了解艾滋病 The Science of HIV/AIDS

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2022年12月1日是第35个“世界艾滋病日”。近些年来,尽管公众对艾滋病的了解逐渐增多,但仍有相当一部分人存在一定程度的误解。知“艾”才能无碍,事实上,艾滋病可防、可控、可治,谈“艾”色变大可不必。

HIV/AIDS has taken the lives of over 39 million people worldwide, despite our efforts to prevent, treat and better understand it.

But with 35 million people currently infected, what exactly is it, and are we close to a cure?

To contract HIV, the virus must enter the bloodstream - and it's often transmitted from infected bodily fluids like blood, semen, vaginal fluids or breast milk.

Once inside the bloodstream, HIV targets a variety of cells, but most specifically the T-helper cells (CD4), which are a type of white blood cell that play an essential role in our immune system and fighting infections.

The outer envelope of HIV is covered in glycoproteins which mutate frequently, ultimately tricking the T-cell receptors to not recognize the virus.

Once attached to specific proteins on the T-cell, it begins to fuse the membranes together, and eventually enters the cell where it releases 2 viral RNA strands and 3 essential replication enzymes.

Because HIV is a retrovirus, the RNA is transcribed into DNA, represented here by a zipper of two RNA strands transcribing into DNA.

This DNA is then integrated into the host cell's genome.

This makes the T-cells treat the viral genes like their own, which causes them to make more copies of the virus.

These then leave the host cell and mature, ultimately seeking more T-cells.

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