Browsing by Author "Levesque, Marc C"

Now showing 1 - 2 of 2
  • Thumbnail Image
    ItemOpen Access
    Polyclonal B cell differentiation and loss of gastrointestinal tract germinal centers in the earliest stages of HIV-1 infection.
    (PLoS Med, 2009-07-07) Levesque, Marc C; Moody, M Anthony; Hwang, Kwan-Ki; Marshall, Dawn J; Whitesides, John F; Amos, Joshua D; Gurley, Thaddeus C; Allgood, Sallie; Haynes, Benjamin B; Vandergrift, Nathan A; Plonk, Steven; Parker, Daniel C; Cohen, Myron S; Tomaras, Georgia D; Goepfert, Paul A; Shaw, George M; Schmitz, Jörn E; Eron, Joseph J; Shaheen, Nicholas J; Hicks, Charles B; Liao, Hua-Xin; Markowitz, Martin; Kelsoe, Garnett; Margolis, David M; Haynes, Barton F
    BACKGROUND: The antibody response to HIV-1 does not appear in the plasma until approximately 2-5 weeks after transmission, and neutralizing antibodies to autologous HIV-1 generally do not become detectable until 12 weeks or more after transmission. Moreover, levels of HIV-1-specific antibodies decline on antiretroviral treatment. The mechanisms of this delay in the appearance of anti-HIV-1 antibodies and of their subsequent rapid decline are not known. While the effect of HIV-1 on depletion of gut CD4(+) T cells in acute HIV-1 infection is well described, we studied blood and tissue B cells soon after infection to determine the effect of early HIV-1 on these cells. METHODS AND FINDINGS: In human participants, we analyzed B cells in blood as early as 17 days after HIV-1 infection, and in terminal ileum inductive and effector microenvironments beginning at 47 days after infection. We found that HIV-1 infection rapidly induced polyclonal activation and terminal differentiation of B cells in blood and in gut-associated lymphoid tissue (GALT) B cells. The specificities of antibodies produced by GALT memory B cells in acute HIV-1 infection (AHI) included not only HIV-1-specific antibodies, but also influenza-specific and autoreactive antibodies, indicating very early onset of HIV-1-induced polyclonal B cell activation. Follicular damage or germinal center loss in terminal ileum Peyer's patches was seen with 88% of follicles exhibiting B or T cell apoptosis and follicular lysis. CONCLUSIONS: Early induction of polyclonal B cell differentiation, coupled with follicular damage and germinal center loss soon after HIV-1 infection, may explain both the high rate of decline in HIV-1-induced antibody responses and the delay in plasma antibody responses to HIV-1. Please see later in the article for Editors' Summary.
  • Thumbnail Image
    ItemOpen Access
    Racial differences in the association of CD14 polymorphisms with serum total IgE levels and allergen skin test reactivity.
    (Journal of asthma and allergy, 2013-01) Wang, Zongyao; Sundy, John S; Foss, Catherine M; Barnhart, Huiman X; Palmer, Scott M; Allgood, Sallie D; Trudeau, Evan; Alexander, Katie M; Levesque, Marc C
    BACKGROUND: The CD14 C-159T single nucleotide polymorphism (SNP) has been investigated widely as a candidate genetic locus in patients with allergic disease. There are conflicting results for the association of the CD14 C-159T SNP with total serum immunoglobulin E (IgE) levels and atopy. There are limited data regarding the association of the CD14 C-159T SNP in subjects of African ancestry. The aim of the study was to determine whether the C-159T SNP and other CD14 SNPs (C1188G, C1341T) were associated with total serum IgE levels and with allergy skin test results in nonatopic and atopic subjects; as well as in Caucasian and African American subjects. METHODS: A total of 291 participants, 18-40 years old, were screened to determine whether they were atopic and/or asthmatic. Analyses were performed to determine the association between CD14 C-159T, C1188G, or C1341T genotypes with serum IgE levels and with the number of positive skin tests among Caucasian or African American subjects. RESULTS: We found no significant association of serum total IgE level with CD14 C-159T, C1188G, or C1341T genotypes within nonatopic or atopic subjects. Subjects with CD14-159 T alleles had significantly more positive allergen skin tests than subjects without CD14-159 T alleles (P = 0.0388). There was a significant association between the CD14 1188 G allele, but not the CD14 1341 T allele, with the number of positive skin-test results in Caucasians, but not in African Americans. CONCLUSION: These results support a possible association between CD14 polymorphisms and atopy. CD14-159 T or CD14 1188 G alleles were associated with atopic disease. For subjects with CD14 1188 G alleles, the association with atopic disease was stronger in Caucasians compared to African Americans.