What Is Going on with Natural Killer Cells in HIV Infection?

Abstract

Natural killer (NK) cells represent 10–15% of circulating lymphocytes and are important mediators of both natural and adaptive immunity. They participate in immune surveillance against malignancies and virus infection and are involved in the complex immune responses of transplantation, autoimmune diseases and immunosuppression. They can also mediate physiological regulation of hematopoiesis, homeostasis of reproduction and placentation. In recent years new advances have been achieved in understanding the mechanisms whereby NK cells exert their cytotoxic and regulatory roles. Here, we review the physiology of NK cells with special attention to its role in HIV infection.

Alterations of Natural Killer Cell and T-Lymphocyte Counts in Adults Infected with Human Immunodeficiency Virus through Blood and Plasma Sold in the Past in China and in Whom Infection Has Progressed Slowly over a Long Period

“…Natural killer (NK) cells are an essential part of the immune system, representing 10 to 15% of circulating lymphocytes, and are important mediators of both natural and adaptive immunity. NK cells participate in immune surveillance against malignancies and virus infection (4,8,16,20). NK cells are CD3-negative, large granular lymphocytes that express characteristic NK cell markers such as CD56 and CD16 (7,(18)(19).…”

The innate immune system and HIV pathogenesis

“…However, the reason for this perturbation is still unclear. In addition, NK cells numbers decline with the development of general lymphopenia associated with AIDS [18]. Although the existence of a CD4+ subset of NK cells that can be infected by HIV has been reported [19], a more recent report does not seem to support this finding [17••].…”

Atividade Antileucêmica das Células Natural Killer (NK)

“…As células natural killer (NK) foram caracterizadas há mais de 30 anos como componentes importantes do sistema imune inato, que têm a capacidade de lisar células alvo, além de fornecer citocinas imunorregulatórias. As células NK compreendem cerca de 10% dos linfócitos do sangue periférico e são identificadas pela expressão de CD56 e CD16 na ausência de CD3 1,2 . Dois subtipos distintos de células NK podem ser identificados baseando-se na densidade de expressão de superfície de CD56.…”