Laboratory control values for CD4 and CD8 T lymphocytes. Implications for HIV-1 diagnosis

Abstract

SUMMARYWith the advent of standard flow cytometric methods using two-colour fluorescence on satnpies of whole blood, it is possible to establish the ranges of CD3, CD4 and CD8 T lymphocyte subsets in the routine laboratory, and also to assist the definition of HIV-l-re!ated deviations from these normal values. In 676 HIV-I-seronegative individuals the lymphocyte subset percentages and absolute counts were determined. The samples taken mostly in the morning. The groups included heterosexual controls, people with various clotting disorders but without lymphocyte abnormalities as well as seronegative homosexual men as the appropriate controls for the HIV-I-infected groups. The stability of CD4"/<i and CD8'^> values was demonstrated throughout life, and in children CD4 values <25% could be regarded as abnormal. The absolute counts ofall Tcell subsetsdeereased from birth until the age of ID years. In adolescents and adults the absolute numbers {mean±s.d.) of lymphocytes, CD3. CD4 and CD8 eells were I 90 + 0-55. I 45 + 046. 083+029 and 056 + 0 23 X iO'*//, respectively. In patients with haemophilia A and B the mean values did not differ signifieantly. In homosexual men higher CD8 levels were seen compared with heterosexual men and 27"/;. had an inverted CD4/CD8 ratio but mostly without CD4 lymphopenia {CD4<04x 107/), However, some healthy uninfected people were 'physiologieally' lymphopenic without having inverted CD4/CD8 ratios. When the variations "within persons" were studied longitudinally over a 5-year period, the absolute CD4 counts tended to be fixed al different levels. As a marked contrast, over 60% of asymptomatic HIV-I ' patients exhibited low CD4 counts <04x 10"//together with inverted CD4/CD8 ratios. Such combined changes among the heterosexual and HIV-1-seronegative homosexual groups were as rare as 14% and 3%. respectively. For this reason, when the lymphoeyte tests show < 0-4 X IO**// CD4 eount and a CD4/CD8 ratio ofless than unity, the individuals need to be investigated further for ehronicity of this disorder, the signs of viral infections sueh as HIV-I and other eauses of immunodeficiency.

The low EOMES/TBX21 molecular phenotype in multiple sclerosis reflects CD56+ cell dysregulation and is affected by immunomodulatory therapies

“…Other studies have shown immune cell subset proportions in blood vary more between individuals than for the same individual over time [13,14], indicating a relatively stable phenotype. We sought novel biomarkers of such immunophenotypes using transcriptomics, and focusing on the 110 non-MHC MS susceptibility loci identified by GWAS.…”

Restoration of the CD4 T Cell Compartment after Long-Term Highly Active Antiretroviral Therapy without Phenotypical Signs of Accelerated Immunological Aging

“…The mean CD4 T cell count at start of HAART (baseline) was 688 cells/ l blood (range: 50 -2274) for children and 206 cells/ l blood (range: 19 -560) for adults. Because T cell counts per microliter of blood decrease with age and stabilize at the start of adolescence, total CD4 T cell counts, as well as counts of CD4 T cell subsets, were normalized for age-matched control values, which were derived from our cohort of healthy volunteers and were similar to values published by others (39,40). The mean normalized CD4 T cell number at the start of HAART was higher for children than for adults (39.5 and 25.7% of the age-matched control value, respectively).…”

HTLV-I infection: A dynamic struggle between viral persistence and host immunity

“…In the absence of infection, the normal CD4 þ helper T-cell count averages 850 cells/mm 3 of peripheral blood, although it is known that there is a wide variance between individuals, with healthy values in adolescents and adults ranging from 500 cells/mm 3 to 1200 cells/mm 3 (Bofill et al, 1992).…”

“…Next, it is known that CTLs of a diverse range of specificities are continuously being produced. The average level of CD8 þ cytotoxic T-lymphocytes in a normal, healthy individual is roughly 550 cells/mm 3 of peripheral blood (Bofill et al, 1992). We will assume that at the start of infection, the number of circulating CD8 þ CTLs in an individual that can recognise HTLV-I epitopes is on the order of 10 À 1 cells/mm 3 .…”