The development of lymphocytes with T- or B-membrane determinants in the lizard embryo

To study the ontogeny of lymphocytes in the lizard, Chalcides ocellatus antisera were raised in rabbits against thymocytes collected from adult lizards (AATS) or from embryos of stages 40 and 41 (AETS), and against serum immunoglobulins (AGGS). AATS recognized in adult lizards a surface membrane antigenic system (TA) specific to thymocytes and thymus-derived (T-) cells in spleen, and a distinct antigenic entity (Tt) found exclusively on intrathymic lymphocytes. After exhaustive absorption with adult thymocytes, AETS defined a further antigen (TE). On the other hand, AGGS combined with the immunoglobulin (Ig) determinants present in the cytoplasm and surface membrane of lizard presumptive B lymphocytes. Immunofluorescence assays during the development of the T and B lineage showed that TA+ and Tt+ thymocytes increased from 35% at stage 37 to 96% at stage 41, and were exported precociously to the embryonic splenic environment. Embryonic thymocytes were shown to totally lack surface Ig, whereas 40-50% of splenocytes carried cytoplasmic and/or surface membrane Ig determinants. The data revealed further the presence of a subset of splenocytes bearing the specific markers of both T and B cells.     

Membrane characteristics of established human T- and B-cell lines. Cross-reactivity of human T-antigenic determinants with peripheral lymphocytes of non-human primates and the presence of MLC antigens on cultured T-cell lines.

Human T-cell lines (MOLT-4 and SOMMER-T) were injected into rabbits and monkeys (stumptail and squirrel monkeys). Rabbit anti-MOLT serum was absorbed with human liver and cultured B cells. Absorbed anti-MOLT serum was cytotoxic to lymphocytes of baboons and stumptail monkeys. Rabbit anti-MOLT and SOMMER-T sera after absorption with liver and B cell showed florescent ring formation in baboon and stumptail lymphocytes by using immunoflurescence techniques. On the other hand, antisera against MOLT and SOMMER-T cells in stumptail and squirrel monkeys were not only cytotoxic to MOLT and SOMMER-T cells, but also to other T-cell lines, CCRF-CEM and CCRF-HSB-2 cells. Cultured B-cell lines stimulated allogeneic and xenogeneic (rabbit and monkeys) lymphocytes far better than cultured T-cells lines did. T-cell lines, CCRF-HSB-2 and SOMMER-T (number 8402), gave small but significant stimulation to allogenic lymphocytes especially in the presence of foetal calf serum. MOLT-4B failed to stimulatie allogeneic lymphocytes. When lymphocytes of non-human primates and rabbit were cultured with human B- and T-cell lines in the presence of foetal calf serum, CCRF-HSB-2 and SOMMER-T cells stimulated xenogeneic lymphocytes of rabbit, squirrel monkey and stumptail monkey. MOLT-4 cells stimulated lymphocytes of baboon to some extent. These results indicate that although cultured B-cell lines had more mixed lyphocyte reaction (MLR) stimulating structure than T-cell lines, the latter still maintained some stimulating structure on the membrances.     

Evidence of early development of action planning in the human foetus: a kinematic study

The aim of the present study was to investigate whether foetal hand movements are planned and how they are executed. We performed a kinematic analysis of hand movements directed towards the mouth and the eyes in the foetuses of eight women with normally evolving pregnancies. At 14, 18 and 22 weeks of gestation, eight foetuses underwent a 20-min four-dimensional-ultrasound session. The video recordings for these movements were then imported into in-house software developed to perform kinematic analysis. We found that spatial and temporal characteristics of foetal movements are by no means uncoordinated or unpatterned. By 22 weeks of gestation the movements seem to show the recognizable form of intentional actions, with kinematic patterns that depend on the goal of the action, suggesting a surprisingly advanced level of motor planning.     

Evidence for the early prenatal development of cortical cholinergic afferents from the nucleus of Meynert in the human foetus

A combined histochemical and biochemical approach has shown that the cholinergic system in the nucleus of Meynert region of the substantia innominata is well defined both histochemically and neurochemically within the first 3 months of gestation in the human foetus. Thus, at between 12 and 22 weeks of development the most intense acetylcholinesterase (AChE) histochemical reactivity was observed in the neuropil, cell bodies and processes in the nucleus of Meynert. AChE-stained fibres were observed which coursed from the nucleus of Meynert towards the cortical mantle and within the mantle AChE-stained fibres were also present. Micropunch samples from within the nucleus of Meynert contained higher levels of choline acetyltransferase (ChAT) activity than any other area examined including the striatum, while in the cortical mantle the level of ChAT activity was comparable to that found in the adult cerebral cortex. These observations suggest that the cholinergic innervation from the nucleus of Meynert--considered to be the major source of cholinergic afferents in the adult cerebral cortex--may play a key role in the early development of the human neocortex.     

The study of T-, B-, O- lymphocytes in acute lymphoblastic leukemia.

The T-, B-, and O-lymphocyte count changes were studied during the long-term intensive therapy of 43 ALL children. The control group consisted of 17 healthy children. The T-lymphocytes were identified by spontaneous formation of rosettes with sheep erythrocytes, the B-lymphocytes by EAC-rosette test. Patients were treated according to different program of multiple drug therapy and prophylactic cranial irradiation. During the study the applied therapeutic protocol produced the marked reduction of T- and B- lymphocytes. The decrease of B- lymphocytes was especially pronounced. The preliminary analysis suggests correlation between the reduction of T- and B- lymphocytes and prognosis.     

Non HLA antigenic determinants expressed on activated T and B human lymphocytes

Human antigenic determinants present on activated T and B lymphocytes and not on resting B and T cells defined by serological studies are reported. The reactivity of 13 sera against human PBM activated by various agents was tested using microlymphocytotoxicity technique. Results showed that generally similar reactions are present on B and T blasts whatever the technique of activation (PHA, ConA, PWM, TCGF, EBV and allo activation). Absorption elution studies with 5 sera on 10 alloactivated cells clearly demonstrated their independence from DR determinants. The analysis of results obtained by these 15 sera on blasts from 50 donors showed no correlation with HLA-A, -B, -C, DR and -MB antigens, neither can it be HT (Qa-like) antigens. Furthermore, 5 clusters of sera are reported. The weak correlation coefficients cannot affirm the existence of a system with an allelic distribution although each cell except one out of a panel of 50 individuals carries at most 2 specificities. The segregation of 3 of these specificities within 5 informative families showed no linkage with HLA genes.     

The transfer of human IgG subclasses from mother to foetus

The concentration of IgG subclasses was measured in matched pairs of maternal and cord serum by single radial immunodiffusion. IgG1, IgG3 and IgG4 were present in similar amounts in both the mothers and infants. IgG2 was present in the mothers at about 3 times the amount in the cord blood.     

Immunoglobulin determinants on lymphocytes in germ-free piglets

Surface IgM determinants on splenic lymphocytes were detected in 80-day old pig fetuses using anti-L and anti-μ sera conjugated with horseradish peroxidase. Similarly, by the immunofluorsecence technique, only IgM determinants were demonstrated on unprimed lymphocytes from spleen and bone marrow in fetuses at the end of gestation (on the 112–114th day) and in precolostral, germ-free piglets. The pattern of labeling with anti-μ sera is characteristic for nonactivated lymphocytes as documented on fetal splenic lymphocytes or the small lymphocytes in a dense lymphatic area of the omentum of precolostral piglets. The lymphocytes which showed surface immunofluorescence staining with anti-γ serum were observed in conventionally reared, nonimmunized piglets and appeared in all the germ-free reared piglets which were immunized with sheep red blood cells, human serum albumin or bacterial antigens. We conclude that the true antigen recognition units, or “primary” receptors, on antigen-sensitive uncomitted lymphocytes are exclusively of the IgM type and that the IgG-carrying cells can be detected in piglets only after antigenic stimulation.     

The action of human C3 in soluble or cross-linked form with resting and activated murine B lymphocytes

The third component of complement C3 has been implied in the stimulation of B lymphocytes to proliferation and maturation for Ig secretion. We have reinvestigated the extent of this activation with either activated or resting murine splenic lymphocytes in serum-substituted cultures. Human C3 was used in either soluble or cross-linked form. Soluble as well as Sepharose-bound or glutaraldehyde-cross-linked C3, over a range of concentrations, was inactive with resting splenic lymphocytes of (C57BL/6J X DBA/2)F1, C3H/HeJ and C57BL/6J nu/nu mice. However, lipopolysaccharide-activated spleen cells, enriched for B cell blasts, were stimulated by immobilized and cross-linked C3, while they did not respond to soluble C3. The extent of restimulation was comparable to that induced by lipopolysaccharide and resulted in both increased proliferation and maturation to Ig-secreting cells. The stimulation of the blast cells appears to be C3 specific, since it can be inhibited by free C3.     

The periarteriolar lymphocyte sheath in immunodeficiency T- or B-lymphocyte area?

T- and B-lymphocyte populations in peripheral lymphoid tissues occur in distinct compartments (e.g., the periarteriolar lymphocyte sheath of the splenic white pulp is a T-cell area). The authors report on two patients with severe combined immunodeficiency (SCID) and one patient with immunodeficiency after anti-T-cell treatment for rejection of a heart transplant, in which the area surrounding the central arteriole in spleen white pulp was well-populated despite T-cell deficiency (documented by, for example, severe depletion of lymph node paracortex). Immunologic phenotyping showed the B-lymphoid lineage of lymphocytes at this location. The framework in the periarteriolar area consisted of follicular dendritic cells, which are typical framework components of B-cell areas. We conclude that assessment of only conventional histopathology of the spleen in these patients leads to erroneous conclusions about the type of immunodeficiency and that immunologic phenotyping is required to document the exact nature of the deficiency.     

The secretor status of the foetus

One hundred amniotic fluids were tested for the presence of ABH blood group substances. Gestation at amniocentesis ranged from 12 to 28 weeks, with a mean of 16.6 weeks. The secretor status of the fluid was correlated with the secretor status of the baby after birth as determined from a sample of saliva. Fluid and saliva correlated in 98% of cases. It is felt that contamination with blood is likely to be the main source of error in typing amniotic fluids. However, because of the weaker activity of the anti-H serum, the detection of the presence or absence of H-substance can be doubtful if duplicate tests are not carried out. It is recommended that all fluids be checked for contamination with blood and that duplicate assays be done on two successive occasions. If these precautions are taken, the secretor typing of the amniotic fluid accurately reflects the secretor status of the individual foetus. Though probably not of wide application, the test could be of value in prenatal detection of dystrophia myotonica in individual cases.     

Notch signaling in T- and B-cell development

The Notch family of evolutionarily conserved proteins regulates a broad spectrum of cell-fate decisions and differentiation processes during fetal and post-natal development. The best characterized role of Notch signaling during mammalian hematopoiesis and lymphopoiesis is the essential function of the Notch1 receptor in T-cell lineage commitment. More recent studies have addressed the roles of other Notch receptors and ligands, as well as their downstream targets, revealing additional novel functions of Notch signaling in intra-thymic T-cell development, B-cell development and peripheral T-cell function.     

Triple chromosome synapsis in oocytes from a human foetus with trisomy 21

Oocytes from a human foetus with trisomy 21 were spread using detergent and examined by light and electron microscopy. The three chromosomes 21 occurred as bivalent and univalent or trivalent configurations. In the trivalents the lateral elements of the synaptonemal complex were associated in threes, either completely along the length of the trivalent, or partially, forming a variety of forked structures. This triple association demonstrates that, contrary to the classical view of chromosome pairing, three homologous chromosomes can be held in register at the same site.     

Enzymes involved in phenylalanine metabolism in the human foetus and child

The activities of phenylalanine p-hydroxylase, tyrosine: alpha-ketoglutarate and phenylalanine: pyruvate aminotransferases, and aromatic alpha-ketoacid reductase have been measured in liver biopsies obtained from children with a series of disorders other than phenylketonuria and from human foetuses aged 8.5 to 24 weeks. The importance of such a study in relation to the management of infants with hyperphenylalaninaemia and pregnant phenylketonuric women is discussed     

The development of antigen-binding lymphocytes in foetal tissues

The time of appearance and counts of antigen-binding cells, using radioiodine-labelled flagellin and haemocyanin, was studied in the human and mouse foetus at different gestational ages: the capacity for binding radioiodine-labelled antigens was equated with acquisition of immunological funciton. Cells resembling lymphocytes from human and mouse liver and bone marrow showed antigen binding at early gestational ages, but this binding could not be prevented with species-specific antisera to immunoglobulins. Specific antigen binding to lymphocytes was detected first with thymic lymphocytes, at gestational ages of 12 weeks in humans and 14 days in mice, then with splenic lymphocytes, at 16 weeks in humans and 17 days in mice, and still later with gut lymphocytes. Relative counts of antigen-binding cells in human foetal thymus were maximal at 16–22 weeks and decreased thereafter. Lymphocyte immunocompetence, as judged by the capacity specifically to bind antigen, develops rapidly after the appearance in thymus of cells with the morphology of lymphocytes; this seemed to occur at the equivalent foetal stage in the species studied.     

高压氧对胎兔及新生子兔生长发育的影响

目的:探讨高压氧对妊娠期限以及胎兔、新生子兔生长发育的影响。方法:新西兰妊娠大白兔10只,随机分成实验组A(组)和对照组B(组),实验组接受高压氧治疗,对照组置于常压空气中,连续10天,母兔分娩后,随机选择新生子兔40只,根据母兔接受高压氧与否,按出生体重相近分别配对分为C、D组(即孕兔接受高压氧治疗A组之子兔)和E、F组(即孕兔常压空气对照B组之子兔)。其中C、E组从出生第二天接受HBO治疗,D、F组置于常压空气中。结果:1.A、B两组母兔妊娠期及新生子兔成活率无显著性差异(P>0.05)。2.A、B两组新生子兔平均出生体重无显性差异(P>0.05);C、E两组子兔第12天平均体重及摄乳量与D、F组相比明显增加,有显著性差异(P<0.01);D与F组第12天平均体重及摄乳量无明显显著性差异(P>0.05)。3.各组新生子兔均于第12天开眼。结论:1.高压氧对母兔孕龄无影响,不导致早产。2.小剂量高压氧对正常胎兔生长发育无影响。3.高压氧促进新生子兔生长发育。