Abstract INTRODUCTION Immunity in cancer patients is modified both by the cancer itself and by oncospecific treatments. Whether a patient’s adaptive immunity is impaired depends on their levels of naive lymphocytes and other cell populations. During the COVID-19 pandemic, cancer patients are at greater risk of progressing to severe forms of the disease and have higher mortality rates than individuals without cancer, particularly while they are receiving cancer-specific therapies. An individual’s protection against infection, their response to vaccines, and even the tests that determine the humoral immune response to SARS-CoV-2, depend on lymphocyte populations, meriting their study. OBJECTIVE Estimate blood concentrations of lymphocytes involved in the immune response to new pathogens in cancer patients. METHODS We carried out an analytical study of 218 cancer patients; 124 women and 94 men, 26–93 years of age, who were treated at the National Oncology and Radiobiology Institute in Havana, Cuba, March–June, 2020. Patients were divided into five groups: (1) those with controlled disease who were not undergoing cancer-specific treatment; (2) those undergoing debulking surgery; (3) patients undergoing chemotherapy; (4) patients undergoing radiation therapy and (5) patients currently battling infection. We evaluated the following peripheral blood lymphocyte subsets via flow cytometry: B lymphocytes (total, naive, transitional, memory, plasmablasts and plasma cells); T lymphocytes (total, helper, cytotoxic and their respective naive, activated, central memory and effector memory subsets); and total, secretory and cytotoxic natural killer cells and T natural killer cells. We also estimated neutrophil/lymphocyte ratios. Lymphocyte concentrations were associated with controlled disease and standard cancer therapy. For variables that did not fall within a normal distribution, ranges were set by medians and 2.5–97.5 percentiles. The two-tailed Mann–Whitney U test was used to measure the effect of sex and to compare lymphocyte populations. We calculated odds ratios to estimate lymphopenia risk. RESULTS All cancer patients had lower values of naive helper and cytotoxic T lymphocyte populations, naive B lymphocytes, and natural killer cells than normal reference medians. Naive helper T cells were the most affected subpopulation. Memory B cells, plasmablasts, plasma cells, activated T helper cells, and cytotoxic central memory T cells were increased. Patients undergoing treatment had lower levels of naive lymphocytes than untreated patients, particularly during radiation therapy. The risk of B lymphopenia was higher in patients in treatment. The odds ratio for B lymphopenia was 8.0 in patients who underwent surgery, 12.9 in those undergoing chemotherapy, and 13.9 in patients in radiotherapy. CONCLUSIONS Cancer and conventional cancer therapies significantly affect peripheral blood B lymphocyte levels, particularly transitional T helper lymphocytes, reducing the immune system’s ability to trigger primary immune responses against new antigens.

ABSTRACT Introduction: Lymphocyte immunophenotype changes in non-Hodgkin lymphoma patients are associated with prognosis and therapeutic responses. However, its association with the disease has not been systematically established. Therefor its contribution to the diagnosis process. Objective: To assess the association of lymphocyte immunophenotype in peripheral blood with the presence of non-Hodgkin lymphoma. Methods: 31 peripheral blood samples were analyzed from patients with a confirmed diagnosis of non-Hodgkin lymphoma and from 68 healthy individuals as controls, during the period 2018 to 2020. Multiparametric flow cytometry was used for immunophenotyping. The area under the curve and the Youden index were calculated to establish cut-off points in lymphocyte percentages. The association of immunophenotypic changes with non-Hodgkin's lymphoma was made using Odd ratio calculations. Results: The increase in TCD8+ and NKCD56dim lymphocytes from peripheral blood was significantly associated with the presence of non-Hodgkin lymphoma (OR= 3.4 and 2.9, respectively). Oppositely, the decrease in TCD4+, double positive T, double negative T and NKCD56bright lymphocytes was associated with the existence of non-Hodgkin lymphoma (OR= 23.0, 10.7, 6.9 and 15.8, respectively). Therefore, the decrease in the CD4/CD8 rate was also associated with the disease. Conclusion: The changes found in these lymphocytic immunophenotypes were significantly associated with the presence of non-Hodgkin lymphoma, which represents a systemic expression of the disease and suggests its diagnostic value.

RESUMEN Introducción: Los cambios en el inmunofenotipo de los linfocitos en los pacientes con linfoma no Hodgkin están asociados con el pronóstico y las respuestas terapéuticas. Sin embargo, no se ha establecido sistemáticamente la asociación con la enfermedad y por tanto su contribución al diagnóstico. Objetivo: Evaluar la asociación del inmunofenotipo linfocitario en sangre periférica con la presencia del linfoma no Hodgkin. Métodos: Se analizaron 31 muestras de sangre periférica de pacientes con diagnóstico confirmado de linfoma no Hodgkin y de 68 individuos sanos como controles, durante el período de 2018 a 2020. Se empleó la citometría de flujo multiparamétrica para el inmunofenotipado. Se calculó el área bajo la curva y el índice de Youden para establecer puntos de corte en los porcentajes linfocitarios. La asociación de los cambios inmunofenotípicos con el linfoma no Hodgkin, se realizó mediante cálculos de Odd ratio. Resultados: El aumento de linfocitos TCD8+ y NKCD56opaco se asoció significativamente con la presencia de linfoma no Hodgkin (OR= 3,4 y 2,9; respectivamente). Por el contrario, la disminución de linfocitos TCD4+, T doble positivo, T doble negativo y NKCD56brillante también se asoció con la existencia de linfoma no Hodgkin (OR= 23,0; 10,7; 6,9 y 15,8; respectivamente). Además, la disminución del índice CD4/CD8 también fue asociada con la enfermedad. Conclusiones: Los cambios encontrados en los inmunofenotipos linfocitarios se asociaron de forma significativa con la presencia del linfoma no Hodgkin, lo cual representa una expresión sistémica de la enfermedad y sugiere su valor diagnóstico.

Abstract The outbreak of coronavirus pneumonia in Wuhan, China, became a pandemic on March 11, 2020. It has caused almost 4 million confirmed cases worldwide, with more than 270,000 deaths. Coronavirus is an enveloped RNA virus of the β-coronavirus genus distributed in birds, humans, and other mammals. The World Health Organization has named the new disease COVID-19. The scientific community is looking for evidence that can lead to a better understanding of the infection and the immune response (IR), prognostic and therapeutic predictors, effective treatments and vaccines. The objective of this review was to compile updated scientific evidence of the IR to COVID-19, in order to guide professionals with solutions that have a clinical impact. The most important elements involve innate immunity with failures in the interferon system in the early stages of the infection and a sustained increase in proinflammatory interleukins. This can end in a potentially fatal cytokine storm. The infiltration of neutrophils and macrophages at the alveolar level, accompanied by neutrophilia, is very characteristic. Lymphopenia is evident at the adaptive immunity level, that, depending on the degree, can indicate the severity of the disease. Understanding the temporal sequence of the IR is crucial for choosing the appropriate and effective therapies, especially when selecting which type of anti-inflammatory drugs can be used and the frequency of the dosage. Due to the fact that it is difficult to determine when they will be clearly beneficial, not harmful to the IR and not too late, due to the irreversibility of the process.

Resumen El brote de neumonía por coronavirus en Wuhan, China, devino en pandemia el 11 de marzo del 2020. Ha provocado casi 4 millones de casos confirmados en todo el mundo, con más de 270 mil muertes. El coronavirus es un virus ARN envuelto del género β-coronavirus, distribuido en aves, humanos y otros mamíferos. La Organización Mundial de la Salud denominó a la nueva enfermedad COVID-19. La comunidad científica se ha volcado a la búsqueda de evidencias que permitan comprender mejor la infección y la respuesta inmunitaria (RI), para identificar predictores pronósticos y terapéuticos, así como tratamientos y vacunas eficaces. La presente revisión tuvo como objetivo la compilación actualizada de evidencias científicas de las características de la respuesta inmune en la COVID-19, y así orientar a los profesionales en su mejor comprensión y en algunas soluciones de impacto clínico. Los elementos más importantes involucran a la inmunidad innata, con fallos en el sistema de los interferones en etapas iniciales de la infección y el incremento sostenido de interleucinas proinflamatorias. Esto puede terminar en una tormenta de citocinas potencialmente fatal. El infiltrado de neutrófilos y macrófagos a nivel alveolar, acompañado de neutrofilia, es característico. En el área de la inmunidad adaptativa se evidencia una linfopenia que según el grado puede indicar la severidad de la enfermedad. Comprender la secuencia temporal de la RI permite elegir las terapias oportunas y eficaces, sobre todo al seleccionar los antiinflamatorios y el momento de su aplicación. Dado que resulta difícil determinar cuándo serán netamente beneficiosos, que no perjudiquen la RI y que no sea demasiado tarde, por la irreversibilidad del proceso.

ABSTRACT Introduction: When non-Hodgkin lymphomas infiltrate the central nervous system increases mortality. The diagnosis of this infiltration can be made by the study of cerebrospinal fluid using flow cytometry, with a higher sensitivity than conventional cytology. Objective: To estimate the relationship between the cellular immunophenotype of the cerebrospinal fluid and the overall survival of patients with non-Hodgkin lymphoma and neurological symptoms. Methods: An analytical and prospective study was conducted in 15 patients with confirmed diagnosis of non-Hodgkin lymphoma and neurological symptoms, with negative cytology of the cerebrospinal fluid. Patients cared at Oncology Department of the National Institute of Oncology and Radiobiology, during the years 2017-2018. The immunophenotype was characterized by multiparametric flow cytometry. Results: 60.0% of the patients was female and 53.4% older than 60 years. There was an overall mortality of 26.7%. 17 immunophenotypes were found, 58.9% of them was normal, 23.4% reactive and 17.7% suspected of malignancy. Overall survival advantage was obtained in patients with cerebrospinal fluid with normal immunophenotype (HR 0.04). Conclusions: Flow cytometry could discriminate cells suspected of malignancy, in patients whose cytologies were negative. The presence in the cerebrospinal fluid of atypical cells, pleocytosis and a high lymphocyte-monocyte index were associated with a lower overall survival.

RESUMEN Introducción: Los linfomas no-Hodgkin pueden infiltrar el sistema nervioso central y producir síntomas neurológicos, lo cual incrementa la mortalidad. El diagnóstico de esta infiltración se puede realizar mediante el estudio del líquido cefalorraquídeo por la técnica de citometría de flujo, con una mayor sensibilidad que la citología convencional. Objetivo: Estimar la supervivencia global de pacientes con Linfoma no-Hodgkin y síntomas neurológicos según el inmunofenotipo celular del líquido cefalorraquídeo. Métodos: Se realizó un estudio analítico y prospectivo en 15 pacientes con diagnóstico confirmado de linfoma no-Hodgkin y síntomas neurológicos, con citología negativa del líquido cefalorraquídeo, tratados en el servicio de oncología del Instituto Nacional de Oncología y Radiobiología, durante los años 2017 y 2018. El inmunofenotipo fue caracterizado mediante citometría de flujo multiparamétrica. Resultados: El 60,0 % de los pacientes fue del sexo femenino y el 53,4 % mayor de 60 años. Hubo una mortalidad del 26,7 %. Se realizaron 17 inmunofenotipos, el 58,9 % fue normal, el 23,4 % reactivo y el 17,7 % sospechoso de malignidad. La supervivencia global fue mayor en pacientes con líquido cefalorraquídeo con inmunofenotipo normal (HR. 0.04). Conclusiones: La citometría de flujo pudo discriminar células sospechosas de malignidad, en pacientes cuyas citologías fueron negativas. La presencia en el líquido cefalorraquídeo de células atípicas, de pleocitosis y de un índice de linfocito-monocito alto se asoció con una supervivencia global menor.