Immunological Disorders and Immunotherapy
Open Access

Immune Cells and their Vital Role in Health: Functions and its Types

Nikyt Floryan^{* *}Correspondence: Nikyt Floryan, Department of Immunology, Nilai University, Negeri Sembilan, Malaysia, Email:

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Description

The human body is a complex and remarkable system, equipped with various defense mechanisms to protect itself from harmful invaders like bacteria, viruses, and other pathogens. Among these defences, immune cells play a central role. These microscopic warriors patrol our bodies, constantly vigilant and ready to defend against any threats. This article discusses about world of immune cells, their types, functions, and the critical role they play in maintaining our health.

Types of immune cells

The immune system is a sophisticated network of cells, tissues, and organs that work together to protect the body [1]. Within this system, there are two primary categories of immune cells: Innate immune cells and adaptive immune cells [2].

Innate immune cells: These cells are the first responders to infections and are always ready to mount a defence [3].

Macrophages: These large, phagocytic cells engulf and digest pathogens, damaged cells, and cellular debris [4].

Neutrophils: They are the most abundant white blood cells in our body and are highly effective at engulfing and destroying bacteria.

Natural Killer (NK) cells: These cells target infected cells and cancer cells, destroying them by releasing cytotoxic molecules.

Dendritic cells: These are essential for presenting antigens to adaptive immune cells, initiating a more specific immune response.

Eosinophils and basophils: These cells are involved in allergic reactions and the defense against parasitic infections.

Adaptive immune cells: The adaptive immune system provides a highly specific and targeted response to pathogens. Adaptive immune cells include.

T lymphocytes (T cells): These cells play a central role in cellmediated immunity [5]. They can recognize specific antigens and activate immune responses.

B lymphocytes (B cells): These cells produce antibodies, proteins that bind to and neutralize pathogens [6]. They are essential for humoral immunity.

Memory cells: Both T cells and B cells can develop into memory cells, which remember specific pathogens and enable a faster response upon reinfection.

Functions of immune cells

Detecting and identifying threats: Immune cells constantly patrol the body, scanning for foreign invaders or abnormal cells [7]. They recognize these threats by detecting specific molecular patterns or antigens.

Engulfing and destroying pathogens: Innate immune cells like macrophages and neutrophils engulf pathogens and break them down, effectively neutralizing the threat.

Coordinating immune responses: Dendritic cells act as messengers between the innate and adaptive immune systems [8]. They present antigens to T cells, triggering a specific immune response.

Producing antibodies: B cells produce antibodies, which can neutralize pathogens or mark them for destruction by other immune cells.

Targeted elimination: T cells, including cytotoxic T cells, target and destroy infected or cancerous cells, while helper T cells coordinate immune responses.

Immunological memory: Memory cells ensure that the immune system can respond more rapidly and effectively if the same pathogen is encountered again in the future [9].

Importance of immune cells

These cells are essential for maintaining our health and protecting us from a wide range of diseases. Without a functional immune system, even the smallest infection could become life-threatening [10]. Immune cells play a pivotal role in preventing and controlling infections, combating cancer, and facilitating the healing process after injuries. Immune cells are the unsung heroes of our bodies, tirelessly working to protect us from harm. From the initial detection of invaders to the targeted elimination of threats, these microscopic warriors play a critical role in maintaining our health and well-being. Understanding the different types of immune cells and their functions sheds light on the intricacies of our immune system, highlighting the remarkable defence mechanisms that keep us safe from a world filled with potential threats. As the mysteries of immunology were unravelled, there is a gain in new insights into how to harness the power of our immune cells to improve health and combat diseases.

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