The Azoospermia Factor c (AZFc) region on the Y chromosome long arm is one of the least stable regions in the human genome. It consists almost entirely of very long repeats and is prone to rearrangement. Numerous structures at AZFc have been identified, and some of them have been reported to be associated with male infertility. We screened 580 Han Chinese in Taiwan for AZFc deletion and duplication using three PCR assays, and characterized the DAZ genes in selected subjects with additional Southern analyses. About 9.5% of our subjects have AZFc partial deletion, 2.8% have partial deletion followed by duplication, and 1.7% have partial duplication. The overall rearrangement frequencies vary significantly between different Y chromosome haplogroups (Yhgs), ranging from 2.9% in O3e to 100% in N and Q. All individuals in Yhg-N lack the sY1191 marker, but one out of three of them actually have four DAZ genes, indicating further duplication after the b2/b3 deletion. Our additional screening of 142 oligospermic men and 107 fertile controls found no significant difference in the frequencies of the gr/gr and the b2/b3 deletion. However, the frequency of AZFc partial duplication in the infertile group (7.0%) was significantly higher than that in the fertile control group (0.9%) and the general Taiwanese population (1.7%). Our results indicate that AZFc partial deletion and partial duplication are common polymorphisms in Han Chinese, and that the AZFc partial duplication, but not the AZFc partial deletion, is a risk factor for male infertility in the Taiwanese population.

The 2009 H1N1 pandemic and recent human cases of H5N1, H7N9, and H6N1 in Asia highlight the need for a universal influenza vaccine that can provide cross-strain or even cross-subtype protection. Here, we show that recombinant monoglycosylated hemagglutinin (HA mg ) with an intact protein structure from either seasonal or pandemic H1N1 can be used as a vaccine for cross-strain protection against various H1N1 viruses in circulation from 1933 to 2009 in mice and ferrets. In the HA mg vaccine, highly conserved sequences that were originally covered by glycans in the fully glycosylated HA (HA fg ) are exposed and thus, are better engulfed by dendritic cells (DCs), stimulated better DC maturation, and induced more CD8+ memory T cells and IgG-secreting plasma cells. Single B-cell RT-PCR followed by sequence analysis revealed that the HA mg vaccine activated more diverse B-cell repertoires than the HA fg vaccine and produced antibodies with cross-strain binding ability. In summary, the HA mg vaccine elicits cross-strain immune responses that may mitigate the current need for yearly reformulation of strain-specific inactivated vaccines. This strategy may also map a new direction for universal vaccine design.glycoprotein engineering | broadly neutralizing antibody H

Each year influenza virus infections cause hundreds of thousands of deaths worldwide and a significant level of morbidity with major economic burden. At the present time, vaccination with inactivated virus vaccine produced from embryonated chicken eggs is the most prevalent method to prevent the infections. However, current influenza vaccines are only effective against closely matched circulating strains and must be updated and administered yearly. Therefore, generating a vaccine that can provide broad protection is greatly needed for influenza vaccine development. We have previously shown that vaccination of the major surface glycoprotein hemagglutinin (HA) of influenza virus with a singleN-acetylglucosamine at each of the N-glycosylation sites [monoglycosylated HA (HAmg)] can elicit better cross-protection compared with the fully glycosylated HA (HAfg). In the current study, we produced monoglycosylated inactivated split H1N1 virus vaccine from chicken eggs by the N-glycosylation process inhibitor kifunensine and the endoglycosidase Endo H, and intramuscularly immunized mice to examine its efficacy. Compared with vaccination of the traditional influenza vaccine with complex glycosylations from eggs, the monoglycosylated split virus vaccine provided better cross-strain protection against a lethal dose of virus challenge in mice. The enhanced antibody responses induced by the monoglycosylated vaccine immunization include higher neutralization activity, higher hemagglutination inhibition, and more HA stem selectivity, as well as, interestingly, higher antibody-dependent cellular cytotoxicity. This study provides a simple and practical procedure to enhance the cross-strain protection of influenza vaccine by removing the outer part of glycans from the virus surface through modifications of the current egg-based process.

Klinefelter syndrome (KS), characterized by the presence of more than one X-chromosome in men, is a major genetic cause of male infertility. Germ cell degeneration in KS patients is thought to be the consequences of overexpression of some genes on the X-chromosome. However, the identity of these genes and the underlying mechanisms remain unclear. Testis-expressed 11 (TEX11) is an X-chromosome-encoded germ-cell-specific protein that is expressed most abundantly in spermatogonia and early spermatocytes in the testes. In our search for TEX11-interacting partners using the yeast two-hybrid system, we identified hematopoietic pre-B cell leukemia transcription factor-interacting protein (HPIP), which anchors estrogen receptors (ER) to the cytoskeleton and modulates their functions. We found that mouse spermatogonial stem cells expressed Tex11, Hpip, and Esr2 but not Esr1. In cultured cells, TEX11 competed with ERβ for binding to HPIP. Upon treatment with 17β-estradiol or an ERβ agonist diarylpropionitrile, TEX11 promoted the nuclear translocation of ERβ and enhanced its transcriptional activities. On the other hand, TEX11 suppressed the nongenomic activities of ERβ in the cytoplasm, as indicated by reduced phosphorylation of AKT and ERK signaling molecules. Overexpression of TEX11 in mouse germ-cell-derived GC-1 and GC-2 cells suppressed the cell proliferation and the expression of cFos, Ccnd1, and Ccnb1 that were stimulated by 17β-estradiol or diarylpropionitrile and elevated the expression level of the proapoptotic Bax gene. The negative effect of TEX11 on cell proliferation suggests that increased expression of TEX11 in the germ cells may partially contribute to the spermatogenic defect observed in KS patients.