TKI治疗晚期非小细胞肺癌患者免疫功能的变化及意义

目的:通过观察晚期非小细胞肺癌患者TKI治疗前后外周血IgG、IgM、IgA、C3、C4、C-反应蛋白及CD3+、CD4+、CD8+、CD4+/CD8+细胞的表达变化,探讨TKI治疗对晚期非小细胞肺癌患者免疫功能的影响及意义。方法:检测TKI组30例非小细胞肺癌患者TKI治疗前、治疗一个月后外周血IgG、IgM、IgA、C3、C4、C-反应蛋白及CD3+、CD4+、CD8+、CD4+/CD8+细胞表达水平,分析表达变化及与疗效的关系。30例非小细胞肺癌患者作为对照组。结果:治疗前,TKI组与对照组IgG、IgM、IgA、C3、C4、C-反应蛋白水平基本正常,但CD4+细胞数量减低、CD4+/CD8+比值较低、CD8+细胞数量增高,两组相比IgG、IgM、IgA、C3、C4、C-反应蛋白、CD3+、CD4+、CD8+、CD4+/CD8+差异均无统计学意义(P0.05);TKI治疗一个月后,TKI组与对照组IgG、IgM、IgA、C3、C4、C-反应蛋白水平无明显变化,而CD4+细胞数量增多、CD4+/CD8+较前增高,CD8+细胞数量较前减低,两组相比CD3+、IgG、IgM、IgA、C3、C4、C-反应蛋白差异无统计学意义(P0.05),而CD4+、CD4+/CD8+、CD8+差异有统计学意义(P0.01)。结论:TKI治疗后,晚期非小细胞肺癌患者细胞免疫功能得到改善,体现在CD4+、CD8+细胞数量的变化上,且TKI治疗的疗效可通过比较外周血CD4+、CD4+/CD8+、CD8+细胞表达变化体现。     

Local hepatic immune response in rats during primary infection with Fasciola hepatica

The distribution of lymphocyte subpopulations (TCD4+, TCD8+, TCD43+ and Ig+ cells), macrophages and eosinophils were analysed in the inflammatory infiltrates associated with hepatic lesions and in hepatic lymph nodes (HLN) from rats experimentally infected with F. hepatica and necropsied 1, 2, 3, 4, 6 and 8 week post infection (WPI). We also investigated the fixation of immunoglobulin isotypes on migrating flukes in the liver. As early as 1WPI, portal tract areas surrounding migratory tunnels were infiltrated with immune and inflammatory cells. The dominant cells were eosinophils and to lesser extent, macrophages and lymphocytes (TCD4+, TCD8+ and B). Most of the inflammatory and immune cells reached the posterior part of flukes, whereas in front of the parasites these cells were fewer in number. Except for eosinophils, no immune cells penetrated through granuloma consisting of hepatic necrotic cells. As early as 1WPI, IgM could be detected in the liver, and to a lesser extent IgA, IgG2a and IgG2b. At 2WPI, IgE and IgG1 began being detected. IgG2c was detectable at 3WPI. In HLN, we observed numerous microscopic follicles in the cortical zone with proliferation of germinal centres and medullary cords. The protective role of infiltrating cell populations and immunoglobulin isotypes and possible mechanisms of immune evasion by the parasite are discussed.     

Regulatory function for murine intraepithelial lymphocytes. Two subsets of CD3+, T cell receptor-1+ intraepithelial lymphocyte T cells abrogate oral tolerance

The murine intraepithelial lymphocyte (IEL) population is enriched in T cells that express the gamma delta-TCR, however, the biologic function served by these T cells remains obscure. IEL are considered to be major effector cells in mucosal immunity, and we have investigated whether IEL subsets could reverse orally induced systemic unresponsiveness (oral tolerance; OT) and support secondary type responses when adoptively transferred to mice orally tolerized with SRBC. When purified CD3+ IEL from mice orally primed with SRBC were transferred to adoptive hosts and challenged with SRBC, splenic IgM, IgG1, IgG2b, and IgA anti-SRBC plaque-forming cell responses were observed. However, CD3+ IEL from HRBC orally primed mice did not abrogate SRBC induced OT. Further, HRBC-primed CD3+, IEL converted HRBC-specific OT but not SRBC-specific OT. CD3+ IEL could be separated into four subsets based on expression of CD4 and CD8. CD3+, CD4-, 8+ T cells were the major subset (74.5%), with smaller numbers of CD4- and CD8- (double negatives, DN) (7.8%), CD4+, 8- (7.6%) and CD4+, CD8+ (double positives) (10.1%) T cells. Interestingly, both the CD3+, CD8+, and the CD3+, DN IEL subsets abrogated OT, resulting in significant IgM, IgG1, IgG2b, and IgA anti-SRBC plaque-forming cell responses when adoptively transferred to mice with OT. However, neither CD3+, CD4+, CD8-, nor double positive T cells affected OT when studied in this system. The CD3+, CD8+ IEL subset could be further separated into Thy-1+ (16.6%) and Thy-1- (83.4%) cells; adoptive transfer of Thy-1- cells abrogated oral tolerance whereas the Thy-1+ subset was without effect. When the expression of TCR on IEL with this biologic function was determined by use of monoclonal anti-alpha beta TCR (H57.597), TCR2-, CD3+ IEL possessed immunoregulatory function whereas the alpha beta-TCR+ (TCR2+) fraction did not abrogate OT. Immunoprecipitation of membrane fractions obtained from purified CD3+, CD4-, CD8+, Thy-1- IEL with polyclonal anti-delta peptide (Tyr-Ala-Asn-Ser-Phe-Asn-Asn-Glu-Lys-Leu) antibody revealed bands of 45 and 35 kDa, corresponding to the delta- and gamma-chains, respectively. These results suggest that gamma delta-TCR+ IEL possess a regulatory function, namely the restoration of immune responses in a state of oral tolerance. Further, both CD3+, CD4-, CD8+, Thy-1-, and CD3+, DN IEL T cells exhibit this effector contrasuppressor function.     

Development and distribution of B lineage cells in the domestic cat: analysis with monoclonal antibodies to cat mu-, gamma-, kappa-, and lambda-chains and heterologous anti-alpha antibodies

To trace the development and distribution of B lineage cells in the domestic cat (Felis catus), we have produced monoclonal antibodies against mu-, gamma-, kappa-, and lambda-chains of feline immunoglobulins (Ig). Goat antibodies against human mu-, alpha-, and lambda-chains, which are reactive with shared determinants on their feline counterparts, were used in conjunction with the panel of mouse monoclonal antibodies. Cytoplasmic mu+ pre-B cells and surface IgM+ B lymphocytes were observed in 42 day fetal liver in which pre-B cells were more abundant than IgM+ B cells. Pre-B cells also were found in bone marrow in young cats, and continued to be generated in the marrow throughout life. In the spleen, adult levels of B cells were attained by 12 wk of age, at which time the frequencies of surface IgM+, IgG+, and lambda+ cells were 49, 3, and 40%, respectively. The distributions of Ig isotypes also were determined among plasma cells as a function of age and tissue localization. IgM plasma cells were predominant in the bone marrow of 1-wk-old cats, whereas IgG plasma cells were the prevalent isotype in adult bone marrow. In the mesenteric lymph nodes of adult animals, the frequency distributions of IgM, IgG, and IgA plasma cells were similar to the frequency distributions of IgM, IgG, and IgA isotypes among bone marrow plasma cells. IgA+ plasma cells predominated in the intestinal lamina propria, in which IgG+ and IgM+ plasma cells were relatively infrequent. In the tissues of both young and adult animals, the ratio of lambda:kappa expression was approximately 3:1. We conclude that the pattern of B cell development in the cat resembles that found in other mammals, except that the kappa to lambda ratio is reversed.     

TKI治疗晚期tPd,细胞肺癌患者免疫功能的变化及意义

目的：通过观察晚期非小细胞肺癌患者TKI治疗前后外周血IgG、[gM、IgA、C3、c4、C-反应蛋白及CD3＋、CD4＋、CD8＋、CD4＋／CD8＋细胞的表达变化,探讨TKI治疗对晚期非小细胞肺癌患者免疫功能的影响及意义。方法：检测TKI组30例非小细胞肺癌患者TKI治疗前、治疗一个月后外周血IgG、IgM、IgA、C3、C4、C-反应蛋白及CD3＋、CD4＋,CD8＋、CD4＋／CD8＋细胞表达水平,分析表达变化及与疗效的关系。30例非小细胞肺癌患者作为对照组。结果：治疗前,TKI组与对照组IgG、IgM、IgA、C3、C4、c＋反应蛋白水平基本正常,但CD4＋细胞数量减低、CD4＋／CD8＋比值较低、CD8＋细胞数量增高,两组相比IgG、IgM、IgA、C3、C4、C-反应蛋白、CD3＋、CD4＋．CD8＋、CD4＋／CD8‘差异均无统计学意义（P〉0．05）;TKI治疗一个月后,TKI组与对照组IgG、IgM、IgA、C3、C4、C-反应蛋白水平无明显变化,而CD4＋细胞数量增多、CD4＋／CD8＋较前增高,CD8＋细胞数量较前减低,两组相比CD3＋、IgG、IgM、IgA、C3、C4、c-反应蛋白差异无统计学意义（P〉0．05）,而CD4＋．CD4＋／CD8＋、CD8＋差异有统计学意义（P〈O．01）。结论：TKI治疗后,晚期非小细胞肺癌患者细胞免疫功能得到改善,体现在CD4＋,CD8＋细胞数量的变化上,且TKI治疗的疗效可通过比较外周血CD4＋、CD4＋／CD8＋、cD8＋细胞表达变化体现。     

Anaphylactic properties of mouse monoclonal IgG2a antibodies

Mouse monoclonal antibodies (10 hybridoma antibodies specific for soluble antigens, 8 hybridoma antibodies specific for H-2 $\text{K}\text{D}$ antigens, and 9 myeloma immunoglobulins, among which 5 had a known specificity) of the IgG1, IgG2a, IgG2b, IgG3, IgA, and IgM isotypes were studied for their ability to induce mouse mast cell degranulation in vitro, in the presence of specific antigen or after heat aggregation. Monoclonal IgG1 antibodies, as well as IgG2b, IgG3, IgA, and IgM behaved as polyclonal antibodies of corresponding classes: all IgG1 induced mast cell degranulation with typical characteristics of IgG-mediated anaphylactic reactions, whereas IgG2b, IgG3, IgA, and IgM did not. By contrast, 2 hybridoma IgG2a and 3 myeloma IgG2a induced intense mast cell degranulation that could not be explained by a contamination with IgG1 or IgG1-IgG2a hybrid molecules. IgG2a-mediated reactions were observed in four different situations: soluble antigen-hybridoma IgG2a complexes, specific H-2 antigen-bearing mast cells challenged with hybridoma IgG2a anti-H-2, heat-aggregated myeloma IgG2a, and soluble antigen-myeloma IgG2a complexes. The conclusion was reached that mouse mast cells could be activated by mouse monoclonal IgG2a antibodies through a noncytotoxic, complement-independent mechanism involving mast cell Fcγ receptors.     

Characterization of Nippostrongylus brasiliensis infection in different strains of mice

Five mouse strains, CBA/J, BALB/c, C3H/HeJ, A/J, and C57Bl/6J-bg-bg, all showed similar expulsion kinetics for Nippostrongylus brasiliensis (infective dose = 500 L3). Typically, parasite recovery was maximal on day 2 in the lungs and by day 4 in the small intestine. Few worms (less than 5% infective dose) were recovered on day 14 in all strains. These same mouse strains exhibited immune depression on day 5 of infection with mesenteric lymph node cells (MLN) showing reduced (10-30% normal) IgM, IgG, and IgA responses against heterologous antigen. The intestinal mast cell numbers and tissue histamine levels were examined in CBA/J mice. Mast cell numbers increased (normal = less than 1/villous crypt unit; VCU) from day 5 and peaked on day 12 (greater than 15/VCU). Intestinal histamine levels did not completely correlate with mast cell numbers with maximum concentrations (240 +/- 73 ng/g, 2-fold over normal) reached by day 8. Histamine concentrations in the intestine returned to normal levels by day 20.     

In vivo role of lymphocyte subpopulations in the control of virus excretion and mucosal antibody responses of cattle infected with rotavirus.

T-cell control of primary rotavirus infection and mucosal antibody responses to rotavirus was studied with monoclonal antibodies (MAb) to deplete gnotobiotic calves of CD4+, CD8+, BoWC1+, or both CD4+ and CD8+ lymphocytes prior to infection with rotavirus. Injection of these MAb produced specific reductions in circulating and tissue lymphocyte subpopulations. Following infection, control calves developed fecal immunoglobulin M (IgM) and IgA antibodies and serum IgM and IgG1 antibodies; there was no IgG2 antibody produced. Anti-CD4-treated calves had reduced fecal and serum antibody responses to rotavirus compared with control calves. The IgM response was less affected than the other isotypes. Calves concurrently injected with MAb to CD4 and CD8 had antibody responses similar to those of calves injected with anti-CD4 antibody alone. No effect on serum or fecal antibody levels was seen when MAb to CD8 or BoWC1 were injected alone. Virus excretion was significantly increased in calves depleted of CD8+ cells. Depletion of CD4+ cells or BoWC1+ cells had no effect on virus excretion. Calves depleted of both CD4+ and CD8+ cells excreted amounts of virus similar to those of calves depleted of CD8+ cells alone. Onset and duration of virus excretion were not affected by any of the MAb treatments. We conclude that a CD8+ cell population is involved in limiting primary rotavirus infection, while CD4+ or BoWC1+ (gamma/delta+ TcR) lymphocytes are not. Furthermore, CD4+ lymphocytes (but not CD8+ or BoWC1+ lymphocytes) were shown to be important in the generation of mucosal, as well as systemic, antibody responses.     

肠内增强免疫营养对重症肺炎患者免疫功能及 预后的影响

目的探讨肠内增强免疫营养对重症肺炎患者免疫功能及预后的影响并分析疗效。方法选择2016年3月至2017年12月我院收治的100例重症肺炎患者,依据抽签法分为两组,其中研究组50例,常规组50例。研究组患者在常规治疗基础上给予免疫增强型肠内营养制剂,对照组患者在常规治疗基础上给予普通肠内营养制剂。比较两组患者干预后粪便菌群变化,干预前后免疫功能和凝血功能的变化,并记录两组患者干预后的并发症发生率和死亡人数。结果研究组患者菌群失调发生率为4.00%(2/50),低于常规组的20.00%(10/50)(P0.05)。干预前,两组患者免疫功能和凝血功能水平差异无统计学意义(P0.05)。干预治疗1周和2周后,两组患者CD_3~+细胞、CD_4~+细胞、CD_4~+/CD_8~+、IgA、IgM和IgG水平均上升,CD_8~+细胞、FIB和D-二聚体水平均降低,且研究组CD_3~+细胞、CD_4~+细胞、CD_4~+/CD_8~+、IgA、IgM和IgG水平均高于常规组,CD_8~+、FIB和D-二聚体水平均低于常规组(P0.05)。研究组患者并发症总发生率为10.00%(5/50),低于常规组(P0.05)。对照组有1例死亡,研究组未出现死亡。结论肠内免疫增强营养支持可提高患者疗效,改善患者免疫功能和凝血功能,减少并发症发生,提高患者预后。     

阿莫西林联合甲强龙治疗老年支气管肺炎患者的临床效果及机制分析

目的：探讨阿莫西林联合甲强龙治疗老年支气管肺炎患者的临床效果及其可能的作用机制。方法：选取我院呼吸科收治的 老年支气管肺炎患者84例,根据治疗方案不同分为常规组及试验组。比较两组患者治疗前后临床体征、IgA、IgM、IgG、CD4+及 CD8+T 淋巴细胞、NK 细胞及血清LDH3、LDH4、HBDH水平的变化情况。结果：治疗后,试验组咳喘、高热、肺内干湿罗音的恢复 时间明显短于常规组,IgA、IgM、IgG、LDH、HBDH、NK 细胞及CD8+T 淋巴细胞水平明显低于常规组,CD4+T 淋巴细胞水平明显 高于常规组,差异均具有统计学意义(P<0.05)。结论：阿莫西林联合甲强龙可有效快速改善老年支气管肺炎患者的临床症状,这可 能与其降低IgA、IgM、IgG、LDH、HBDHNK 细胞及CD8+T 淋巴细胞水平及提高CD4+T 淋巴细胞水平有关。     

The asymmetry in idiotype-isotype expression in the response to phosphocholine is due to divergence in the expressed repertoires of Lyb-5+ and Lyb-5- B cells

The X-linked CBA/N immune defect was used to investigate the roles of Lyb-5- and Lyb-5+ B cells in the memory response to PC-KLH (phosphocholine-conjugated keyhole limpet hemocyanin). (CBA/N X BALB/c)F1 (CB) male mice express the xid mutation and thereby lack the Lyb-5+ B cell subset, whereas their female littermates are normal and express both Lyb-5+ and Lyb-5- B cells. After priming with PC-conjugated hemocyanin (PC-Hy) in complete Freund's adjuvant, female B cells produce three phenotypic sets of PC-KLH-specific antibody. The first set (group I) is dominated by T15+, IgM, IgA, and IgG3, PC-specific antibodies. The second subset (group II) is specific for phenylphosphocholine (PPC), and is dominated by T15-, IgG1, and IgG2 antibodies. The third set (group III) recognizes an epitope(s) composed of both the PPC hapten and carrier determinants. PC-Hy-primed B cells from immune defective CB male mice produce the same number of IgG1 and IgG2 plaque-forming cells (PFC) as do PC-Hy-primed normal female cells, and these PFC are also predominantly T15- and PPC specific (group II). In addition, a significant amount of group III IgG1 and IgG2 antibody is observed in the immune defective male response. In contrast to female B cells, immune defective male B cells produce a low IgM, IgA, and IgG3 memory response that is not composed of PC-specific (group I) antibodies; in fact, most of these antibodies arise from group III precursors and are not inhibited by either PC or PPC. PC-specific antibodies usually represent less than 25% of the anti-PC-KLH response in immune defective mice; however, these PC-specific antibodies are predominantly T15-. These data suggest that the Lyb-5-B cells in both normal and immune defective mice produce the T15-, IgG1, and IgG2 antibodies that dominate the secondary immune response to PC-KLH, and that the Lyb-5+ B cells produce the T15+, IgM, IgA, and IgG3 portion of the secondary response in normal mice. This hypothesis was confirmed by priming normal mice with the R36a strain of Streptococcus pneumoniae or with PC-Hy in saline. These forms of PC-antigen prime only the Lyb-5+ B cell subset. The adoptive transfer of these two B cell sources results in an anti-PC-KLH response that is T15 dominant and totally PC inhibitable.(ABSTRACT TRUNCATED AT 400 WORDS)     

Characterization of the interaction of human eosinophils and neutrophils with opsonized particles

The interaction of human eosinophils with opsonized particles was compared with that of human neutrophils. When eosinophils are stimulated with serum-opsonized zymosan particles, the lag time in H2O2 production is twice as long as found with neutrophils. Moreover, the concentration of these IgG + C3-coated particles required for optimal stimulation is about four times as high for eosinophils as for neutrophils. Under these conditions, the two cell types generate similar amounts of H2O2. However, eosinophils produce twice as much H2O2 as do neutrophils when stimulated with the soluble agent phorbol myristate acetate. Thus, although the oxidase capacity of eosinophils is larger than that of neutrophils, opsonized zymosan is a weak trigger for this activity in eosinophils. This phenomenon may be due to differences between the two cell types in the plasma membrane receptors or in the receptor oxidase transducing signal. The following are indications for the first possibility. i) IgG interacts poorly with the Fc gamma receptors on the eosinophil surface compared with those on neutrophils. This was shown by the inability of IgG-coated zymosan or IgG-coated latex to trigger any substantial H2O2 production by eosinophils unless brought into close contact with these cells by centrifugation. In contrast, neutrophils are stimulated by these particles both in suspension and in a pellet. The dissimilarity of the Fc gamma receptors on eosinophils and neutrophils was also shown with respect to antigenicity, determined by the monoclonal antibodies 3G8 and CLB-FcR-1. ii) Eosinophils contain about half as many receptors for C3b and C3bi on their surface as do neutrophils, also detected with monoclonal antibodies. The interaction of IgG subclasses with functional Fc gamma receptors on eosinophils and neutrophils showed that eosinophils release twice as much H2O2 as do neutrophils upon interaction with IgG1-, IgG2-, or IgG3-coated Sepharose beads, but this difference becomes fivefold with IgG4-coated Sepharose. This might be of relevance to the situation of chronic antigenic stimulation, e.g., in chronic schistosomiasis, in which eosinophil numbers and IgG4 antibody levels are elevated.     

Characterization of the immunodeficiency of RIIS/J [corrected] mice. I. Association with the CD5 (LY-1) [corrected] B cell lineage

RIIIS/J mice produce low antibody responses to several polysaccharide Ag of bacterial origin. They have low levels of serum IgM and IgG3 and high levels of serum IgG2a and IgG2b. Low serum IgM and IgG3 have been attributed to a low frequency of CD5 (Ly-1) B cells, which play an important role in the production of natural antibodies. Indeed, RIIIS/J mice have a low frequency of CD5 (Ly-1)+, IgM bright+, Ly-5 (B220)dull+ (i.e., CD5 (Ly-1) B) cells in their peritoneum. RIIIS/J mice treated with LPS produce a low anti-bromelain-treated mouse RBC splenic plaque-forming cell response and a normal anti-mouse transferrin splenic PFC response. Those data are compatible with the fact that CD5 (Ly-1) B cells contain the precursors of B lymphocytes secreting anti-bromelain-treated mouse RBC antibody. However, they have a higher frequency of IgM bright+, Mac-1+ cells in their peritoneum. These cells represent the CD5 (Ly-1) "sister population" of CD5 (Ly-1) B cells described by others. This suggests that characteristics usually associated with the CD5 (Ly-1) lineage are applicable only to the CD5 (Ly-1)+ Mac-1+ IgM+ population, but not the related CD5 (Ly-1)- Mac-1+ IgM+ population. RIIIS/J mice should thus prove a valuable model to study the CD5 (Ly-1) B cell lineage.     

Regulation of T15 idiotype dominance. II. Genes unlinked to the Igh locus regulate T15 dominance of the secondary adoptive transfer response to phosphocholine

We have studied the idiotype and fine specificity of the secondary immune response to phosphocholine (PC) in C57BL (B10, B10.D2, and B.C8) and BALB (BALB/c, BAB-14, and C.B20) congenic strains of mice. In vivo IgM responses of mice from these two genetic backgrounds differed in their T15 idiotypic representation. BALB strains expressed the T15 idiotype on greater than 90% of their IgM, PC-specific plaque-forming cells (PFC), whereas C57BL strains expressed the T15 idiotype on approximately 50% of their IgM PFC. All strains examined expressed greater than 75% PC-inhibitable, VHPC idiotype-positive, IgM PFC. The IgG3 and IgA memory responses were similar to the IgM memory response; BALB strains produced a higher proportion of T15+ PFC than C57BL strains; however, the majority of IgG3 and IgA PFC in all strains were VHPC+, and PC-inhibitable. In contrast, the IgG1 memory response was not dominated by T15+, VHPC+, PC-inhibitable PFC in any of the strains tested. The IgG1 PFC required nitrophenylphosphocholine (NPPC) for efficient inhibition. The IgG2 memory response generally mimicked the IgG1 response with respect to idiotype and specificity. These data demonstrate that the representation of the T15 idiotype in the anti-PC immune response is determined by genes outside both the MHC and Igh genetic loci. Control of T15 expression in secondary IgM, IgG3, and IgA anti-PC responses was examined by using a cell-mixing protocol with primed T and B cells from BALB/c and B10.D2 mice. T15 representation in these responses was determined by the genotype of the B cell, not by the genotype of the helper T cell. Similarly, the B cell genotype was responsible for the idiotypic profile of a primary, in vitro, T-dependent, anti-PC response.     

Immune status and proinflammatury cytokines in pregnant women with acute cytomegalovirus infection

A total of 64 pregnant women aged 16-40 years with acute cytomegalovirus (CMV) infection were examined. CMV infection was diagnosed by the detection of anti- CMV IgM (by the enzyme immunoassay) or DNA by PCR in the blood. The immunophenotype of lymphocytes CD3+, CD4+, CD8+, CD16+, CD19+, IgG, IgM, IgA and the spontaneous production of TNFalpha and IL-8 in the blood were studied. In pregnant women with CMV infection the presence of the immunosuppression of cell-mediated immunity reactions, the hyperproduction of Fc-receptors of natural killers, B lymphocytes (CD19+), the hyperglobulinemia of serum IgM and IgG, as well as the increased synthesis of proinflammatory cytokines--TNFalpha and IL-8--were established.     

Effects of tobacco glycoprotein (TGP) on the immune system. II. TGP stimulates the proliferation of human T cells and the differentiation of human B cells into Ig secreting cells

We have been studying the effects of tobacco glycoprotein (TGP), a polyphenol-rich glycoprotein isolated from cured tobacco leaves, on the immune system. We have shown previously that mice immunized with TGP produce preferentially antibodies of the IgE isotype and that TGP is a T cell-independent B cell mitogen for mice, which stimulates B cell proliferation and B cell differentiation into Ig-secreting cells. We report herein that TGP stimulates a significant increase in [3H]TdR incorporation by human PBL and by human cord blood lymphocytes. The magnitude of the proliferative response of PBL to TGP does not correlate with the donor's titer of IgE antibodies to TGP, as assayed by a wheal and flare response after an i.d. injection of TGP, neither does it correlate with the donor's smoking history. [3H]TdR uptake is not observed before day 5 of culture, and the response peaks between days 5 and 10 of culture. Analysis of the cellular basis for the proliferative response suggests that T cells are proliferating. Two-parameter analysis by flow cytometry shows that CD3+, CD4+, and CD8+ cells are in the S + G2 + M phases, but not Ig-bearing cells or monocytes. A significant increase in HLA-DR (Ia)-bearing cells is observed on cells in all of the cell cycle phases. This increase coincides with cells entering the S phase. No increase is observed in the expression of the IL-2-R as assayed by the anti-Tac antibody. TGP also stimulates human PBL to differentiate and to produce Ig of the IgM, IgG, and IgA isotypes, without stimulating a detectable B cell proliferative response. The proliferative response of PBL is clearly due to TGP and not to contamination with LPS, because by the limulus amebocyte assay the TGP preparation contains less than 2% LPS, which could not account for the stimulation observed.     

Hymenolepis citelli, H. diminuta and H. microstoma: immunoglobulin-containing cells in the lamina propria of the mouse gut during primary and secondary infections

The indirect immunofluorescent technique was used to determine the occurrence of IgA, IgM and IgG1 immunoglobulin-containing cells in local intestinal mucosal immune responses to Hymenolepis citelli, H. diminuta and H. microstoma infections in mice. In the intestinal lamina propria of H. citelli and H. diminuta infected mice there was no increase in the mean numbers of immunoglobulin-containing cells when compared with uninfected control mice, but there was in H. microstoma infected mice. The numbers of IgG1- positive cells in both infected and uninfected mice were very small relative to IgA and IgM immunocytes. The distribution of immunocytes in the lamina propria of infected and uninfected mice was essentially similar and the localization of isotypes in duodenal sections showed no immunoglobulins in the villous epithelial cells. There was also no marked difference between primary and secondary infections indicating that immunoglobulin-containing cells play no major role in functional immunity against hymenolepid infections in the mouse. The presence of IgA and IgM was also demonstrated on the tegument of the tapeworms, although the distribution was patchy and more abundant on H. microstoma than on H. diminuta or H. citelli. The time of appearance of both isotypes was latest on H. citelli.     

Role of T-lymphocyte subsets in recovery from respiratory syncytial virus infection in calves.

The role of T-cell subsets in respiratory syncytial virus (RSV) infection was investigated by using monoclonal antibodies (MAbs) to selectively deplete gnotobiotic calves of CD4+, CD8+, or WC1+ gamma delta T-cell receptor+ lymphocytes. Injection of these MAbs produced specific reductions of the target cell populations in the circulation and tissues. Ten days after RSV infection, immunoglobulin M (IgM), IgG1, and IgA antibodies were detected in sera and lung washings from control calves. Depletion of CD8+ T cells had no effect on either the serum or local antibody responses to RSV, whereas depletion of CD4+ T cells suppressed the antibody responses in two of three calves. The IgM and IgA responses were significantly increased in the lung washings of calves from which WC1+ T cells were depleted. Depletion of CD4+ or WC1+ T cells caused no significant delay in virus clearance, although an increase in the extent of pneumonic consolidation was observed in anti-CD4-treated calves. Nasopharyngeal excretion of RSV was prolonged in calves depleted of CD8+ T cells, and virus was isolated in high titers from lung washings of these animals 10 days after infection, whereas virus had been cleared from lung washings of all other animals. The delayed virus clearance was associated with an increase in the severity of pneumonic consolidation in three of four of the calves from which CD8+ T cells were depleted. This study shows that CD8+ T cells play a dominant role in the recovery of calves from RSV infection.     

Selective adherence of IgA to murine Peyer's patch M cells: evidence for a novel IgA receptor

M cells represent the primary route by which mucosal Ags are transported across the intestinal epithelium and delivered to underlying gut-associated lymphoid tissues. In rodents and rabbits, Peyer's patch M cells selectively bind and endocytose secretory IgA (SIgA) Abs. Neither the nature of the M cell IgR nor the domains of SIgA involved in this interaction are known. Using a mouse ligated ileal loop assay, we found that monoclonal IgA Abs with or without secretory component, but not IgG or IgM Abs, bound to the apical surfaces of Peyer's patch M cells, indicating that the receptor is specific for the IgA isotype. Human serum IgA and colostral SIgA also bound to mouse M cells. The asialoglycoprotein receptor or other lectin-like receptors were not detected on the apical surfaces of M cells. We used recombinant human IgA1 and human IgA2 Abs and domain swapped IgA/IgG chimeras to determine that both domains Calpha1 and Calpha2 are required for IgA adherence to mouse Peyer's patch M cells. This distinguishes the M cell IgA receptor from CD89 (FcalphaI), which binds domains Calpha2-Calpha3. Finally, we observed by immunofluorescence microscopy that some M cells in the human ileum are coated with IgA. Together these data suggest that mouse, and possibly human, M cells express an IgA-specific receptor on their apical surfaces that mediates the transepithelial transport of SIgA from the intestinal lumen to underlying gut-associated organized lymphoid tissues.     

B1 B cell numbers and antibodies against phosphorylcholine and LPS are increased in IL-6 gene knockout mice

Peritoneal cavity cells were isolated from IL6-gene knockout (IL6(-/-)) and wild-type mice and stained for expression of IgM, CD5, and CD23. B1 cell (IgM(+)/CD23(-), CD5(+)/IgM(+)) numbers were increased twofold in IL6(-/-) mice compared to normals while IgM(+)/CD23(+) (B2) cell numbers were reduced threefold. Intestinal antibody levels were also determined for both total immunoglobulin and phosphorylcholine (PC)-specific and LPS-specific antibody following oral challenge with attenuated Salmonella typhimurium. Total immunoglobulin levels (IgM, IgG, and IgA) were reduced 60-80% in intestinal secretions of IL6(-/-) mice compared to wild-type controls; however, PC-specific antibody was significantly higher in IL6(-/-) mice. Anti-LPS antibodies were also three- to sevenfold higher in IL6(-/-) mice compared to controls following Salmonella challenge. These data suggest that in IL6(-/-) mice the development of mucosal B2 cells is impaired but that intestinal B1 cells responding to microbial antigens such as PC and LPS develop normally and are fully functional.