A novel dominant-negative PD-1 armored anti-CD19 CAR T cell is safe and effective against refractory/relapsed B cell lymphoma

Refractory/relapsed B cell lymphoma patients who received the available anti-CD19 chimeric antigen receptor (CAR) T cells may still experience a short duration of remission. Here in this study, we evaluated the safety and efficacy of a novel dominant-negative programmed cell death-1 (PD-1) armored anti-CD19 CAR T cells. A total of 9 patients (including 4 diffuse large B cell lymphomas, DLBCL, 2 transformed follicular lymphomas, TFL, and 3 follicular lymphomas, FL) received the novel CAR T cells infusion at a dose of more than 1 × 10⁶/kg. Grade ≥ 3 cytokine release syndrome (CRS) and neurotoxicity were observed in 11.1% (n = 1/9) and 11.1% (n = 1/9) of patients, respectively. The overall response rate (ORR) was 77.8% (n = 7/9) and complete response (CR) rate was 55.6% (n = 5/9). Two patients have ongoing CR (all at 20+ months). CAR T cells expanded after infusion and continued to be detectable at 12+ months in patients with ongoing CR. This novel CD19-CAR T cell was safe and effective with durable remissions in patients with refractory/relapsed B cell lymphoma.     

A soluble recombinant multimeric anti-Rh(D) single-chain Fv/CR1 molecule restores the immune complex binding ability of CR1-deficient erythrocytes

CR1 (CD35, the C3b/C4b receptor) is a widely distributed membrane glycoprotein with a unique cluster conformation on the surface of erythrocytes (E). CR1 on E is responsible for the transport of immune complexes (IC) to liver and spleen. As a cofactor of the C3b cleavage by factor I, CR1 is also a potent inhibitor of C activation and inflammation. In some diseases (systemic lupus erythematosus, hemolytic anemia, AIDS, etc.) an acquired low level of CR1 on E has been observed, leading to an impaired clearance of IC. The aim of this study was to design a heterofunctional molecule that will bind to E and restore a normal or a supranormal CR1 density on E that could mimic the unique distribution pattern of CR1 on normal E. For that purpose a new multimerizing system based on the properties of the C-terminal part of the alpha-chain of the C4 binding protein (C4bp) was used. We first produced a multimeric soluble CR1 that proved to be a better inhibitor of in vitro C activation than the monomeric form of CR1, then a heteromultimeric molecule made of CR1 and single-chain Fv anti-Rh(D) valences able to attach E and providing E with as much as a 10-fold increase in CR1 density with the same CR1 distribution pattern as native E. CR1/single-chain Fv anti-Rh(D)-treated E were able in vitro to attach as many opsonized IC as native E. These data open the way for future use of multimeric and heteromultimeric forms of soluble recombinant CR1 as therapy of IC diseases.     

T Cell Repertoire Diversity Is Decreased in Type 1 Diabetes Patients

Type 1 diabetes mellitus (T1D) is an immune-mediated disease. The autoreactive T cells in T1D patients attack and destroy their own pancreatic cells. In order to systematically investigate the potential autoreactive T cell receptors (TCRs), we used a high-throughput immune repertoire sequencing technique to profile the spectrum of TCRs in individual T1D patients and controls. We sequenced the T cell repertoire of nine T1D patients, four type 2 diabetes (T2D) patients and six nondiabetic controls. The diversity of the T cell repertoire in T1D patients was significantly decreased in comparison with T2D patients (P = 7.0E
08 for CD4+ T cells, P = 1.4E
04 for CD8+ T cells) and nondiabetic controls (P = 2.7E
09 for CD4+ T cells, P = 7.6E
06 for CD8+ T cells). Moreover, T1D patients had significantly more highly-expanded T cell clones than T2D patients (P = 5.2E
06 for CD4+ T cells, P = 1.9E
07 for CD8+ T cells) and nondiabetic controls (P =1.7E
07 for CD4+ T cells, P= 3.3E
03 for CD8+ T cells). Furthermore, we identified a group of highly-expanded T cell receptor clones that are shared by more than two T1D patients. Although further validation in larger cohorts is needed, our data suggest that T cell receptor diversity measurements may become a valuable tool in investigating diabetes, such as using the diversity as an index to distinguish different types of diabetes.     

Anti-CD95 (APO-1/Fas) autoantibodies and T cell depletion in human immunodeficiency virus type 1 (HIV-1)-infected children

Advanced stages of HIV-1-infection are characterized by progressive CD4+ T cell depletion. Peripheral T cells from HIV-1+ donors show accelerated apoptosis in vitro. The CD95 (APO-1/Fas) receptor/ligand system is involved in this process. To further study deregulation of the CD95 system in peripheral T cells during HIV-1-infection, we measured CD95-expression on CD4+ and CD8+ T cells together with serum levels of soluble CD95 (sCD95) and anti-CD95 autoantibodies in HIV-1+ children and healthy controls. Anti-CD95 levels in HIV-1+ children were significantly elevated when compared to uninfected controls, whereas serum levels of sCD95 were not different. In HIV-1+ children, CD95-expression on CD4+ and CD8+ T cells increased with age. A strong correlation between depletion of CD4+ cells in vivo and increase in CD95-expression on CD4+ T cells was observed. In contrast, such a correlation was not found for CD8+ T cells. A negative correlation between anti-CD95 autoantibody levels and CD4+ T cell counts, that was predicted by multiple linear regression analysis of pooled data, was found in individual patients observed longitudinally by repeated measurements. Since anti-CD95 autoantibodies isolated from HIV-infected adults have previously been shown to induce apoptosis of sensitive target cells in vitro, we speculate that the interaction of these antibodies with CD95-positive and CD95-sensitive T cells in vivo might be involved in progressive T cell loss during HIV-1-infection.     

HIV感染者/AIDS病人高迁移率族蛋白1的表达及其临床意义

通过检测74例处于不同病期的HIV感染者/AIDS患者和10例健康对照者PBMCs中HMGB1 mRNA的表达水平及其外周血浆HMGB1、TNF-a和IL-2水平,比较各组之间表达水平的差异及其与CD4＋T淋巴细胞的关系.发现HMGB1 mRNA的表达水平及血浆HMGB1含量在AIDS病人组明显高于感染者组和正常对照组（P〈0.05）;AIDS患者经HAART治疗后疗效差组HMGB1 mRNA的表达水平及血浆HMGB1含量也明显高于疗效好组（P〈0.05）;而经HAART治疗后效果好且免疫功能恢复的患者HMGB1 mRNA的表达及血浆HMGB1含量均较治疗前明显下降（P〈0.05）;当CD4＋T细胞数低于200/μL时,血浆HMGB1含量以及PBMCs中HMGB1 mRNA表达水平与CD4＋T细胞数呈负相关.显示HMGB1在HIV/AIDS发病及病情进展过程中可能起重要作用,HMGB1血浆含量及PBMCs中HMGB1 mRNA的表达水平高低与HIV/AIDS患者病情轻重密切相关.     

Immunologic Control of Mus musculus Papillomavirus Type 1

Persistent papillomas developed in ~10% of out-bred immune-competent SKH-1 mice following MusPV1 challenge of their tail, and in a similar fraction the papillomas were transient, suggesting potential as a model. However, papillomas only occurred in BALB/c or C57BL/6 mice depleted of T cells with anti-CD3 antibody, and they completely regressed within 8 weeks after depletion was stopped. Neither CD4+ nor CD8+ T cell depletion alone in BALB/c or C57BL/6 mice was sufficient to permit visible papilloma formation. However, low levels of MusPV1 were sporadically detected by either genomic DNA-specific PCR analysis of local skin swabs or in situ hybridization of the challenge site with an E6/E7 probe. After switching to CD3+ T cell depletion, papillomas appeared upon 14/15 of mice that had been CD4+ T cell depleted throughout the challenge phase, 1/15 of CD8+ T cell depleted mice, and none in mice without any prior T cell depletion. Both control animals and those depleted with CD8-specific antibody generated MusPV1 L1 capsid-specific antibodies, but not those depleted with CD4-specific antibody prior to T cell depletion with CD3 antibody. Thus, normal BALB/c or C57BL/6 mice eliminate the challenge dose, whereas infection is suppressed but not completely cleared if their CD4 or CD8 T cells are depleted, and recrudescence of MusPV1 is much greater in the former following treatment with CD3 antibody, possibly reflecting their failure to generate capsid antibody. Systemic vaccination of C57BL/6 mice with DNA vectors expressing MusPV1 E6 or E7 fused to calreticulin elicits potent CD8 T cell responses and these immunodominant CD8 T cell epitopes were mapped. Adoptive transfer of a MusPV1 E6-specific CD8+ T cell line controlled established MusPV1 infection and papilloma in RAG1-knockout mice. These findings suggest the potential of immunotherapy for HPV-related disease and the importance of host immunogenetics in the outcome of infection.     

Processing of C3b-opsonized immune complexes bound to non-complement receptor 1 (CR1) sites on red cells: phagocytosis, transfer, and associations with CR1

Severe anemia is a lethal complication of Plasmodium falciparum malaria, particularly in children. Recent studies in children with severe P. falciparum anemia have demonstrated elevated levels of E-bound Abs, reduced E-associated complement receptor 1 (CR1) and decay-accelerating factor (DAF), and pronounced splenic enlargement, suggesting a mechanism for E loss involving Abs, complement, and phagocytosis. Motivated by these reports, we have developed an in vitro model in which human E with Abs and complement bound to CR1, DAF, or glycophorin A are incubated with model human macrophages (the THP-1 cell line). Previous work has demonstrated that immune complex (IC) substrates bound to E CR1, either by an Ab or via C3b, are transferred to macrophages with loss of CR1. In this study, we report that IC bound to DAF or glycophorin A by an Ab linkage are also transferred to macrophages. DAF is lost from the E during the transfer of DAF-bound IC, but the transfer of CR1-bound IC does not lead to a significant loss of DAF. Using glycophorin A-bound IC, we observe competition between transfer of IC and phagocytosis of the E: a fraction (相似文献   

Human T lymphocytes expressing the C3b/C4b complement receptor type one (CR1, CD35) belong to Fc gamma receptor-positive CD4-positive T cells

The phenotypic characteristics of human T lymphocytes expressing the C3b/C4b complement receptor type one (CR1, CD35) were investigated using dual-color surface immunofluorescence and cytofluorometric analysis of stained peripheral blood mononuclear cells (PBMC) from normal individuals. Two to ten percent of PBMC coexpressed CR1 and the CD5, CD2, or CD3 antigen. CR1 was detected on a subset of CD4+ T lymphocytes but not on CD8+ or on Leu-7+ lymphocytes. Costaining for CR1 and for the CD4 subpopulation markers anti-Leu-8, TQ1, OKT17, 2H4, and 4B4 indicated that CR1 on lymphocytes may be coexpressed with any of these phenotypic determinants. All CR1+ lymphocytes expressed Fc gamma receptors (Fc gamma Rs) as assessed by their ability to bind biotinylated dimeric human IgG. The expression of CR1 was increased in mixed lymphocyte reaction with kinetics similar to those of HLA-DR antigen expression. Coexpression of CR1 and Fc gamma R+ may provide a subset of CD4+ lymphocytes with an enhanced ability to bind and respond to C3-bearing complexes of IgG and antigen.     

Distribution and quantitative expression of the complement receptor type 1 (CR1) on human peripheral blood T lymphocytes.

The complement receptor, type 1 (CR1) is expressed on a variety of cell types including primate erythrocytes, phagocytic cells, and B lymphocytes. On these cells, CR1 plays a role in a diverse spectrum of biological activities including the clearance of immune complexes from the circulation, down-regulation of the complement system, recognition of complement-coated microorganisms, and cellular activation. CR1 is also expressed by some, but not all, T lymphocytes. The present study was undertaken in order to examine the distribution of CR1 on normal human T cell subsets by flow cytometry and to quantify the expression of T cell CR1 by radioimmunoassay. Data presented here indicate that, in a panel of 19 normal individuals, a mean of 9.7% of the overall peripheral blood lymphocyte population expressed CR1 and that, as assessed by two-color flow cytometry, 12.0% of CD3+, 13.0% of CD4+, and 20.0% of CD8+ cells expressed CR1. While single peaks of CR1 staining were observed within the CD3 and CD4 subsets, a biphasic pattern of staining was evident within the CD8 subset in which relatively high-intensity CR1 staining was detected within the subpopulation of "dull" CD8+ cells, whereas a lower intensity of CR1 staining was observed within the subpopulation of "bright" CD8+ cells. Duplicate analyses performed over a relatively short time frame suggested that, while the overall percentage of cells that expressed CR1 varied considerably among normal individuals, in at least some individuals the percentage of cells expressing CR1 was relatively stable, especially within the CD4 subset. In cell suspensions enriched for T lymphocytes by rosetting with sheep erythrocytes, 10.0% of the cells were CR1+ and a mean of approximately 3700 CR1 were expressed per CR1+ cell. There was no apparent correlation between the number of CR1 per T cell and the number of CR1 expressed per erythrocyte in the same blood sample. The expression of CR1 on subpopulations within the CD3+, CD4+, and CD8+ lymphocyte subsets may play a role in both normal cell function and in the pathophysiology of disease states including the acquired immune deficiency syndrome (AIDS).     

Anti-tuberculosis (TB) chemotherapy dynamically rescues Th1 and CD8+ T effector levels in Han Chinese pulmonary TB patients

CD4+/CD8+ T cells play a major role in conferring immune protection against tuberculosis (TB), but it remains unknown how the immune responses of CD4+/CD8+ T cells exactly correlate with the clinical variables and disease statuses during anti-TB chemotherapy. To address this, several major immune parameters of CD4+/CD8+ T cells in peripheral blood derived from pulmonary TB patients and healthy volunteers were evaluated. We observed that active TB infection induced lower CD3+ T cell and CD4+ T cell levels but higher CD8+T cell levels, while anti-TB chemotherapy reversed these effects. Also, anti-TB treatment induced enhanced production of IL-2 and IFN-γ but reduced expression of IL-10 and IL-6. Moreover, the dynamic changes of CD3, CD4, and CD8 levels did not show a significant association with sputum smear positivity. However, the frequencies of IL-2+CD4+ or IL-10 + CD4+ T effector subpopulation or IL-1β production in peripheral blood showed significant difference between patients positive for sputum smear and patients negative for sputum smear after anti-TB treatment. These findings implicated that recovery of Th1/CD8+T cell effector levels might be critical immunological events in pulmonary TB patients after treatment and further suggested the importance of these immunological parameters as potential biomarkers for prediction of TB progress and prognosis.     

Cervico-vaginal dysplasia--papillomavirus-induced and HIV-1 infection: role of correlated markers for prognostic evaluation

Sexually-transmitted diseases (STD) can facilitate the progression of HIV-1 infection. Among them, as we have previously demonstrated, cervico-vaginal dysplasia-papillomavirus (HPV)-induced, together with HSV-2 co-infection, seems to be correlated with a more evident immunodepression in HIV-positive women, compared with other sexually transmitted diseases. Here we have analysed some of the main correlated markers of HIV-1 infection progression: CD4 + T lymphocyte concentration, CD4 +/CD8 + T cells ratio, HIV-1 RNA loads and haemoglobin (Hb) concentration in 30 HIV-1 positive women co-infected with HPV, and suffering from cervico-vaginal dysplasia, in different stages. In particular, we noticed a positive correlation, evaluated by Spearman's test, between the degree of progression of dysplastic stages (CIN1 --> 3) until invasive carcinoma (IC) and HIV-1 RNA loads (C(s) = +0.78; p < 0.001), and in contrast, a negative correlation between the same stages of progression and respectively CD4 + T cell concentration (C(s) = -0.54; p = 0.01), ratio (C(s) = - 0.63; p = 0.002) and Hb concentration (C(s) = -0.85; p < 0.001). In conclusion, it is important to underline that low levels of Hb generally paralleled the degree of immunodepression. In fact CD4 + T cell levels and ratio positively correlated with Hb concentrations respectively, with C(s) = + 0.83; p < 0.001 and C(s) = + 0.90; p < 0.001. Finally, the most efficacious antiretroviral combined therapy (HAART = Highly Active Antiretroviral Therapy) can improve the above described laboratory parameters in HIV-1/HPV co-infected women and seems to prevent the progression of CIN1 to the following stages of the dysplastic disease.     

Histamine H1 receptor gene polymorphism acts as a biological indicator of the prediction of therapeutic efficacy in patients with allergic rhinitis in the Chinese Han population

H1-antihistamine has been shown to be effective in treating patients with allergic rhinitis (AR), but its mechanism is still uncertain. We investigated effects of histamine H1 receptor (HRH1) gene polymorphisms on the efficacy of oral H1-antihistamine in perennial patients with AR caused by mites in the Chinese Han population for the first time. A total of 224 Han Chinese patients with AR and 165 Han Chinese healthy volunteers were selected. Genotype and allele frequency distribution of −17C/T in HRH1 gene in patients with AR, serum levels of eosinophil cationic protein (ECP), total immunoglobulin E (IgE), and specific IgE were detected. The clinical symptoms of patients with AR were evaluated with visual analogue scale (VAS). Direct counting method was applied to calculate genotype and allele frequencies. Higher levels of serum ECP and total IgE were shown in the AR group. Moreover, patients with CT, TT, or CT+TT genotype increased the risk of AR incidence in the in the −17C/T site of HRH1, and CC genotype and CT+TT genotype were associated with gender, asthma, VAS score, total IgE level, and specific IgE level in patients with AR. In addition, oral administration of H1-antihistamines improves clinical symptoms of patients with AR. At last, patients with the CC genotype showed the increased efficacy of H1-antihistamines in patients with AR. Our study provides evidence that HRH1 gene polymorphisms may correlate with oral H1-antihistamine efficacy for the treatment of patients with AR, which can be used as a biological indicator of the prediction of therapeutic efficacy of patients with AR.     

Enhancement of HLA class II-restricted CD4+ T cell recognition of human melanoma cells following treatment with bryostatin-1

The majority of melanoma cells express detectable levels of HLA class II proteins, and an increased threshold of cell surface class II is crucial for the stimulation of CD4+ T cells. Bryostatin-1, a protein kinase C (PKC) activator, has been considered as a potent chemotherapeutic agent in a variety of in vitro tumor models. Little is known about the role of bryostatin-1 in HLA class II Ag presentation and immune activation in malignant tumors, especially in melanoma. In this study, we show that bryostatin-1 treatment enhances CD4+ T cell recognition of melanoma cells in the context of HLA class II molecules. We also show that bryostatin-1 treatment of melanoma cells increases class II protein levels by upregulating the class II transactivator (CIITA) gene. Flow cytometry and confocal microscopic analyses revealed that bryostatin-1 treatment upregulated the expression of costimulatory molecules (CD80 and CD86) in melanoma cells, which could prolong the interaction of immune cells and tumors. Bryostatin-1 also induced cellular differentiation in melanoma cells, and reduced tumorigenic factors such as pro-cathepsins and matrix-metalloproteinase-9. These data suggest that bryostatin-1 could be used as a chemo-immunotherapeutic agent for reducing tumorigenic potential of melanoma cells while enhancing CD4+ T cell recognition to prevent tumor recurrence.     

Immune imbalance in the synovial fluid of rheumatoid arthritis patients: effects of intra-articular injection of thymopentin.

T cell subsets in the synovial fluid (SF) and peripheral blood (PB) of RA patients and controls suffering from different forms of chronic synovitis have been investigated. The immunological evaluation showed a reduction of CD4 subsets in RA-SF compared to RA-PB (p less than 0.001), and an almost complete absence of the suppressor-inducer/naive T cells in RA-SF compared to RA-PB and SF from patients with other forms of chronic synovitis. The CD8 subpopulation showed an increased proportion of cytotoxic cells only in RA-SF. On the basis of these results, an intra-articular immunomodulating treatment with thymopentin has been performed: its effects were characterized by an increase of CD8+CD11b+ T cells in the CD8 subset parallel to the enhancement of the suppressor-inducer/naive T cells in the CD4 subset with a statistically significant correlation. The enhanced levels of soluble CD8 decreased after treatment in RA-SF, whereas the soluble IL-2R levels were not significantly modified. Clinical evaluation showed a significative amelioration in all considered parameters.     

Systemic and local characterization of regulatory T cells in a chronic fungal infection in humans

The long-term persistence of pathogens in a host is a hallmark of certain infectious diseases, including schistosomiasis, leishmaniasis, and paracoccidioidomycosis (PCM). Natural regulatory T (Treg) cells are involved in control of the immune responses, including response to pathogens. Because CTLA-4 is constitutively expressed in Treg cells and it acts as a negative regulator of T cell activation in patients with PCM, here we investigated the involvement of Treg cells in the control of systemic and local immune response in patients with PCM. We found that the leukocyte subsets were similar in patients and controls, except for CD11c+CD1a+ cells. However, a higher frequency of CD4+CD25+ T cells expressing CTLA-4, glucorticoid-inducible TNFR, membrane-bound TGF-beta, and forkhead-box 3 were observed in PBMC of patients. In accordance, these cells exhibited stronger suppressive activity when compared with those from controls (94.0 vs 67.5% of inhibition of allogeneic T cell proliferation). In addition, the data showed that CD4+CD25+ T cells expressing CTLA-4+, glucocorticoid-inducible TNFR positive, CD103+, CD45RO+, membrane-bound TGF-beta, forkhead-box 3 positive, and the chemokines receptors CCR4 and CCR5 accumulate in the Paracoccidioides brasiliensis-induced lesions. Indeed, the secreted CCL17 and CCL22, both associated with the migration of Treg cells to peripheral tissues, were also detected in the biopsies. Moreover, the CD4+CD25+ T cell derived from lesions, most of them TGF-beta+, also exhibited functional activity in vitro. Altogether, these data provide the first evidence that Treg cells play a role in controlling local and systemic immune response in patients with a fungal-induced granulomatous disease advancing our understanding about the immune regulation in human chronic diseases.     

The relative importance of CD4+ and CD8+T cells in immunity to pulmonary paracoccidioidomycosis

Protective immunity in paracoccidioidomycosis (PCM) is believed to be mediated by cellular immunity, but the role of T cell subsets has never been investigated. The aim of this study was to characterize the function of CD4+ and CD8+ T cells in the immunity developed by susceptible, intermediate and resistant mice after P. brasiliensis infection. In susceptible mice, depletion of CD4+ T cells did not alter disease severity and anergy of cellular immunity but diminished antibody production. Anti-CD8 treatment led to increased fungal loads, but restored DTH reactivity. In resistant mice, both CD4+ and CD8+ T cells control fungal burdens and cytokines although only the former regulate DTH reactions and antibody production. In the intermediate strain, deficiency of whole T and CD8+ T cells but not of CD4+ T or B cells led to increased mortality rates. Thus, in pulmonary PCM: (a) irrespective of the host susceptibility pattern, fungal loads are mainly controlled by CD8+ T cells, whereas antibody production and DTH reactions are regulated by CD4+ T cells; (c) CD4+ T cells play a protective role in the resistant and intermediate mouse strains, whereas in susceptible mice they are deleted or anergic; (d) genetic resistance to PCM is associated with concomitant CD4+ and CD8+ T cell immunity secreting type 1 and type 2 cytokines.     

Rap1-GTP is a negative regulator of Th cell function and promotes the generation of CD4+CD103+ regulatory T cells in vivo

The small GTPase Rap1 is transiently activated during TCR ligation and regulates integrin-mediated adhesion. To understand the in vivo functions of Rap1 in regulating T cell immune responses, we generated transgenic (Tg) mice, which express the active GTP-bound mutant Rap1E63 in their T lymphocytes. Although Rap1E63-Tg T cells exhibited increased LFA-1-mediated adhesion, ERK1/2 activation and proliferation of Rap1E63-Tg CD4+ T cells were defective. Rap1E63-Tg T cells primed in vivo and restimulated with specific Ag in vitro, exhibited reduced proliferation and produced reduced levels of IL-2. Rap1E63-Tg mice had severely deficient T cell-dependent B cell responses, as determined by impaired Ig class switching. Rap1E63-Tg mice had an increased fraction of CD4+CD103+ regulatory T cells (Treg), which exhibited enhanced suppressive efficiency as compared with CD4+CD103+ Treg from normal littermate control mice. Depletion of CD103+ Treg significantly restored the impaired responses of Rap1E63-Tg CD4+ T cells. Thus Rap1-GTP is a negative regulator of Th cell responses and one mechanism responsible for this effect involves the increase of CD103+ Treg cell fraction. Our results show that Rap1-GTP promotes the generation of CD103+ Treg and may have significant implications in the development of strategies for in vitro generation of Treg for the purpose of novel immunotherapeutic approaches geared toward tolerance induction.     

1α,25-Dihydroxyvitamin D3 inhibits CD40L-induced pro-inflammatory and immunomodulatory activity in Human Monocytes

CD40 ligand (CD40L) stimulation induces proinflammatory and immunomodulatory activity in monocytes. Here, we report on the effects of the steroid hormone 1α,25-dihydroxyvitamin D3 (1,25D3) on human blood monocytes that have been stimulated with the CD40L ligand. Co-treatment of CD40L-stimulated monocytes with 1,25D3 resulted in reduced production and secretion of tumor necrosis factor (TNF)-α and interleukin (IL)-1β, as well as in reduced expression of the surface co-stimulatory molecules CD80 and CD86. In addition, costimulation of CD4+ T lymphocytes by monocytes co-treated with CD40L and 1,25D3 resulted in reduced cell proliferation and diminished interferon (IFN)-γ but enhanced IL-10 production by CD4+ T cells. Finally, 1,25D3 interfered with the ability of CD40L to rescue monocytes from apoptosis induced by serum withdrawal. These findings suggest that 1,25D3 may regulate the interaction of monocytes with T cells or other cell types that express CD40L, thus influencing the outcome of the immune or inflammatory response.     

4-1BB costimulation enhances HSV-1-specific CD8+ T cell responses by the induction of CD11c+CD8+ T cells

Since 4-1BB plays a predominant role in CD8+ T cell responses, we investigated the effects of 4-1BB triggering on the primary and memory CD8+ T responses to HSV-1 infection. 4-1BB was detected on 10-15% of CD4+ and CD8+ T cells following the infection. 4-1BB-positive T cells were in the proliferative mode and showed the enhanced expression of anti-apoptotic proteins. Agonistic anti-4-1BB treatment exerted preferential expansion of CD8+ T cells and gB/H-2Kb-positive CD8+ T cells, and enhanced cytotoxicity against HSV-1 that was mainly mediated by CD11c+CD8+ T cells. CD11c+CD8+ T cells were re-expanded following re-challenge with HSV-1 at post-infection day 50, indicating that CD11c+CD8+ phenotype was maintained in memory CD8+ T cell pool. Our studies demonstrated that 4-1BB stimulation enhanced both primary and memory anti-HSV-1 CD8+ T cell responses, which was mediated by a massive expansion of antigen-specific CD11c+CD8+ T cells.     

sBCMA Plasma Level Dynamics and Anti-BCMA CAR-T-Cell Treatment in Relapsed Multiple Myeloma

BACKGROUND: Novel chimeric antigen receptor T-cells (CAR-T) target the B-cell maturation antigen (BCMA) expressed on multiple myeloma cells. Assays monitoring CAR-T cell expansion and treatment response are being implemented in clinical routine. METHODS: Plasma levels of soluble BCMA (sBCMA) and anti-BCMA CAR-T cell copy numbers were monitored in the blood, following CAR-T cell infusion in patients with relapsed multiple myeloma. sBCMA peptide concentration was determined in the plasma, applying a human BCMA/TNFRS17 ELISA. ddPCR was performed using probes targeting the intracellular signaling domains 4-1BB und CD3zeta of the anti-BCMA CAR-T construct. RESULTS: We report responses in the first five patients who received anti-BCMA CAR- T cell therapy at our center. Four patients achieved a complete remission (CR) in the bone marrow one month after CAR-T infusion, with three patients achieving stringent CR, determined by flow cytometry techniques. Anti-BCMA CAR-T cells were detectable in the peripheral blood for up to 300 days, with copy numbers peaking 7 to 14 days post-infusion. sBCMA plasma levels started declining one to ten days post infusion, reaching minimal levels 30 to 60 days post infusion, before rebounding to normal levels. CONCLUSIONS: Our data confirm a favorable response to treatment in four of the first five patients receiving anti-BCMA CAR-T at our hospital. Anti-BCMA CAR-T cell expansion seems to peak in the peripheral blood in a similar pattern compared to the CAR-T cell products already approved for lymphoma treatment. sBCMA plasma level may be a valid biomarker in assessing response to BCMA-targeting therapies in myeloma patients.