Technical influences on immunophenotyping by flow cytometry The effect of time and temperature of storage on the viability of lymphocyte subsets

Impact of blood processing variations on natural killer cell frequency, activation, chemokine receptor expression and function

“…This finding is consistent with similar reported effects on T-cells (Nicholson et al, 1984; Ekong et al, 1993; Betensky et al, 2000; Lin et al, 2002; Berhanu et al, 2003; Bull et al, 2007; Meier et al, 2008; McKenna et al, 2009). With NK cells, the expression of both CCR4 and CCR7 diminishesover time.…”

“…Likewise, delays in the time from venipuncture to sample processing altered the phenotype or functional responses of leukocytes. Ekong and colleagues found that delays in processing PBMC reduced T-cell frequencies (Ekong et al, 1993) and others have reported impaired T-cell responses as measured by cytokine secretion or proliferation (Betensky et al, 2000; Bull et al, 2007; Kierstead et al, 2007; McKenna et al, 2009; Weinberg et al, 2009). As a potential mechanism to explain these findings, McKenna and colleagues (McKenna et al, 2009) recently demonstrated that delayed processing of blood increased the frequency of activated CD11bpos and CD15pos granulocytes, and that these leukocytes inhibited T-cell responses.…”

Optimal cellular preservation for high dimensional flow cytometric analysis of multicentre trials

“…The numbers of studies analyzing the impact of shipment on fluctuating temperatures on flow cytometry analysis is limited and were mainly done on controlled temperature to mimic shipment conditions (Antonenas et al, 2006;Ekong et al, 1993). Studies conducted by Ahmann et al (2008) showed that tissue sample shipment on dry ice within USA did not have a drastic impact on plasma cell isolation, viability and RNA integrity.…”

Maturational Changes in Peripheral Lymphocyte Subsets Pertinent to Monitoring Human Immunodeficiency Virus-Infected Chinese Pediatric Patients

“…With an impending maternal screening program and the availability of highly active ART, we also expect that the number of HIV-infected pediatric individuals will take some time to accumulate. Second, variations in flow cytometry methods which may lead to erroneous interpretation of test results have been well described (12,25), although we endeavored to overcome this problem by adopting standardized and quality-controlled laboratory procedures. Third, our study cohort consisted of a group who had been given hepatitis B vaccine whose long-term effects on the immune system with respect to the HIV disease markers are practically unknown, although we assume that the effects should be minimal.…”