Tuberculosis vaccines

TLR7/8 adjuvant overcomes newborn hyporesponsiveness to pneumococcal conjugate vaccine at birth

“…Therefore, many vaccine formulations produce distinct and potentially suboptimal responses in the very young. A number of adjuvanted, including live (self-adjuvanted), vaccines induce relatively robust immunogenicity in early life: (a) in mice, measles vaccines employing DNA (32) and a live-replicating attenuated strain of Listeria monocytogenes (33) induced early protection; (b) in infant rhesus macaques, liposome adjuvant/replicon particles induce anti-measles immunity (34); and (c) in human newborns, Bacille Calmette Guérin, a live-attenuated Mycobacterium bovis vaccine that activates multiple PRRs induces robust Th1 responses at birth (35). However, to our knowledge, a molecular adjuvant that can help induce adult-level immunogenicity/protection in newborn primates had yet to be described.…”

Probable disseminated BCG infection in a 10-month-old child after BCG vaccination

“…The delay in this case was 40 d. In literature, the delays varied from weeks to months after vaccination. 1 In our case, the symptoms were made of abscessed lymph nodes, ulcerative lesions, and osteolysis, located mainly at the ipsilateral side of the injection. In literature, lesions are habitually ipsilateral to the injection.…”

“…In literature, lesions are habitually ipsilateral to the injection. 1 Disseminated BCG infection appears usually as a result of impaired immune system of the host (severe combined immunodeficiency, interferon gamma receptor deficiency, interleukin 12 deficiency, HIV infection). [2][3][4] About half of the disseminated BCG infections, regarded as idiopathic, occur without a well-defined underlying immunological defect.…”

Prospects in Mycobacterium bovis Bacille Calmette et Guérin (BCG) vaccine diversity and delivery: Why does BCG fail to protect against tuberculosis?

“…Recent studies showed that 188 T cell epitopes essential to the human immune response to M.tb infection had been lost, to varying degrees, in all BCG substrains [48]. BCG Tokyo-172 substrain had the highest number of T cell epitopes in relation to M.tb strains; however this BCG substrain has consistently induced poor immunity against TB in animal models and in clinical trials [4;40]. Thus, the number of expressed epitopes is not necessarily a good indicator for vaccine design.…”

“…In humans, at best, BCG is 80% effective in preventing TB and, in the majority of the cases protection lasts for only 10–15 years, with the exception of a study in the Native Alaskan Indians community, where protection lasted for over 50 years [3]. Conversely, complete lack of protection has also been reported in communities in India, specifically in Chengalpattu (formerly known as Chingleput) [4], thus highlighting the importance of the human genetic pool and the environment in generating protection. For unknown reasons, the protective efficacy of BCG and its duration vary according to geography and population age [2].…”