Pathogenesis of mastitis and mammary gland immunity: where we are and where we should go

The large availability of new molecular techniques and, more generally, the advances in research tools could induce a deeper knowledge on very specific aspects, but also increase the risk of missing the overall picture. Therefore, there is a strong need for an increased integration of the researches on the modulation of mammary gland immunity. The development of DNA vaccines to prevent S. aureus mastitis is presented as an example on how an integration of available knowledge and a broader cooperation among research groups would improve the efficiency of the development process. The development of vaccine based on plasmid DNA could increase the efficiency of vaccine production, reducing costs; they are easy to store, handle, administer; they can induce persistent cell-mediated immunity without the need for adjuvants; they can include multiple antigens. The future research should be directed to collect more data to identify antigens closely related to bacteria pathogenicity; to identify the proper molecules to increase antibody response; to identify molecules that could enhance non-specific (cellular) immune response; to identify effective and easy way of administration; to develop in vivo model to assess the activity of these substances, taking in account the variability of cow physiological and immunological status.