one of the three different groups: Control (without exposure to the magnetic field), South Pole (with exposure to the South magnetic field), and North Pole (with exposure to the north magnetic field). The intensity of the magnetic field used was 1,600 G. All the animals were anesthetized and immobilized on a surgical board in order to receive circular wounds. The size of the wounds was measured by a milimetric paquimeter. For the histological study, the tissues were fixed in paraffin and colored with hematoxylin and eosin. Wound size data were submitted to one-way analysis of variance (ANOVA) and to the test of Student-Newman-Keuls when appropriated. The results of day 5 (F (2,23):F (3,84); P < 0.05), day 10 (F (2,23):F (8,89); P < 0.05), and day 15 (F (2,23):F (7,88); P < 0.05) revealed a significant reduction between the size of the wounds of both North and South groups when compared to Control group. Our data suggest that chronic exposure to a magnetic field of 1,600 G can accelerate the speed of tissue repair in rats.