The Pathology and Pathogenesis of Mycobacterium bovis Infection 135
9.7 Concluding RemarksThere are many studies on the pathology of
M. bovis infection in a variety of animals in the
literature. Some aspects of the disease are well
understood, but others are not. M. bovis can
induce a disease indistinguishable from M. tuber-
culosis infection in man and the study of M. bovis
infection in animals has been invaluable to
understand the pathogenesis of human tuber-
culosis and vice versa. The hallmark lesion
induced by pathogenic mycobacteria in the host
is the granuloma, a dynamic structure with a
continuous movement of cells into and out of
the structure, orchestrated by the host as well as
by the pathogen (Ramakrishnan, 2012). Differ-
ential cell composition, bacterial burden and
cytokine expression patterns at the protein and
mRNA levels may result from the independent
nature of the granuloma microenvironment
(Orme and Basaraba, 2014). With new
molecular techniques available linked to ‘classic’
pathology, thorough studies can now be per-
formed to maximize the outputs and compare
the changes occurring in different granulomas
within different organs and structures from one
single animal. New pathology data coming from
domestic animals and wildlife reservoirs will be
very valuable to produce new control strategies
of tuberculosis disease induced by M. bovis in dif-
ferent epidemiological scenarios.AcknowledgementsThe author would like to acknowledge UE FP7
grant 228394 NADIR, Defra (SE3227), as well
as many colleagues at the TB research group
from Animal and Plant Health Agency, the
Department of Pathology and Infectious Dis-
eases from the University of Surrey, and the ‘Red
de Recursos Faunisticos’ group from University
of Extremadura, Spain and Ingulados S.L. for
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