| 1. |
- Chen, Kang, et al.
(author)
-
Immunoglobulin D enhances immune surveillance by activating antimicrobial, proinflammatory and B cell-stimulating programs in basophils
- 2009
-
In: Nature Immunology. - : Springer Science and Business Media LLC. - 1529-2908 .- 1529-2916. ; 10:8, s. 121-889
-
Journal article (peer-reviewed)abstract
- Immunoglobulin D (IgD) is an enigmatic antibody isotype that mature B cells express together with IgM through alternative RNA splicing. Here we report active T cell-dependent and T cell-independent IgM-to-IgD class switching in B cells of the human upper respiratory mucosa. This process required activation-induced cytidine deaminase (AID) and generated local and circulating IgD-producing plasmablasts reactive to respiratory bacteria. Circulating IgD bound to basophils through a calcium-mobilizing receptor that induced antimicrobial, opsonizing, inflammatory and B cell-stimulating factors, including cathelicidin, interleukin 1 (IL-1), IL-4 and B cell-activating factor (BAFF), after IgD crosslinking. By showing dysregulation of IgD class-switched B cells and 'IgD-armed' basophils in autoinflammatory syndromes with periodic fever, our data indicate that IgD orchestrates an ancestral surveillance system at the interface between immunity and inflammation.
|
|
| 2. |
- Revay, T., et al.
(author)
-
Macrocephaly in Bull Spermatozoa Is Associated with Nuclear Vacuoles, Diploidy and Alteration of Chromatin Condensation
- 2009
-
In: Cytogenetic and Genome Research. - : S. Karger. - 1424-8581 .- 1424-859X. ; 126:1-2, s. 202-209
-
Journal article (peer-reviewed)abstract
- Spermatozoa from 2 dairy AI (artificial insemination) bulls (A and B), identified by their abnormal spermiogram with cells depicting frequent macrocephaly, double tails and nuclear vacuoles, were case-investigated and compared to normal spermatozoa from a control AI sire (C). Head sizes were measured and morphological abnormalities scored using brightfield and differential interference contrast microscopy. The degree of sperm maturation and of resistance to acid-induced DNA denaturation in situ were determined after uploading of acridine orange using flow cytometry of 5,000 cells/sample. Nuclear fragmentation, i.e. the ratio of red to total (red + green) fluorescence, reached 7.1% and 31% in bulls A and B, compared to 2% in bull C. The proportion of immature spermatozoa, i.e. those with incomplete histone-protamine exchange and depicting higher green fluorescence compared to the main population of the control bull, reached 9.54% in A and 7.75% in B, compared to only 0.47% in the control. In the second part of this study the previously unknown chromosomal constitution of large-headed spermatozoa of bull A was investigated by fluorescence in situ hybridization using an X-Y painting probe set. The 7.5% XY-bearing cells and the presence of diploid spermatozoa detected by flow cytometry indicate a meiotic arrest in the first division in bull A, becoming the first proven case of association of macrocephaly and M1 diploidy. The diverse approaches used for the investigation of spermatozoal DNA provide insights into the etiology of macrocephaly. Copyright (C) 2009 S. Karger AG, Basel
|
|
| 3. |
|
|
