Every army needs a commander — someone who doesn’t fight directly but makes sure everyone else is doing their job. In your immune system, that role belongs to the T-helper cells (Th cells).
Without them, the immune system army would be disorganized and weak.
🔬 What are T-Helper Cells?
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A type of T-lymphocyte (white blood cell).
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Mature in the thymus gland (that’s where the “T” comes from).
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Belong to the adaptive immune system.
📢 What Do T-Helper Cells Do?
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Command & Control → release chemical signals called cytokines to direct other cells.
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Activate B-Cells → tell them to produce antibodies.
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Activate Cytotoxic T-Cells → encourage them to attack infected cells.
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Support Macrophages → boost their ability to engulf pathogens.
🧩 Types of T-Helper Cells
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Th1 Cells → help fight viruses and bacteria (activate macrophages & cytotoxic T-cells).
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Th2 Cells → activate B-cells to produce antibodies.
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Th17 Cells → help fight fungi and extracellular bacteria.
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Regulatory T-Cells (Tregs) → prevent overreaction (stop the army from attacking your own body).
⚔️ Why “The Commanders”?
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They don’t shoot or kill directly.
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They give orders to the rest of the immune army.
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Without them, the other fighters are weaker and confused.
đź“ť GCSE & A-Level Revision Notes
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✅ T-helper cells mature in the thymus.
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✅ Release cytokines to activate B-cells, cytotoxic T-cells, and macrophages.
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✅ Different types (Th1, Th2, Th17, Tregs).
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✅ Central role in the adaptive immune system.
đź“š Exam Tip
If a question asks: “Which cells activate B-cells to produce antibodies?” → Answer: T-helper cells (via cytokines).
đź’ˇ Mnemonic: T = Thymus + Talkers (commanders).
đź”— Related
👉 Back to Main Guide: Immune System Cells
👉 Next fighter: Cytotoxic T-Cells – The Assassins
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