The SARS-CoV-2 pandemic has indeed been one of the most significant problems facing the world in the last decade. It has affected (directly or indirectly) the entire population and all age groups. Children have accounted for 1.7 % to 2 % of the diagnosed cases of COVID-19. COVID-19 in children is usually associated with a mild course of the disease and a better survival rate than in adults. In this review, we investigate the different mechanisms which underlie this observation. Generally, we can say that the innate immune response of children is strong because they have a trained immunity, allowing the early control of infection at the site of entry. Suppressed adaptive immunity and a dysfunctional innate immune response is seen in adult patients with severe infections but not in children. This may relate to immunosenescence in the elderly. Another proposed factor is the different receptors for SARS-CoV-2 and their differences in expression between these age groups. In infants and toddlers, effective immune response to viral particles can be modulated by the pre-existing non-specific effect of live attenuated vaccines on innate immunity and vitamin D prophylaxis. However, all the proposed mechanisms require verification in larger cohorts of patients. Our knowledge about SARS-CoV-2 is still developing.
- MeSH
- COVID-19 imunologie patofyziologie terapie virologie MeSH
- dítě MeSH
- dospělí MeSH
- hodnocení rizik MeSH
- imunitní systém růst a vývoj patofyziologie virologie MeSH
- interakce hostitele a patogenu MeSH
- kojenec MeSH
- lidé MeSH
- mladiství MeSH
- mladý dospělý MeSH
- novorozenec MeSH
- předškolní dítě MeSH
- prognóza MeSH
- rizikové faktory MeSH
- SARS-CoV-2 imunologie patogenita MeSH
- stupeň závažnosti nemoci MeSH
- věkové faktory MeSH
- vývoj dítěte * MeSH
- vývoj mladistvých * MeSH
- Check Tag
- dítě MeSH
- dospělí MeSH
- kojenec MeSH
- lidé MeSH
- mladiství MeSH
- mladý dospělý MeSH
- novorozenec MeSH
- předškolní dítě MeSH
- Publikační typ
- časopisecké články MeSH
- přehledy MeSH
1. Selection strategies for broilers must balance rapid growth with the welfare and health of animals, strategies must deal with the trade-off with other vital functions.2. Divergent selection of Japanese quail for high (HG) and low (LG) relative body weight gain between 11 and 28 days of age has been conducted to accelerate linear phase growth without influencing the final adult body weight. Higher body growth rate is often connected with a weakened immune system. Therefore, the present study explored the immunological characterisation of quail from HG and LG lines, which differ substantially in their growth rate.3. The trial evaluated the maternal investment to immunologically active substances, cell-mediated immunity stimulated by phytohaemagglutinin (PHA) injection and the acute phase of the immune response to lipopolysaccharide (LPS) administration in three different phases of early postnatal growth.4. Except for higher lysozyme activity in the LG group when compared to the HG line, the maternal investment did not differ between the two lines. Plasma antibody concentrations responded quickly to any change in growth rate in both lines. Overall, it seems that initial rapid growth of the LG line had long-lasting effects on immune responsiveness, even after the growth rate of the HG line escalated during the linear phase of growth.5. The study indicated that changes in the growth rate caused by the selection for growth in meat-type Japanese quail can influence the acute phase of the immune response and development of the immune system.
- Klíčová slova
- Immunity, Japanese quail, LPS, PHA, selection,
- MeSH
- buněčná imunita MeSH
- bursa Fabricii anatomie a histologie patologie MeSH
- Coturnix růst a vývoj imunologie MeSH
- exprese genu MeSH
- fytohemaglutininy aplikace a dávkování MeSH
- hmotnostní přírůstek imunologie MeSH
- imunitní systém růst a vývoj imunologie MeSH
- imunoglobuliny analýza MeSH
- interleukin-6 genetika MeSH
- lipopolysacharidy aplikace a dávkování MeSH
- muramidasa analýza MeSH
- protilátky krev MeSH
- slezina anatomie a histologie patologie MeSH
- vejce analýza klasifikace MeSH
- velikost orgánu MeSH
- zvířata MeSH
- Check Tag
- mužské pohlaví MeSH
- ženské pohlaví MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- Názvy látek
- fytohemaglutininy MeSH
- IgY MeSH Prohlížeč
- imunoglobuliny MeSH
- interleukin-6 MeSH
- lipopolysacharidy MeSH
- muramidasa MeSH
- phytohemagglutinin-P MeSH Prohlížeč
- protilátky MeSH
Artiodactyls possess GALT that appears in fetal life and is located at the extreme end of the ileum. These IPP contain mostly B cells and involute early in postnatal life. Rabbits have a similarly located lymphoid organ, called the sacculus rotundus. Studies in sheep and rabbits have led to the concept that the lower hindgut GALT represents primary lymphoid tissue for B cells and is necessary for normal B cell development, analogous to the bursa of Fabricius. This review traces the history of the observations and theories that have led to the existing concept concerning the role of lower GALT. We then review recent data from piglets with resected IPP that challenges the concept that the IPP is primary B cell lymphoid tissue and that artiodactyls and rabbits are members of the GALT group in the same context as gallinaceous birds. Eliminating the IPP as the primary lymphoid tissue for B cells leads to the hypothesis that the IPP acts as first-responder mucosal lymphoid tissue.
- Klíčová slova
- B cell development, B lymphocytes, Peyer's patches, lymphogenesis, mucosal immunity,
- MeSH
- apoptóza MeSH
- Artiodactyla imunologie MeSH
- B-lymfocyty cytologie imunologie MeSH
- buněčný rodokmen MeSH
- bursa Fabricii cytologie imunologie chirurgie MeSH
- druhová specificita MeSH
- gnotobiologické modely MeSH
- imunitní systém embryologie růst a vývoj MeSH
- králíci imunologie MeSH
- kur domácí imunologie MeSH
- lidé MeSH
- lymfatické uzliny cytologie imunologie MeSH
- lymfoidní tkáň cytologie imunologie chirurgie MeSH
- lymfopoéza MeSH
- mezenterium imunologie MeSH
- modely imunologické MeSH
- Peyerovy pláty cytologie imunologie chirurgie MeSH
- prasata imunologie MeSH
- savci embryologie imunologie MeSH
- střeva imunologie MeSH
- střevní sliznice embryologie růst a vývoj imunologie MeSH
- tvorba protilátek MeSH
- zvířata MeSH
- Check Tag
- králíci imunologie MeSH
- lidé MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
BACKGROUND: Mammals are essentially born germ-free but the epithelial surfaces are promptly colonized by astounding numbers of bacteria soon after birth. The most extensive microbial community is harbored by the distal intestine. The gut microbiota outnumber ~10 times the total number of our somatic and germ cells. The host-microbiota relationship has evolved to become mutually beneficial. Studies in germ-free mice have shown that gut microbiota play a crucial role in the development of the immune system. The principal aim of the present study was to elucidate whether the presence of gut microbiota and the quality of a sterile diet containing various amounts of bacterial contaminants, measured by lipopolysaccharide (LPS) content, can influence maturation of the immune system in gnotobiotic mice. RESULTS: We have found that the presence of gut microbiota and to a lesser extent also the LPS-rich sterile diet drive the expansion of B and T cells in Peyer's patches and mesenteric lymph nodes. The most prominent was the expansion of CD4+ T cells including Foxp3-expressing T cells in mesenteric lymph nodes. Further, we have observed that both the presence of gut microbiota and the LPS-rich sterile diet influence in vitro cytokine profile of spleen cells. Both gut microbiota and LPS-rich diet increase the production of interleukin-12 and decrease the production of interleukin-4. In addition, the presence of gut microbiota increases the production of interleukin-10 and interferon-gamma. CONCLUSION: Our data clearly show that not only live gut microbiota but also microbial components (LPS) contained in sterile diet stimulate the development, expansion and function of the immune system. Finally, we would like to emphasize that the composition of diet should be regularly tested especially in all gnotobiotic models as the LPS content and other microbial components present in the diet may significantly alter the outcome of experiments.
- MeSH
- aktivace lymfocytů MeSH
- buněčná diferenciace MeSH
- cytokiny metabolismus MeSH
- dieta MeSH
- gnotobiologické modely imunologie MeSH
- imunitní systém růst a vývoj mikrobiologie MeSH
- imunologická tolerance MeSH
- lipopolysacharidy metabolismus MeSH
- myši inbrední BALB C MeSH
- myši MeSH
- proliferace buněk MeSH
- regulační T-lymfocyty cytologie imunologie metabolismus MeSH
- střeva imunologie mikrobiologie MeSH
- střevní sliznice metabolismus MeSH
- Th1 buňky cytologie imunologie metabolismus MeSH
- Th2 buňky cytologie imunologie metabolismus MeSH
- zvířata MeSH
- Check Tag
- myši MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
- Research Support, N.I.H., Extramural MeSH
- Názvy látek
- cytokiny MeSH
- lipopolysacharidy MeSH
In this study, we have characterised postnatal changes in T lymphocyte subsets, especially gammadelta T lymphocytes, in blood, spleen and lymph nodes. Detection was carried out using two-colour flow cytometry and three-colour immunohistochemistry. During ontogeny, there was a significant increase in the total percentage of gammadelta T cells in the spleen and blood. In the lymph nodes, there were no age-dependent changes in the total percentage of gammadelta T cells, but the percentage of the gammadeltaTCR+CD8+ subpopulation significantly increased. The tissue distribution of gammadeltaTCR+CD8+ and gammadeltaTCR+CD8- cells in the lymph nodes is random and not collocated with a particular area of the organ. Furthermore, postnatal development was characterised by an increasing frequency of CD8+CD3+CD4-gammadeltaTCR-, which was compensated by a decreasing proportion of CD4+ lymphocytes. Double positive CD4+CD8+ lymphocytes were rare during the first month of life and a significant age-dependent increase of these cells was found in all the compartments monitored.
- MeSH
- imunitní systém růst a vývoj MeSH
- imunohistochemie MeSH
- lymfoidní tkáň cytologie růst a vývoj imunologie MeSH
- novorozená zvířata MeSH
- prasata imunologie MeSH
- průtoková cytometrie MeSH
- receptory antigenů T-buněk gama-delta imunologie MeSH
- T-lymfocyty - podskupiny cytologie imunologie MeSH
- zvířata MeSH
- Check Tag
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
- Názvy látek
- receptory antigenů T-buněk gama-delta MeSH
