Time and temperature stability of T-cell subsets evaluated by a dual-platform method

Area of Science:

• Immunology
• Clinical Diagnostics

Background:

• T-cell subset enumeration is crucial for monitoring HIV infection and treatment response.
• Limited data exists on time and temperature stability for dual-platform (DP) methods compared to single-platform (SP) methods.

Purpose of the Study:

• To evaluate the impact of specimen age and temperature on T-cell subset enumeration using a DP method in HIV patients.
• To determine the reliability of DP methods for CD4 and CD8 cell counts under various storage conditions.

Main Methods:

• Peripheral blood samples from HIV patients were analyzed using a DP method at room temperature (RT) at 24, 72, and 96 hours.
• Samples were also refrigerated at 4°C and analyzed at 24, 48, and 72 hours after baseline RT analysis.
• Precision (CV) and bias (residuals) were assessed, and linear regression was used to compare testing performance.

Main Results:

• Mean coefficient of variation (CV) for absolute CD4 and CD8 counts was ≤7.3%.
• Median residuals were <30/μl, indicating minimal bias.
• Strong correlation was observed between baseline RT measurements and subsequent analyses at various time points and temperatures (RT and 4°C).

Conclusions:

• The DP methodology demonstrates robustness for T-cell subset enumeration in HIV patients.
• Results are comparable to those reported for SP methods regarding specimen aging and refrigeration.
• DP methods provide reliable measurements even when samples are stored for extended periods or refrigerated.