Isolation and propagation of bovine blood-derived macrophages using a mixed culture with bovine endothelial B46 cells.

Macrophages are innate immune cells with multiple functions such as phagocytosis, cytokine production, and antigen presentation. Since macrophages play critical roles in some bacterial infectious diseases in cattle, including tuberculosis, paratuberculosis, and brucellosis, the in vitro culturing of bovine macrophages is useful for evaluating host-pathogen interactions at the cellular and molecular levels. We have previously reported the establishment of two immortalized bovine liver sinusoidal cell lines, endothelial B46 cells and myofibroblast-like A26 cells (Cell Biology International, 40, 1372-1379, 2016). In this study, we investigated the use of these cell lines as feeder cells that support the proliferation of bovine blood-derived macrophages (BBMs). Notably, the B46 cell line efficiently acts as feeder cells for the propagation of BBMs. Compared with primary cultured vascular endothelial cells, the infinite proliferation ability of B46 cells is more beneficial for preparing confluent feeder layers. In conclusion, this study provides a simple and efficient protocol for the isolation and propagation of BBMs using a primary mixed culture of bovine whole blood with B46 feeder cells. Isolated BBMs are expected to be useful for developing in vitro models for studying the interactions between bovine pathogens and host immune cells.

Novel single-stranded, circular DNA virus identified in cats in Japan.

We detected a novel feline stool-associated circular DNA virus (FeSCV) in fecal samples from cats with diarrhea using consensus primers matching those of circovirus and cyclovirus. FeSCV is a circular DNA virus containing a genome with a total length of 2,046 nt encoding 2 open reading frames. Phylogenetic analyses indicated that FeSCV is classified into a clade different from that of circovirus and cyclovirus. Since the FeSCVs detected in several cats in the same household had genetically similar genomes, these viruses are most likely derived from the same origin.

Viral shedding and clinical status of feline-norovirus-infected cats after reinfection with the same strain.

Norovirus (NoV) infection is the most common cause of acute gastroenteritis in humans of all ages worldwide. When cats are experimentally infected with feline norovirus (FNoV), they develop symptoms of acute gastroenteritis. Therefore, FNoV infection may serve as an animal model for the disease caused by human norovirus infection. In this study, we examined whether FNoV of cats infected with genogroup GVI are protected from reinfection with the same strain. The blood anti-FNoV IgG level was inversely correlated with the viral load in stool samples and the clinical score of FNoV-infected cats, but complete prevention of reinfection was not observed. These findings were similar to the results of a reinfection experiment with NoV in human volunteers.

Complete Genome Sequences of Infectious Bronchitis Virus Genotype JP-II (GI-7) and JP-III (GI-19) Strains Isolated in Japan.

We report the complete genome sequences of strains JP/Yamanashi/93 and JP/Shimane/98, which are classified in JP-II (GI-7) and JP-III (GI-19), respectively, the major genotypes of infectious bronchitis virus (IBV) in Japan. This information will be useful for the in-depth understanding of the evolution of IBV in Japan.

[Ductal adenocarcinoma of the prostate: a report of 7 cases].

Ductal adenocarcinoma of the prostate is a rare subtype of prostatic adenocarcinoma, defined by morphological criteria as one that has papillary or cribriform architecture composed of high columnar cells with pseudostratified nuclei. We clinically evaluated 7 cases of ductal adenocarcinoma of the prostate in our hospital. The median age was 69 years old and median initial serum PSA level was 22.8 ng/ml. Two cases presented with dysuria, two with macrohematuria and one with abnormality on chest radiograph. Five cases were diagnosed on prostate biopsy, one on TUR-P and one on radical prostatectomy. Two had pure ductal adenocarcinoma and five had mixed ductal adenocarcinoma. Four had metastatic disease, and were treated by hormonal therapy. Among three with non-metastatic disease, two underwent radical prostatectomy with adjuvant radiotherapy and one underwent external beam radiotherapy with hormonal therapy. Three cases with non-metastatic disease have no biochemical recurrence. Among four with metastatic disease, one underwent chemotherapy of Docetaxel and one had found a new lesion in lung.

Genetic Analysis of the Complete S1 Gene in Japanese Infectious Bronchitis Virus Strains.

The complete nucleotide sequence of the S1 glycoprotein gene of the Japanese infectious bronchitis virus (IBV) strains was determined and genetically analyzed. A total of 61 Japanese IBV strains were classified into seven genotypes, namely GI-1, 3, 7, 13, 18, 19, and GVI-1 using the classification scheme that was proposed by Valastro et al, with three exceptions. These genotypes practically corresponded to those defined in Japan, namely Mass, Gray, JP-II, 4/91, JP-I, JP-III, and JP-IV, which have been identified through their partial nucleotide sequences containing hypervariable regions 1 and 2. In addition, three exceptive strains were considered to be derived from recombination within the S1 gene of IBV strains G1-13 and GI-19. By analyzing the amino acid polymorphism of the S1 glycoprotein among Japanese genotypes, a diversity was observed based on the genotype-specific amino acid residue, the proteolytic cleavage motif at the S1/S2 cleavage site, and the position of the potential N-glycosylation sites.

Complete Genome Sequences of Two JP-I (GI-18) Genotype Infectious Bronchitis Virus Strains Isolated from Chickens with Nephritis in Japan.

We report the complete genome sequences of two strains of JP-1 genotype (GI-18) infectious bronchitis virus (IBV) isolated from the kidneys of dead chickens in Japan in 2000 and 2017. This information will help researchers better understand the evolution and epidemiology of IBV in Japan.

Correction: Mase et al. Genetic Analysis of the Complete S1 Gene in Japanese Infectious Bronchitis Virus Strains. Viruses 2022, 14, 716.

In the original publication [...].

Establishment and characterization of the immortalized porcine lung-derived mononuclear phagocyte cell line.

Mononuclear phagocytes (MNP), including monocytes, dendritic cells (DC), and macrophages, play critical roles in innate immunity. MNP are abundant in the lungs and contribute to host defense against airborne agents and pulmonary immune homeostasis. In this study, we isolated porcine lung-derived MNP (PLuM) from primary cultures of parenchymal lung cells and then immortalized them by transferring the SV40 large T antigen gene and porcine telomerase reverse transcriptase gene using lentiviral vectors. The established cell line, immortalized PLuM (IPLuM), expressed DC/macrophage markers; i.e., CD163, CD172a, and major histocompatibility complex class II, whereas they did not express a porcine monocyte-specific marker, CD52. The expression patterns of these cell surface markers indicate that IPLuM originate from the DC/macrophage lineage rather than the monocyte lineage. The bacterial cell wall components muramyl dipeptide and lipopolysaccharide induced the production of the interleukin-1 family of pro-inflammatory cytokines in IPLuM. Phagocytotic activity was also detected by time-lapse fluorescence imaging of live cells when IPLuM were cultured in the presence of pHrodo dye-conjugated E. coli BioParticles. It is worth noting that IPLuM are susceptible to African swine fever virus infection and support the virus' efficient replication in vitro. Taken together, the IPLuM cell line may be a useful model for investigating host-agent interactions in the respiratory microenvironments of the porcine lung.

Complete Genome Sequence of Infectious Bronchitis Virus Strain JP/KH/64, Isolated in Japan.

Here, we report the complete genome sequence of infectious bronchitis virus (IBV) strain JP/KH/64, which is the reference strain for the JP-I genotype in Japan. This information should be useful for an in-depth understanding of the evolution of the JP-I genotype.

Identification of specific serotypes of fowl adenoviruses isolated from diseased chickens by PCR.

We have developed a polymerase chain reaction (PCR) assay to facilitate detection of the major disease-associated serotypes of fowl adenovirus (FAdV) including serotypes 1, 2, 4, 8a and 8b; primers were designed based on serotype-specific sequences of the hexon gene. We tested field isolates from chickens diagnosed with inclusion body hepatitis, gizzard erosion and hydropericardium syndrome together with reference FAdV strains characterized in Japan. We found that the primers were serotype specific; appropriate amplification of serotype-specific hexon genes was confirmed by sequence analysis of the PCR products. This PCR assay will be useful for detection of FAdV and for differentiation between disease-associated serotypes.

Fowl Adenoviruses Type 8b Isolated from Chickens with Inclusion Body Hepatitis in Japan.

Fowl adenovirus (FAdV) type 8b isolated from chickens with inclusion body hepatitis (IBH) in Japan from 2018 to 2019 were characterized serologically and genetically. Serologically, all isolates were well neutralized by antisera against the FAdV-8b strain, but they were not neutralized by antisera against the FAdV-8a strain. Phylogenetic analysis of the part of the hexon protein gene that includes the L1 region revealed that these isolates were all identical. They were also identical to foreign strains such as the SD1356 strain isolated in China and belonged to FAdV-8b. Furthermore, the 2018-19 Japanese IBH 8b isolates were genetically identical to the SD1356 strain by phylogenetic analysis of fiber genes, but they were different from previous Japanese 8b strains. These findings suggest that the 2018-19 Japanese IBH isolates might have been introduced from other countries.