CD4/CD8比率
資料來源：羅傑·佩博迪 / 2021 年 5 月 / aidsmap
圖片來源：Jarun Ontakrai/Shutterstock.com
CD4/CD8比率反映了免疫系統的健康狀況。
CD4 細胞（也稱為 CD4 淋巴細胞或 T 輔助細胞）透過刺激其他免疫細胞，例如巨噬細胞、B 淋巴細胞 (B 細胞 ) 和 CD8 細胞來幫助協調免疫反應來對抗感染。 未經治療的 HIV 會靶向並破壞 CD4 細胞。
CD8 細胞（也稱為 CD8 淋巴細胞或 T 抑制細胞）識別並消滅被細菌或病毒感染的細胞。
CD4/CD8 比率是透過將 CD4 細胞計數除以 CD8 細胞計數來計算的。 例如，比率為 2 表示每 1 個 CD8 細胞對應 2 個 CD4 細胞。 正常的比率在 1 到 3 之間。
CD4和病毒載量的基本信息
HIV 陰性人群的 CD4 細胞數量通常多於 CD8 細胞數量。 隨著人們年齡的增長，免疫系統對病原體的防禦能力減弱，CD4/CD8比率趨於下降。 較高的比率比較低的比率更好。
在血清轉化後的六個月內，CD4 計數通常會減少約 30%，CD8 計數可能會增加約 40%，導致倒置比率通常小於 1。透過抗反轉錄病毒治療，該比率可能會恢復到「正常」。 早期開始抗反轉錄病毒治療的人通常具有正常的 CD4/CD8 比率。
影響 CD4 計數以及隨後的 CD4/CD8 比率的因素包括一些病毒感染、結核病、皮質類固醇的使用、季節性/晝夜變化以及 CD4 分析的變化。
在 HIV 感染者的常規臨床照護中，CD4 細胞計數比 CD4/CD8 比率更重要。
此頁面的上次審核時間為 2021 年 5 月。審核截止日期為 2024 年 5 月。
CD4/CD8 ratio
Roger Pebody / May 2021 / aidsmap
Image: Jarun Ontakrai/Shutterstock.com
The CD4/CD8 ratio is a reflection of immune system health.
CD4 cells (also known as CD4 lymphocytes or T-helper cells) help coordinate the immune response by stimulating other immune cells, such as macrophages, B lymphocytes (B cells), and CD8 cells to fight infection. Untreated HIV targets and destroys CD4 cells.
CD8 cells (also known as CD8 lymphocytes or T-suppressor cells) recognise and destroy cells infected with bacteria or viruses.
The CD4/CD8 ratio is calculated by dividing the CD4 cell count by the CD8 cell count. For example a ratio of 2 would indicate that there are 2 CD4 cells for every 1 CD8 cell. A normal ratio is between 1 and 3.
Basic information on CD4 and viral load
HIV-negative people generally have a greater number of CD4 cells than they have of CD8 cells. As people get older, the immune system’s defence against pathogens is weaker and the CD4/CD8 ratio tends to decrease. Having a higher ratio is better than having a low ratio.
Within six months of seroconversion, the CD4 count generally decreases about 30% and the CD8 count may increase by about 40%, resulting in an inverted ratio that is generally less than 1. With antiretroviral treatment, the ratio may revert toward ‘normal’. People who start antiretroviral treatment early on generally have a normal CD4/CD8 ratio.
Factors affecting CD4 count and subsequently the CD4/CD8 ratio are some viral infections, tuberculosis, corticosteroid use, seasonal/diurnal variations, and variations in CD4 analyses.
In usual clinical care of people living with HIV, the CD4 cell count is more important than the CD4/CD8 ratio.
This page was last reviewed in May 2021. It is due for review in May 2024.