In this task, you're given a paragraph from the research paper and your task is to generate a suitable title for the research paper based on the given paper. Under 100 words is a good title length.

Q: Madin Darby canine kidney (MDCK) cells were adapted to serum-free RPMI 1640 medium and used for cultivation of canine viruses. RPMI 1640 medium was supplemented with a soybean peptone, l-glutamine and antibiotics, so that the protein concentration was less than 5 g/ml (RPMI/SP medium). The resulting adapted MDCK-SP cells showed steady growth after the twenty-eighth passage in RPMI/SP medium (MDCK-SP cell culture). Canine distemper virus, canine parvovirus, canine adenoviruses and canine parainfluenza virus, which are the principal components of canine combined virus vaccines, grew in the MDCK-SP cell culture as efficiently as the parental MDCK cells cultured in the conventional Eagle's MEM containing fetal bovine serum. Consequently, the use of MDCK-SP cell culture can make current canine vaccine products much safer, of higher quality and at lower cost.

A: Growth characteristics of canine pathogenic viruses in MDCK cells cultured in RPMI 1640 medium without animal protein
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Q: Middle East respiratory syndrome (MERS) coronavirus (MERS-CoV) was originally identified in Saudi Arabia in 2012. It has caused MERS outbreaks with high mortality in the Middle East and Europe, raising a serious concern about its pandemic potential. Therefore, development of effective vaccines is crucial for preventing its further spread and future pandemic. Our previous study has shown that subcutaneous (s.c.) vaccination of a recombinant protein containing receptor-binding domain (RBD) of MERS-CoV S fused with Fc of human IgG (RBD-Fc) induced strong systemic neutralizing antibody responses in vaccinated mice. Here, we compared local and systemic immune responses induced by RBD-Fc via intranasal (i.n.) and s.c. immunization pathways. We found that i.n. vaccination of MERS-CoV RBD-Fc induced systemic humoral immune responses comparable to those induced by s.c. vaccination, including neutralizing antibodies, but more robust systemic cellular immune responses and significantly higher local mucosal immune responses in mouse lungs. This study suggests the potential of developing MERS-CoV RBD protein into an effective and safe mucosal candidate vaccine for prevention of respiratory tract infections caused by MERS-CoV.

A: Intranasal vaccination with recombinant receptor-binding domain of MERS-CoV spike protein induces much stronger local mucosal immune responses than subcutaneous immunization: Implication for designing novel mucosal MERS vaccines
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Q: Feline coronaviruses (FCoV) comprise two biotypes: feline enteric coronaviruses (FECV) and feline infectious peritonitis viruses (FIPV). FECV is associated with asymptomatic persistent enteric infections, while FIPV causes feline infectious peritonitis (FIP), a usually fatal systemic disease in domestic cats and some wild Felidae. FIPV arises from FECV by mutation. FCoV also occur in two serotypes, I and II, of which the serotype I viruses are by far the most prevalent in the field. Yet, most of our knowledge about FCoV infections relates to serotype II viruses, particularly about the FIPV, mainly because type I viruses grow poorly in cell culture. Hence, the aim of the present work was the detailed study of the epidemiologically most relevant viruses, the avirulent serotype I viruses. Kittens were inoculated oronasally with different doses of two independent FECV field strains, UCD and RM. Persistent infection could be reproducibly established. The patterns of clinical symptoms, faecal virus shedding and seroconversion were monitored for up to 10 weeks revealing subtle but reproducible differences between the two viruses. Faecal virus, i.e. genomic RNA, was detected during persistent FECV infection only in the large intestine, downstream of the appendix, and could occasionally be observed also in the blood. The implications of our results, particularly our insights into the persistently infected state, are discussed. coronavirus / experimental infection / FECV / persistence / cat

A:
Pathogenic characteristics of persistent feline enteric coronavirus infection in cats
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