scholarly journals Selective abrogation of antigen-specific human B cell responses by antigen-ricin conjugates.

1982 ◽  
Vol 156 (2) ◽  
pp. 634-639 ◽  
Author(s):  
D J Volkman ◽  
A Ahmad ◽  
A S Fauci ◽  
D M Neville
Keyword(s):  
T Cell ◽  
B Cell ◽  
Antibody Production ◽  
Specific Antibody ◽  
Mononuclear Cells ◽  
Pokeweed Mitogen ◽  
Cell Repertoire ◽  
Peripheral Blood Mononuclear ◽  
Cell Responses ◽  
B Cell Responses

The feasibility of selectively eliminating human antigen-specific B cell responses by treating cells in vitro with antigen covalently linked to a cell toxin was examined. Tetanus toxoid (TT) was conjugated to the toxin ricin via a thioether linkage. Peripheral blood mononuclear cells from recently immunized subjects were preincubated for 2 h with TT-ricin in the presence of lactose. Antigen was then removed, and the cells from recently immunized subjects were preincubated for 2 h with TT-ricin in the presence of lactose. Antigen was then removed, and the cells were stimulated with pokeweed mitogen to induce antibody production. TT-specific antibody production was completely abrogated by preincubation with TT-ricin but not by TT alone or a mixture of TT and ricin. In contrast, polyclonal immunoglobulin production was not diminished by TT-ricin. This selective abrogation was also seen when B cells alone were preincubated with TT-ricin and a source of T cell help was later provided. T cell blastogenic responses to TT remained intact after TT-ricin exposure. Thus, antigen-toxin conjugates are capable of selectively eliminating specific antibody-producing B cell clones, while leaving intact the remainder of the B cell repertoire.

scholarly journals Improved Immune Responses Against Zika Virus After Sequential Dengue and Zika Virus Infection in Humans

Viruses ◽  
2018 ◽  
Vol 10 (9) ◽  
pp. 480 ◽  
Author(s):  
Félix Delgado ◽  
Karina Torres ◽  
Jaime Castellanos ◽  
Consuelo Romero-Sánchez ◽  
Etienne Simon-Lorière ◽  
...  
Keyword(s):  
T Cell ◽  
Immune Responses ◽  
B Cell ◽  
Zika Virus ◽  
Mononuclear Cells ◽  
Denv Infection ◽  
T Cell Response ◽  
Zikv Infection ◽  
Cell Responses ◽  
B Cell Responses

The high levels of dengue-virus (DENV) seroprevalence in areas where the Zika virus (ZIKV) is circulating and the cross-reactivity between these two viruses have raised concerns on the risk of increased ZIKV disease severity for patients with a history of previous DENV infections. To determine the role of DENV preimmunity in ZIKV infection, we analyzed the T- and B-cell responses against ZIKV in donors with or without previous DENV infection. Using peripheral blood mononuclear cells (PBMCs) from donors living in an endemic area in Colombia, we have identified, by interferon (IFN)-γ enzyme-linked immunospot (ELISPOT) assay, most of the immunodominant ZIKV T-cell epitopes in the nonstructural (NS) proteins NS1, NS3, and NS5. Analyses of the T- and B-cell responses in the same donors revealed a stronger T-cell response against peptides conserved between DENV and ZIKV, with a higher level of ZIKV-neutralizing antibodies in DENV-immune donors in comparison with DENV-naïve donors. Strikingly, the potential for antibody-mediated enhancement of ZIKV infection was reduced in donors with sequential DENV and ZIKV infection in comparison with donors with DENV infection only. Altogether, these data suggest that individuals with DENV immunity present improved immune responses against ZIKV.

scholarly journals CD40 in Clinical Inflammation: From Multiple Sclerosis to Atherosclerosis

1998 ◽  
Vol 6 (3-4) ◽  
pp. 215-222 ◽  
Author(s):  
Jon D. Laman ◽  
Mark De Boer ◽  
Bert A. 'T Hart
Keyword(s):  
Multiple Sclerosis ◽  
Dendritic Cells ◽  
T Cell ◽  
B Cell ◽  
Antibody Production ◽  
Memory Formation ◽  
Isotype Switching ◽  
Cell Responses ◽  
Clinical Conditions ◽  
Antigen Presenting

The interactions of CD40 and CD40L have been known for some time to critically regulate B-cell responses with respect to proliferation, isotype switching, antibody production, and memory formation. More recent findings demonstrated that CD40 can be expressed on several other antigen-presenting cell (APC) types such as macrophages, dendritic cells, and fibroblasts. This expression of CD40 regulates T-cell-APC interaction and is centrally involved in a wide array of inflammatory events. Here, currently available data are reviewed demonstrating that CD40- CD40L interactions are operational in two chronic inflammatory clinical conditions, namely, multiple sclerosis and atherosclerosis. The functional correlates of these interactions are discussed in the light of recent other findings, shedding light on the multiple effects of CD40- CD40L interactions.

scholarly journals Analysis of CD4+ T-Cell Responses to Human Papillomavirus (HPV) Type 11 L1 in Healthy Adults Reveals a High Degree of Responsiveness and Cross-Reactivity with Other HPV Types

2002 ◽  
Vol 76 (15) ◽  
pp. 7418-7429 ◽  
Author(s):  
O. Martin Williams ◽  
Keith W. Hart ◽  
Eddie C. Y. Wang ◽  
Colin M. Gelder
Keyword(s):  
Human Papillomavirus ◽  
T Cell ◽  
In Vitro Selection ◽  
Mononuclear Cells ◽  
Ex Vivo ◽  
T Cell Responses ◽  
Cross Reactivity ◽  
Peripheral Blood Mononuclear ◽  
Cell Responses ◽  
Hpv Types

ABSTRACT Human papillomavirus type 11 (HPV-11) infection causes genital warts and recurrent respiratory papillomatosis. While there is compelling evidence that CD4+ T cells play an important role in immune surveillance of HPV-associated diseases, little is known about human CD4+ T-cell recognition of HPV-11. We have investigated the CD4+ T-cell responses of 25 unrelated healthy donors to HPV-11 L1 virus-like particles (VLP). CD4+ T-cell lines from 21 of 25 donors were established. Cell sorting experiments carried out on cells from six donors demonstrated that the response was located in the CD45RAlow CD45ROhigh memory T-cell population. To determine the peptide specificity of these responses, epitope selection was analyzed by using 95 15-mer peptides spanning the entire HPV-11 L1 protein. No single region of L1 was immunodominant; responders recognized between 1 and 10 peptides, located throughout the protein, and peptide responses fell into clear HLA class II restricted patterns. Panels of L1 peptides specific for skin and genital HPV were used to show that the L1 CD4+ T-cell responses were cross-reactive. The degree of cross-reactivity was inversely related to the degree of L1 sequence diversity between these viruses. Finally, responses to HPV-11 L1 peptides were elicited from ex vivo CD45RO+ peripheral blood mononuclear cells, demonstrating that recognition of HPV-11 was a specific memory response and not due to in vitro selection during tissue culture. This is the first study of CD4+ T-cell responses to HPV-11 in healthy subjects and demonstrates marked cross-reactivity with other skin and genital HPV types. This cross-reactivity may be of significance for vaccine strategies against HPV-associated clinical diseases.

scholarly journals Improved Immune Responses against Zika Virus after Sequential Dengue and Zika Virus Infection in Human

2018 ◽  
Author(s):  
Felix G. Delgado ◽  
Karina I. Torres ◽  
Jaime E. Castellanos ◽  
Consuelo Romero-Sánchez ◽  
Etienne Simon-Lorière ◽  
...  
Keyword(s):  
T Cell ◽  
Immune Responses ◽  
B Cell ◽  
Zika Virus ◽  
Neutralizing Antibodies ◽  
Denv Infection ◽  
T Cell Response ◽  
Zikv Infection ◽  
Cell Responses ◽  
B Cell Responses

The high level of dengue virus (DENV) seroprevalence in areas where Zika virus (ZIKV) is circulating and the cross-reactivity between these two viruses have raised concerns on the risk of increased ZIKV disease severity for patients with a history of previous DENV infection. To determine the role of DENV pre-immunity in ZIKV infection, we analysed the T and B cell responses against ZIKV in donors with or without previous DENV infection. Using PBMCs from donors living in an endemic area in Colombia, we have identified, by interferon (IFN)-γ enzyme-linked immunospot (ELISPOT) assay, most of the immunodominant ZIKV T-cell epitopes in the non-structural proteins NS1, NS3 and NS5. Analyses of the T and B-cell responses in the same donors revealed a stronger T-cell response against peptides conserved between DENV and ZIKV, with a higher level of ZIKV-neutralizing antibodies in DENV-immune donors, in comparison with DENV-naïve donors. Strikingly, the potential for antibody mediated enhancement of ZIKV infection was reduced in donors with sequential DENV and ZIKV infection in comparison with donors with DENV infection only. Altogether, these data suggest that individuals with DENV immunity present improved immune responses against ZIKV.

Costimulation through the inducible costimulator ligand is essential for both T helper and B cell functions in T cell–dependent B cell responses

10.1038/ni947 ◽  
2003 ◽  
Vol 4 (8) ◽  
pp. 765-772 ◽  
Author(s):  
Tak W Mak ◽  
Arda Shahinian ◽  
Steve K Yoshinaga ◽  
Andrew Wakeham ◽  
Louis-Martin Boucher ◽  
...  
Keyword(s):  
T Cell ◽  
B Cell ◽  
T Helper ◽  
Cell Functions ◽  
Cell Responses ◽  
Inducible Costimulator ◽  
B Cell Responses
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