C-C chemokine receptor 5 is essential for conventional NK cell trafficking and liver injury in a murine hepatitis virus-induced fulminant hepatic failure model.

BACKGROUND: Previous studies have demonstrated that natural killer (NK) cells migrated into the liver from peripheral organs and exerted cytotoxic effects on hepatocytes in virus-induced liver failure. AIM: This study aimed to investigate the potential therapeutic role of chemokine receptors in the migration of NK cells in a murine hepatitis  virus strain 3 (MHV-3)-induced fulminant hepatic failure (MHV-3-FHF) model and its mechanism. RESULTS: By gene array analysis, chemokine (C-C motif) receptor 5 (CCR5) was found to have remarkably elevated expression levels in hepatic NK cells after MHV-3 infection. The number of hepatic CCR5+ conventional NK (cNK) cells increased and peaked at 48 h after MHV-3 infection, while the number of hepatic resident NK (rNK) cells steadily declined. Moreover, the expression of CCR5-related chemokines, including macrophage inflammatory protein (MIP)-1α, MIP-1ß and regulated on activation, normal T-cell expressed and secreted (RANTES) was significantly upregulated in MHV-3-infected hepatocytes. In an in vitro Transwell migration assay, CCR5-blocked splenic cNK cells showed decreased migration towards MHV-3-infected hepatocytes, and inhibition of MIP-1ß or RANTES but not MIP-1α decreased cNK cell migration. Moreover, CCR5 knockout (KO) mice displayed reduced infiltration of hepatic cNK cells after MHV-3 infection, accompanied by attenuated liver injury and improved mouse survival time. Adoptive transfer of cNK cells from wild-type mice into CCR5 KO mice resulted in the abundant accumulation of hepatic cNK cells and aggravated liver injury. Moreover, pharmacological inhibition of CCR5 by maraviroc reduced cNK cell infiltration in the liver and liver injury in the MHV-3-FHF model. CONCLUSION: The CCR5-MIP-1ß/RANTES axis played a critical role in the recruitment of cNK cells to the liver during MHV-3-induced liver injury. Targeted inhibition of CCR5 provides a therapeutic approach to ameliorate liver damage during virus-induced acute liver injury.

[Impact of CACNA1C polymorphisms on antihypertensive efficacy of calcium channel blocker].

OBJECTIVE: To explore the relationship between genetic polymorphisms of CACNA1C that encoded the a1c subunit of the L-type calcium channel and the efficacy of calcium channel blocker (CCB, Nifedipine extended release tablet/20 mg/d) in essential hypertension (EH) patients of Han Chinese in Wenzhou. METHODS: For the enrolled 103 EH patients, Multiplex Polymerase Chain Reaction (Multi-PCR) and matrix assisted laser desorption ionization time of flight MS (MLDI-TOF MS) were performed to detect their genotypes (rs216008, rs1051375, rs2299661, rs10848683, rs215976), blood pressure (BP) after CCB monotherapy was compared among patients with different genotypes. RESULTS: (1) Blood pressure was significantly reduced in all patients post CCB (P < 0.05 vs. pre-CCB). (2) Diastolic blood pressure reduction was more significant in subjects with rs2299661 C/C genotype (wild genotype) than in subjects with rs2299661C/G and rs2299661G/G genotype (mutational genotype) [(12.46 ± 7.91) mm Hg (1 mm Hg = 0.133 kPa) vs. (7.22 ± 8.01) mm Hg and (5.93 ± 9.77) mm Hg, P < 0.05]. (3) Systolic blood pressure reduction was more significant in subjects with rs216008 C/C genotype (wild genotype) than in subjects with rs216008 C/T genotype (mutational genotype) [(20.60 ± 12.35) mm Hg vs. (13.62 ± 10.21) mm Hg, P < 0.05]. (4) Blood pressure reduction was similar between subjects with genotype of rs1051375, rs10848683 and rs215976. CONCLUSION: EH patients with wild genotype of rs2299661 and rs216008 in CACNA1C are more likely to be responders of CCB monotherapy.

[Comparing gene density and GC content between two large genomic blocks at short arm of chromosome 3].

The present paper is to investigate gene distribution at different genomic region with different local GC content. With shout-gun technology, we sequencing two sequences at 3p25.1 and 3p26.1, at genome size 328 kb and 753 kb respectively. The 328 kb sequence,with an average GC content as high as 47.57%, has high gene density (13.7 gene/100 kb). However, another sequence at 3p26.1 only includes one exon and one intron of large gene GRM7 and the coding sequence size is 11 520 bp only taking a small part (1.31%) of the whole genome region. High percentage distribution of GC-rich repeats of SINEs explain high GC genomic region at 3p25.1 and high concentration of AT-rich repeats of LINEs at 3p26.1 lead to low GC content of the region. Our results suggest isochore structure is the result of coevolution between gene and genome.

[Factors that influence direct sequencing of PCR products].

Factors influenced direct sequencing of PCR (polymerase chain reaction) products were investigated in this paper. It showed that the specialization of PCR products played a key role in their sequencing reactions and only which could be sequenced directly. It also showed that the PCR reaction residues (including dNTP, primers,and metal ion) affected badly on the sequencing quality, so the purification of PCR products was necessary before sequencing. In addition,the optimum templates amount in sequencing reaction rose with the increasing of their DNA size in a certain range.