Lymphocyte subsets in human immunodeficiency virus-unexposed Brazilian individuals from birth to adulthood

Abstract

Ethnic origin, genetics, gender and environmental factors have been shown to influence some immunologic indices, so that development of reference values for populations of different backgrounds may be necessary. We have determined the distribution of lymphocyte subsets in healthy Brazilian individuals from birth to adulthood. Lymphocyte subsets were determined using four-colour cytometry in a cross-sectional study of 463 human immunodeficiency virus-unexposed children and adults from birth through 49 years of age. Lymphocyte subsets varied according to age, as previously observed in other studies. However, total CD4+ T cell numbers were lower than what was described in the Pediatric AIDS Clinical Trials Group P1009 (PACTG P1009), which assessed an American population of predominantly African and Hispanic backgrounds until the 12-18 year age range, when values were comparable. Naïve percentages and absolute values of CD8+ T cells, as assessed by CD45RA expression, were also lower than the PACTG P1009 data for all analysed age ranges. CD38 expression on both CD4+ and CD8+ T cells was lower than the PACTG P1009 values, with a widening gap between the two studies at older age ranges. Different patterns of cell differentiation seem to occur in different settings and may have characteristic expression within each population.

Immunophenotypic Profile and Increased Risk of Hospital Admission for Infection in Infants Born to Female Kidney Transplant Recipients

“…However, it is known that azathioprine may cause Ono et al leukopenia and even myelosuppression (32). Moreover, as neutrophils tend to decline after birth (28), this reduction might also contribute to the increase in hospital admissions for infectious diseases in children with low neutrophil numbers at birth.…”

“…At birth, 16 out of 20 (80%) children in the Transplant group had low numbers of B cells; low CD4þT cells were observed in 3/20 (15%), low CD8þ T cells, in 3/20 (15%) and low NK cells, in 5/20 children (25%) (27,28). Of note, all neonates who presented with low T or NK cell numbers had also low B cell numbers.…”

Hypogammaglobulinemia in children: a warning sign to look deeply?

“…Hypogammaglobulinemia and recurrent bacterial infections are the classical manifestations of CVID . However, in children, these symptoms can also result of immaturity of the immune system, THI, UH, or other well‐defined PID disease . Identification of pathological cases is essential to implement appropriate therapy and avoid severe complications and morbi‐mortality .…”

“…Lymphocyte subsets were defined as follow: (i) B‐cell subsets, gated on CD19 + lymphocytes: naive (CD27 − IgD + ), non‐switched (CD27 + IgD + ), switched memory (CD27 + IgD − ), transitional (CD24 hi CD38 hi ), CD21 low (CD21 low CD38 low ), and plasmablast cells (CD38 +++ IgM − ). (ii) In both CD4 + and CD8 + T‐cell populations, the ‘naive’ cells were CD45RA + CCR7 + , ‘central memory’ (CM) cells were CD45RA − CCR7 + , ‘effector memory’ were CD45RA − CCR7 − , and ‘effector cells’ were CD45RA + CCR7 − (; Fig. ).…”

Managing costs in primary immunodeficiency: minimal immunophenotyping and three national references

“…Kappa coefficient between two sets of data -Brazilian(20) vs Italian(23) and Brazilian(20) vs North American…”