Books on the topic 'B-1 B cells'

Synovial pathology is seen in a variety of disease states, including rheumatoid arthritis (RA), osteoarthritis (OA), psoriatic arthritis, and systemic lupus erythmatosus (SLE). This chapter highlights recent advances that characterize the cellular composition of these tissues according to surface markers and chemokine and cytokine expression, and describes synovial functional status and response to therapeutics. In RA, after initiation, pannus migrates over and under cartilage, and into subchondral bone, in a destructive process. Cartilage-pannus junction (CPJ) is characterized as invasive or 'quiescent' or 'indistinct'. Invasive CPJ can comprise macrophages, fibroblast-like synoviocytes (FLS), mast cells, and/or neutrophils. CPJ activity is related to the state of activation of the overlying subintima. Subintimal inflammation can be graded to a variety of degrees (I–IV) according to established criteria and is illustrated. In some RA synovia, cellular aggregates organize into ectopic lymphoid structures (ELS) through the expression of lymphorganogenic signals, to exhibit T- or B-cell zones accompanied by dendritic cells and lymphangiogenesis. ELS synthesize rheumatoid factor (RF) and anti-citrullinated peptide antibodies (ACAP), considered to be indicative of aggressive disease. The selective cellular expression of macrophage and dendritic cell chemokines and cytokines such as TNF, GMCSF, TGFβ‎, IL-1, IL-6, IL-23, and chemokines can be seen in synovia, to form a regulated and cooperative environment that sustains the cellular organization and pathological function. Important to this process are FLS and CD68+ macrophages. CD68 expression correlates with disease severity and can be useful as a surrogate marker of disease modifying activity of therapeutics, such as anti-TNF and anti-B-cell biologics.

Systemic lupus erythematosus (SLE) is an autoimmune disease characterized by the presence of immune dysregulation, autoreactive B and T cells, and the production of a broad, heterogeneous group of autoantibodies (autoAb). The pathogenesis of lupus can be divided into three stages: 1) genetic predisposition and environmental exposures, 2) loss of tolerance, and 3) immune activation. In this chapter we will discuss the aetiopathogenesis of systemic lupus erythematosus with emphasis placed on key autoantibodies, cytokines, the innate and adaptive immune system, tolerance, NETosis, genetics and epigenetics, environmental triggers and the role of gender.

The non-Hodgkin lymphomas (NHL) are a heterogeneous group of over forty lymphoid neoplasms that have undergone a major redefinition over the last twenty-five years, in part due to advances in immunology and genetics as well as implementation of the WHO classification system. NHLs are considered clonal tumors of B-cells, T-cells, or natural killer (NK) cells arrested at various stages of differentiation, regardless of whether they present in the blood (lymphoid leukemia) or lymphoid tissues (lymphoma). In the United States, the age-standardized NHL incidence rate (per 100,000) doubled from 1973 (10.2) to 2004 (21.4) and then stabilized, while five-year relative survival rates improved from 42% in 1973 to 70% in 2004. Established risk factors for NHL or specific NHL subtypes include infectious agents (HTLV-1, HIV, EBV, HHV8, HCV, H. pylori), immune dysregulation (primary immunodeficiency, transplantation, autoimmunity, and immunosuppressive drugs), family history of lymphoma, and common genetic variants identified by genome-wide association studies.

Oral, small-molecule signalling pathway inhibitors, including ones that inhibit the JAK and SyK pathways, are currently in development for the treatment of rheumatoid arthritis (RA). Tofacitinib is an orally administered small-molecule inhibitor that targets the intracellular Janus kinase 3 and 1 (JAK1/3) molecules to a greater extent than JAK2 while baricitinib (formerly INCB028050) predominantly inhibits JAK1/2. Many of the proinflammatory cytokines implicated in the pathogenesis of RA utilize cell signalling that involves the JAK-STAT pathways and therefore inhibition of JAK-STAT signalling, by targeting multiple RA-associated cytokine pathways, has the potential to simultaneously reduce inflammation, cellular activation, and proliferation of key immune cells. Fostamatinib disodium is an orally available inhibitor of spleen tyrosine kinase (SyK), which is a cytoplasmic tyrosine kinase that is an important mediator of immunoreceptor signalling in mast cells, macrophages, neutrophils, and B cells. Interruption of SyK signalling may interrupt production of tumour necrosis factor (TNF) and metalloproteinase and therefore affect RA disease activity. Tofacitinib has been investigated in multiple phase 2 and phase 3 trials which have investigated its efficacy (clinical, functional, and radiographic) and safety in patients who have failed disease-modifying anti-inflammatory drugs (DMARDs) as monotherapy or in combination with DMARDs, compared to an inhibitor of tumour necrosis factor alpha (TNFα‎) and in patients who have failed TNFα‎ inhibitors. The efficacy of fostamatinib and baricitinib has been investigated in phase 2 trials; both are in large phase 3 clinical programmes. Each of these medications has demonstrated efficacy; their safety profile has been shown to be different from each other and from currently approved biological agents. This chapter discusses what is currently known and understood about their efficacy and safety.

The innate and the adaptive immune system efficiently cooperate to protect us from infections. The ancient innate immune system, dating back to the first multicellular organisms, utilizes phagocytic cells, soluble antimicrobial peptides, and the complement system for an immediate line of defence against pathogens. Using a limited number of germline-encoded pattern recognition receptors including the Toll-like, RIG-1-like, and NOD-like receptors, the innate immune system recognizes so-called pathogen-associated molecular patterns (PAMPs). PAMPs are specific for groups of related microorganisms and represent highly conserved, mostly non-protein molecules essential for the pathogens' life cycles. Hence, escape mutants strongly reduce the pathogen's fitness. An important task of the innate immune system is to distinguish between harmless antigens and potentially dangerous pathogens. Ideally, innate immune cells should activate the adaptive immune cells only in the case of invading pathogens. The evolutionarily rather new adaptive immune system, which can be found in jawed fish and higher vertebrates, needs several days to mount an efficient response upon its first encounter with a certain pathogen. As soon as antigen-specific lymphocyte clones have been expanded, they powerfully fight the pathogen. Importantly, memory lymphocytes can often protect us from reinfections. During the development of T and B lymphocytes, many millions of different receptors are generated by somatic recombination and hypermutation of gene segments making up the antigen receptors. This process carries the inherent risk of autoimmunity, causing most inflammatory rheumatic diseases. In contrast, inadequate activation of the innate immune system, especially activation of the inflammasomes, may cause autoinflammatory syndromes.

Eleven infectious agents (seven viruses, three parasites, and one bacterium) have been classified by the International Agency for Research on Cancer as carcinogenic to humans for one or more cancer sites: hepatitis B virus; hepatitis C virus; thirteen types of human papillomavirus (HPV); human immunodeficiency virus type 1 (HIV-1); human T-cell leukemia virus type 1; Epstein-Barr virus; Kaposi sarcoma herpesvirus; Helicobacter pylori; Opisthorchis viverrini; Clonorchis sinensis; and Schistosoma haematobium. Other infectious agents, such as Merkel cell polyomavirus, Plasmodium falciparum, and cutaneous HPVs, have been classified as “probably carcinogenic” or “possibly carcinogenic.” Accurate biomarkers of chronic infection have been essential for estimating risk and ascribing a causal role to infectious agents in cancer. Of the 14 million cases of cancer estimated to have occurred worldwide in 2012, 2.2 million were caused by infectious agents. Vaccination and screen-and-treat programs have the potential for greatly reducing the burden of cancer caused by infections.

Bones are multifunctional passive organs of movement that supports soft tissue and directly attached muscles. They also protect internal organs and are a reserve of calcium, phosphorus and magnesium. Each bone is covered with periosteum, and the adjacent bone surfaces are covered by articular cartilage. Histologically, the bone is an organ composed of many different tissues. The main component is bone tissue (cortical and spongy) composed of a set of bone cells and intercellular substance (mineral and organic), it also contains fat, hematopoietic (bone marrow) and cartilaginous tissue. Bones are a tissue that even in adult life retains the ability to change shape and structure depending on changes in their mechanical and hormonal environment, as well as self-renewal and repair capabilities. This process is called bone turnover. The basic processes of bone turnover are: • bone modeling (incessantly changes in bone shape during individual growth) following resorption and tissue formation at various locations (e.g. bone marrow formation) to increase mass and skeletal morphology. This process occurs in the bones of growing individuals and stops after reaching puberty • bone remodeling (processes involve in maintaining bone tissue by resorbing and replacing old bone tissue with new tissue in the same place, e.g. repairing micro fractures). It is a process involving the removal and internal remodeling of existing bone and is responsible for maintaining tissue mass and architecture of mature bones. Bone turnover is regulated by two types of transformation: • osteoclastogenesis, i.e. formation of cells responsible for bone resorption • osteoblastogenesis, i.e. formation of cells responsible for bone formation (bone matrix synthesis and mineralization) Bone maturity can be defined as the completion of basic structural development and mineralization leading to maximum mass and optimal mechanical strength. The highest rate of increase in pig bone mass is observed in the first twelve weeks after birth. This period of growth is considered crucial for optimizing the growth of the skeleton of pigs, because the degree of bone mineralization in later life stages (adulthood) depends largely on the amount of bone minerals accumulated in the early stages of their growth. The development of the technique allows to determine the condition of the skeletal system (or individual bones) in living animals by methods used in human medicine, or after their slaughter. For in vivo determination of bone properties, Abstract 10 double energy X-ray absorptiometry or computed tomography scanning techniques are used. Both methods allow the quantification of mineral content and bone mineral density. The most important property from a practical point of view is the bone’s bending strength, which is directly determined by the maximum bending force. The most important factors affecting bone strength are: • age (growth period), • gender and the associated hormonal balance, • genotype and modification of genes responsible for bone growth • chemical composition of the body (protein and fat content, and the proportion between these components), • physical activity and related bone load, • nutritional factors: – protein intake influencing synthesis of organic matrix of bone, – content of minerals in the feed (CA, P, Zn, Ca/P, Mg, Mn, Na, Cl, K, Cu ratio) influencing synthesis of the inorganic matrix of bone, – mineral/protein ratio in the diet (Ca/protein, P/protein, Zn/protein) – feed energy concentration, – energy source (content of saturated fatty acids - SFA, content of polyun saturated fatty acids - PUFA, in particular ALA, EPA, DPA, DHA), – feed additives, in particular: enzymes (e.g. phytase releasing of minerals bounded in phytin complexes), probiotics and prebiotics (e.g. inulin improving the function of the digestive tract by increasing absorption of nutrients), – vitamin content that regulate metabolism and biochemical changes occurring in bone tissue (e.g. vitamin D3, B6, C and K). This study was based on the results of research experiments from available literature, and studies on growing pigs carried out at the Kielanowski Institute of Animal Physiology and Nutrition, Polish Academy of Sciences. The tests were performed in total on 300 pigs of Duroc, Pietrain, Puławska breeds, line 990 and hybrids (Great White × Duroc, Great White × Landrace), PIC pigs, slaughtered at different body weight during the growth period from 15 to 130 kg. Bones for biomechanical tests were collected after slaughter from each pig. Their length, mass and volume were determined. Based on these measurements, the specific weight (density, g/cm3) was calculated. Then each bone was cut in the middle of the shaft and the outer and inner diameters were measured both horizontally and vertically. Based on these measurements, the following indicators were calculated: • cortical thickness, • cortical surface, • cortical index. Abstract 11 Bone strength was tested by a three-point bending test. The obtained data enabled the determination of: • bending force (the magnitude of the maximum force at which disintegration and disruption of bone structure occurs), • strength (the amount of maximum force needed to break/crack of bone), • stiffness (quotient of the force acting on the bone and the amount of displacement occurring under the influence of this force). Investigation of changes in physical and biomechanical features of bones during growth was performed on pigs of the synthetic 990 line growing from 15 to 130 kg body weight. The animals were slaughtered successively at a body weight of 15, 30, 40, 50, 70, 90, 110 and 130 kg. After slaughter, the following bones were separated from the right half-carcass: humerus, 3rd and 4th metatarsal bone, femur, tibia and fibula as well as 3rd and 4th metatarsal bone. The features of bones were determined using methods described in the methodology. Describing bone growth with the Gompertz equation, it was found that the earliest slowdown of bone growth curve was observed for metacarpal and metatarsal bones. This means that these bones matured the most quickly. The established data also indicate that the rib is the slowest maturing bone. The femur, humerus, tibia and fibula were between the values of these features for the metatarsal, metacarpal and rib bones. The rate of increase in bone mass and length differed significantly between the examined bones, but in all cases it was lower (coefficient b <1) than the growth rate of the whole body of the animal. The fastest growth rate was estimated for the rib mass (coefficient b = 0.93). Among the long bones, the humerus (coefficient b = 0.81) was characterized by the fastest rate of weight gain, however femur the smallest (coefficient b = 0.71). The lowest rate of bone mass increase was observed in the foot bones, with the metacarpal bones having a slightly higher value of coefficient b than the metatarsal bones (0.67 vs 0.62). The third bone had a lower growth rate than the fourth bone, regardless of whether they were metatarsal or metacarpal. The value of the bending force increased as the animals grew. Regardless of the growth point tested, the highest values were observed for the humerus, tibia and femur, smaller for the metatarsal and metacarpal bone, and the lowest for the fibula and rib. The rate of change in the value of this indicator increased at a similar rate as the body weight changes of the animals in the case of the fibula and the fourth metacarpal bone (b value = 0.98), and more slowly in the case of the metatarsal bone, the third metacarpal bone, and the tibia bone (values of the b ratio 0.81–0.85), and the slowest femur, humerus and rib (value of b = 0.60–0.66). Bone stiffness increased as animals grew. Regardless of the growth point tested, the highest values were observed for the humerus, tibia and femur, smaller for the metatarsal and metacarpal bone, and the lowest for the fibula and rib. Abstract 12 The rate of change in the value of this indicator changed at a faster rate than the increase in weight of pigs in the case of metacarpal and metatarsal bones (coefficient b = 1.01–1.22), slightly slower in the case of fibula (coefficient b = 0.92), definitely slower in the case of the tibia (b = 0.73), ribs (b = 0.66), femur (b = 0.59) and humerus (b = 0.50). Bone strength increased as animals grew. Regardless of the growth point tested, bone strength was as follows femur > tibia > humerus > 4 metacarpal> 3 metacarpal> 3 metatarsal > 4 metatarsal > rib> fibula. The rate of increase in strength of all examined bones was greater than the rate of weight gain of pigs (value of the coefficient b = 2.04–3.26). As the animals grew, the bone density increased. However, the growth rate of this indicator for the majority of bones was slower than the rate of weight gain (the value of the coefficient b ranged from 0.37 – humerus to 0.84 – fibula). The exception was the rib, whose density increased at a similar pace increasing the body weight of animals (value of the coefficient b = 0.97). The study on the influence of the breed and the feeding intensity on bone characteristics (physical and biomechanical) was performed on pigs of the breeds Duroc, Pietrain, and synthetic 990 during a growth period of 15 to 70 kg body weight. Animals were fed ad libitum or dosed system. After slaughter at a body weight of 70 kg, three bones were taken from the right half-carcass: femur, three metatarsal, and three metacarpal and subjected to the determinations described in the methodology. The weight of bones of animals fed aa libitum was significantly lower than in pigs fed restrictively All bones of Duroc breed were significantly heavier and longer than Pietrain and 990 pig bones. The average values of bending force for the examined bones took the following order: III metatarsal bone (63.5 kg) <III metacarpal bone (77.9 kg) <femur (271.5 kg). The feeding system and breed of pigs had no significant effect on the value of this indicator. The average values of the bones strength took the following order: III metatarsal bone (92.6 kg) <III metacarpal (107.2 kg) <femur (353.1 kg). Feeding intensity and breed of animals had no significant effect on the value of this feature of the bones tested. The average bone density took the following order: femur (1.23 g/cm3) <III metatarsal bone (1.26 g/cm3) <III metacarpal bone (1.34 g / cm3). The density of bones of animals fed aa libitum was higher (P<0.01) than in animals fed with a dosing system. The density of examined bones within the breeds took the following order: Pietrain race> line 990> Duroc race. The differences between the “extreme” breeds were: 7.2% (III metatarsal bone), 8.3% (III metacarpal bone), 8.4% (femur). Abstract 13 The average bone stiffness took the following order: III metatarsal bone (35.1 kg/mm) <III metacarpus (41.5 kg/mm) <femur (60.5 kg/mm). This indicator did not differ between the groups of pigs fed at different intensity, except for the metacarpal bone, which was more stiffer in pigs fed aa libitum (P<0.05). The femur of animals fed ad libitum showed a tendency (P<0.09) to be more stiffer and a force of 4.5 kg required for its displacement by 1 mm. Breed differences in stiffness were found for the femur (P <0.05) and III metacarpal bone (P <0.05). For femur, the highest value of this indicator was found in Pietrain pigs (64.5 kg/mm), lower in pigs of 990 line (61.6 kg/mm) and the lowest in Duroc pigs (55.3 kg/mm). In turn, the 3rd metacarpal bone of Duroc and Pietrain pigs had similar stiffness (39.0 and 40.0 kg/mm respectively) and was smaller than that of line 990 pigs (45.4 kg/mm). The thickness of the cortical bone layer took the following order: III metatarsal bone (2.25 mm) <III metacarpal bone (2.41 mm) <femur (5.12 mm). The feeding system did not affect this indicator. Breed differences (P <0.05) for this trait were found only for the femur bone: Duroc (5.42 mm)> line 990 (5.13 mm)> Pietrain (4.81 mm). The cross sectional area of the examined bones was arranged in the following order: III metatarsal bone (84 mm2) <III metacarpal bone (90 mm2) <femur (286 mm2). The feeding system had no effect on the value of this bone trait, with the exception of the femur, which in animals fed the dosing system was 4.7% higher (P<0.05) than in pigs fed ad libitum. Breed differences (P<0.01) in the coross sectional area were found only in femur and III metatarsal bone. The value of this indicator was the highest in Duroc pigs, lower in 990 animals and the lowest in Pietrain pigs. The cortical index of individual bones was in the following order: III metatarsal bone (31.86) <III metacarpal bone (33.86) <femur (44.75). However, its value did not significantly depend on the intensity of feeding or the breed of pigs.

Cyclophosphamide and plasma exchange are the standard of care in rapidly progressive glomerulonephritis or lung haemorrhage caused by antiglomerular basement membrane (anti-GBM) disease, and it is unusual to encounter patients at earlier stages. Steroids are universally used in addition. There is some evidence that plasma exchange may not be a critical part of treatment at an earlier stage. There is no more than anecdotal evidence for other therapies. Slower-onset therapies such as antibodies to B cells are rarely appropriate. If untreated, patients with severe anti-GBM disease will not recover renal function and are at risk of pulmonary haemorrhage. Evidence for the pathogenicity of circulating anti-GBM antibodies provides rationale for removal of circulating antibodies as rapidly as possible, whilst simultaneously inhibiting their synthesis. This was behind the introduction of the combination of plasma exchange with immunosuppressive therapy in mid 1970s, which revolutionized outcomes. Plasmapheresis aims to remove circulating pathogenic antibodies against GBM and possibly other mediators; cyclophosphamide prevents further synthesis of autoantibodies; and steroids act as anti-inflammatory agents to attenuate the glomerular inflammatory response initiated by anti-GBM antibodies. It is clear from experimental models and occasional observations in man that the anti-cell mediated effects of current therapies are important too. Outcomes vary, but in general patient survival is now good, while renal survival remains poor, in many series less than 50% at 1 year. Treatment is toxic and after an early peak in deaths due to pulmonary haemorrhage, secondary infections are the next threat. It may therefore be best not to immunosuppress patients with a very poor renal prognosis who appear to be at low risk of pulmonary haemorrhage. Treatment can usually be curtailed after 3 months without recurrence. ANCA and anti-GBM antibodies occur together in some patients. This is typically an older group which often has features of vasculitis, and the anti-GBM response may often be secondary. Longer treatment as for small vessel vasculitis is usually indicated.

Fungal respiratory infections are important causes of morbidity and mortality in immunocompromised patients. Invasive aspergillosis remains the most common invasive fungal infection whereas other filamentous fungi, such as Fusarium spp., Mucorales, and Scedosporium spp., are increasing in frequency, particularly in neutropenic hosts. Endemic mycoses, including those due to Histoplasma capsulatum, Coccidioides spp., and Talaromyces marneffei, are increasingly prevalent in patients with cell-mediated immunodeficiencies in respective geographic regions. Culture remains the gold standard of diagnosis but has limited sensitivity and often requires invasive procedures. Non-invasive diagnostic tests, including the serum sandwich enzyme immunoassay for the detection of galactomannan, the (1→3)-β‎-D-glucan assay, and molecular amplification methods have been developed to facilitate early and accurate diagnosis. Successful therapy depends upon early initiation of antifungal agents and reversal of immunosuppression. Lipid formulations of amphotericin B and newer generation triazoles including voriconazole, posaconazole, and isavuconazole have expanded the ability to treat multi-drug resistant pathogens more effectively and with less toxicity.

Minimal change disease is characteristically responsive to high-dose corticosteroids. As this is the most common cause of nephrotic syndrome in children, and responses are usually prompt, response to 60 mg/m2/day of oral prednisolone (max. 80 mg) is often used as a diagnostic test. Adults respond more slowly and have a wider differential diagnosis, and often a high risk of side effects, so therapy is not recommended without confirmation by renal biopsy. Then first-line treatment is again prednisolone or prednisone, at 1 mg/kg/day (max. 60 mg). KDIGO and other treatment protocols recommend 6 weeks treatment at full dose then 6 weeks at half dose. Shorter protocols seem to increase the risk of relapse. Children frequently have a relapsing pattern of disease which may be managed by less extreme steroid exposure, but for which second-line therapies may be needed to avoid severe steroid side effects. This can arise in adults too. Some children and adults have steroid-dependent or steroid-resistant disease, leading to earlier initiation of treatment with second-line agents. These include levamisole, calcineurin inhibitors, mycophenolate mofetil, and anti-B cell antibodies. The evidence for these and recommendations for relapsing/resistant disease are given in this chapter.