Hello Kaled Nather Taha

You can refer to the research article below for more information on this interesting question.

Article T-cell exhaustion: Characteristics, causes and conversion

Highlights:

In each of these cases initial T-cell responses are elicited, but a spectrum of phenotypic and functional defects arises as the responding cells lose their functional capabilities in a progressive and stepwise manner. Interleukin-2 (IL-2) production is one of the first effector activities to be extinguished, followed by tumour necrosis factor-α (TNF-α) production, whereas the ability to produce interferon-γ (IFN-γ) is more resistant to inactivation Although cytotoxic functions by exhausted T cells can be difficult to measure in vitro, sensitive in vivo assays can detect some level of killing activity......

I hope this will help answer your question

Best,

Thank you very much Malcolm Nobre for your answer and guidance for this article. This is exactly what I was looking for....