Numbers Of Lymphocyte Subsets Research Articles

Comparative flow immunophenotypic features of the inflammatory infiltrates of Hodgkin lymphoma and lymphoid hyperplasia

Hodgkin lymphoma (HL) is characterized by relatively few malignant Reed-Sternberg (RS) cells admixed within a reactive T cell rich inflammatory infiltrate. There is growing recognition that the HL-associated inflammatory milieu may enhance rather than inhibit growth of RS tumor cells. Since little is known of the immunophenotype of the HL inflammatory infiltrate we have performed a detailed retrospective comparison of the flow immunophenotype of HL and reactive lymphoid hyperplasia (RLH) to identify HL-specific immunophenotypic features. Single cell suspensions from 59 lymph nodes involved by HL (at initial diagnosis) and 38 lymph nodes involved by RLH were subjected to a battery of 3-color combinations of well-characterized fluorochrome-conjugated monoclonal antibodies (DAKO) to a number of lymphocyte subsets. Cells were analyzed on a FACSCalibur flow cytometer with CellQuest software (Becton Dickinson). Overall, CD4+ T cells are increased and CD19+ B cells decreased in HL vs. RLH, yielding median T:B cell (CD3:CD20) ratios of 2.3:1 and 1.6:1, resp. There is no difference in median CD8+ T cell % (16% in HL & RLH). The T:B cell ratio is highest in nodular sclerosis (NSHL) and lymphocyte depletion (LDHL) subtypes, and lowest in mixed cellularity HL (MCHL). There is no significant difference in CD4:CD8 ratio in any comparison. NKT cells were slightly increased in HL vs. RLH, especially in MCHL. CD4+CD25+ regulatory T cells are significantly increased in HL (9%) vs. RLH (2%), especially in MCHL (29%) and NSHL (12%). EBV positivity in NSHL is associated with older age, decreased CD4+CD25+ regulatory T cells, CD4:CD8 ratio, and CD19/CD20+ B cells, and increased NKT cells, and CD14+ low forward-side scatter-gated monocytes. The cellular composition of the reactive lymphocytic infiltrate in HL differs significantly from that seen in RLH, with significant differences also noted between HL subtypes. In general, the HL infiltrate contains increased T cells (CD4+ and NKT subsets), decreased B cells, and increased regulatory T cells in comparison with RLH. The major difference between HL subtypes is decreased CD4+ T cells in MCHL as compared with NSHL and NLPHL. The most notable EBV-related difference in NSHL is increased regulatory T cells in EBV negative cases. While many differences in the reactive lymphocytic infiltrate of Hodgkin lymphoma and reactive lymphoid hyperplasia were identified, the sole difference that may prove to be of differential diagnostic value in flow cytometric analysis of HL versus RLH is the increased percentage of CD4+ bright CD25+ regulatory T cells in HL.

Although Macrophage-Tropic Simian/Human Immunodeficiency Viruses Can Exhibit a Range of Pathogenic Phenotypes, a Majority of Isolates Induce No Clinical Disease in Immunocompetent Macaques

Unlike prototypical lentiviruses like visna and caprine arthritis-encephalitis viruses, which are mainly macrophage tropic (M-tropic), primate lentiviruses primarily target CD4+ T lymphocytes. We previously reported that during the late phase of highly pathogenic chimeric simian/human immunodeficiency virus (SHIV) infections of rhesus macaques, when CD4+ T cells have been systemically eliminated, high levels of viremia are maintained from productively infected macrophages. The availability of several different M-tropic SHIVs from such late-stage immunocompromised animals provided the opportunity to assess whether they might contribute to the immune deficiency induced by their T-cell-tropic parental viruses or possibly cause a distinct disease based on their capacity to infect macrophages. Pairs of rhesus monkeys were therefore inoculated intravenously with six different M-tropic SHIV preparations, and their plasma viral RNA loads, circulating lymphocyte subset numbers, and eventual disease outcomes were monitored. Only one of these six M-tropic SHIVs induced any disease; the disease phenotype observed was the typical rapid, complete, and irreversible depletion of CD4+ T cells induced by pathogenic SHIVs. An analysis of two asymptomatic monkeys, previously inoculated with an M-tropic SHIV recovered directly from alveolar macrophages, revealed that this inoculum targeted alveolar macrophages in vivo, compared to a T-cell-tropic virus, yet no clinical disease occurred. Although one isolate did, in fact, induce the prototypical rapid, irreversible, and complete loss of CD4+ T cells, indicating that M-tropism and pathogenicity may not be inversely related, the majority of M-tropic SHIVs induced no clinical disease in immunocompetent macaques.

The importance of T-lymphocyte subsets on overall survival of colorectal and gastric cancer patients

The aim of this study was to evaluate the influence of cellular immunity parameters on overall survival of colorectal and gastric cancer patients after surgery. The parameters of cellular immunity (CD3+, CD4+, CD8+, CD20+, and CD16+) were determined by immunofluorescence method. Cox regression analysis showed no impact of the estimated preoperative and postoperative parameters of cellular immunity on overall survival of colorectal cancer patients and similarly of gastric cancer patients in stage II. However, the analysis showed that the survival of colorectal and gastric cancer patients in stage III depended on immunological parameters determined before surgery: CD3+ (P=0.007 and P=0.007, respectively), CD4+ (P=0.021 and P=0.011, respectively), and CD8+ (P=0.047 and P=0.007) counts. Only the survival of colorectal cancer patients depended on natural killer cell number (P=0.009). Kaplan-Meier analysis showed that patients with stage III colorectal and gastric cancer had better survival rates when absolute number of CD3+ lymphocytes, determined before surgery, was greater than 0.8 x 10(9)/L, CD4+--greater than 0.25 x 10(9)/L, CD8+--greater than 0.3 x 10(9)/L. Colorectal cancer patient survived longer when the number of natural killer cells CD16+ was more than 0.25 x 10(9)/L. This study suggests that higher levels of the absolute number of lymphocyte subsets before surgery have a beneficial effect on overall survival of gastric and colorectal cancer patients in stage III.

Treatment of autoimmune diseases in MRL/lpr mice by allogenic bone marrow transplantation plus adult thymus transplantation (102.4)

Abstract MRL/lpr mice (H-2k) with Fas gene mutation develop severe autoimmune diseases, and their hematolymphoid cells such as bone marrow and spleen cells showed a low apoptotic activity by irradiation. Therefore, conventional bone marrow transplantation (BMT) cannot be used to treat autoimmune diseases in these mice (chimeric resistance). In the present study, we examine the effects of additional adult thymus transplantation (TT) from the same donor on successful BMT. When the MRL/lpr mice were lethally irradiated (9.5Gy) and reconstituted with 3 X 107 of C57BL/6 mouse (H-2b) bone marrow cells (BMCs) in conjunction with TT, the mice significantly survived long-term and showed a high donor-derived chimerism in comparison with those treated with BMT alone. Interestingly, the numbers of not only donor-derived T cells but also B cells significantly increased in the mice treated with BMT plus TT even at the early phase of BMT. The number of aberrant CD3+B220+ cells significantly decreased, and the numbers of lymphocyte subsets were also normalized 4 weeks after the treatment. Finally, the autoimmune diseases in MRL/lpr mice could be cured by BMT with TT. These results indicate that the combination of BMT plus TT can overcome the chimeric resistance and treat the autoimmune diseases in MRL/lpr mice.

Lymphocyte–hepatic stellate cell proximity suggests a direct interaction

Recent functional research studies suggest an anti-fibrotic role for natural killer (NK) cells coupled with a profibrotic role for CD8 cells. However, the morphological cellular interplay between the different cell types is less clear. To investigate lymphocyte/hepatic stellate cell (HSC) interactions, hepatic fibrosis was induced by administering carbon tetrachloride (CCl4) intraperitoneally (i.p.) for 4 weeks in C57Bl/6 mice. Animals were killed at 0, 1, 2, 3 and 4 weeks. Liver sections were stained for Sirius red. Confocal microscopy was used to evaluate alpha smooth-muscle actin (alphaSMA) and lymphocyte subsets in liver sections. At weeks 0 and 4, liver protein extracts were assessed for alphaSMA by Western blotting and isolated liver lymphocytes as well as HSC were analysed by fluorescence activated cell sorter (FACS). Similar to the results obtained from classical Sirius red staining and alphaSMA blotting, analysis of liver sections by confocal microscopy revealed a marked and continuous accumulation of alphaSMA staining along sequential experimental check-points after administering CCl4. Although the number of all liver lymphocyte subsets increased following fibrosis induction, FACS analysis revealed an increase in the distribution of liver CD8 subsets and a decrease of CD4 T cells. Confocal microscopy showed a significant early appearance of CD8 and NK cells, and to a lesser extent CD4 T cells, appearing only from week 2. Lymphocytes were seen in proximity only to HSC, mainly in the periportal area and along fibrotic septa, suggesting a direct interaction. Notably, lymphocyte subsets were undetectable in naive liver sections. Freshly isolated HCS show high expression of major histocompatibility complex (MHC) class II and CD11c. In the animal model of hepatic fibrosis, lymphocytes infiltrate into the liver parenchyma and it is thought that they attach directly to activated HSC. Because HSCs express CD11c/class II molecules, interactions involving them might reflect that HSCs have an antigen-presenting capacity.

Treatment of autoimmune diseases in MRL/lpr mice by allogenic bone marrow transplantation plus adult thymus transplantation

MRL/lpr mice (H-2(k)) with Fas gene mutation develop severe autoimmune diseases, and their haematolymphoid cells such as bone marrow and spleen cells showed a low apoptotic activity by irradiation. Therefore, conventional bone marrow transplantation (BMT) cannot be used to treat autoimmune diseases in these mice (chimeric resistance). In the present study, we examine the effects of additional adult thymus transplantation (TT) from the same donor on successful BMT. When the MRL/lpr mice were lethally irradiated (9 x 5Gy) and reconstituted with 3 x 10(7) of C57BL/6 mouse (H-2b) bone marrow cells (BMCs) in conjunction with TT, the mice significantly survived long term and showed a high donor-derived chimerism in comparison with those treated with BMT alone. Interestingly, the numbers of not only donor-derived T cells but also B cells increased significantly in the mice treated with BMT plus TT, even at the early phase of BMT. The number of aberrant CD3+B220+ cells decreased significantly, and the numbers of lymphocyte subsets were also normalized 4 weeks after the treatment. Finally, the autoimmune diseases in MRL/lpr mice could be cured by BMT with TT. These results indicate that the combination of BMT plus TT can overcome the chimeric resistance and treat the autoimmune diseases in MRL/lpr mice.

Immunoglobulin and Lymphocyte Subset Abnormalities in Patients with Fanconi Anemia and Dyskeratosis Congenita.

Fanconi anemia (FA) and dyskeratosis congenita (DC) are genetic disorders characterized by bone marrow failure and an increased risk of acute myeloid leukemia, myelodysplastic syndrome (MDS) and epithelial cancers. While immunological abnormalities have been reported in small numbers of FA and DC patients, their correlation with the evolution of hematologic and neoplastic complications is unclear. To investigate these associations in a prospective cohort we evaluated serum immunoglobulins (IgG, IgA, IgM) and lymphocyte subsets (CD3+, CD4+, CD8+, CD4+/CD8+ ratio, B, and NK cells) in 17 FA and 18 DC patients enrolled in the National Cancer Institute's Inherited Bone Marrow Failure Syndrome (IBMFS) study. All patients were seen at the NIH Clinical Center and had not undergone bone marrow transplantation or received immunosuppressive treatment including corticosteroids in the past 2 years. Their clinical, hematological, immunological and neoplastic features at study entry are summarized in the table. Abnormal values were defined as below the normal range (95% CI).ParameterFA (n=17)DC (n=18)Median age in years (range)18 (5–42)17 (3–47)Any hematological abnormality12 (71%)16 (89%)Any cytopenia9 (53%)16 (89%)MDS3 (18%)0Low absolute lymphocyte count1 (16%)0Low IgG, IgA, or IgM6 (35%)5 (28%)High IgG, IgA, or IgM07 (38%)Low lymphocyte subset4/6 (67%)4/10 (40%)Low immunoglobulins and/or lymphocytes8 (47%)9 (50%)Neoplasm52Fanconi Anemia: 6/17 patients had low immunoglobulin levels. All 5 with normal complete blood counts (CBC) had normal immunoglobulin levels. Among 3 with MDS, 1 had low IgG, IgA and IgM. Among 9 with cytopenias 1 had low IgG, IgA and IgM and 4 had low IgM. Thus 0/5 with normal CBC versus 6/12 with abnormal CBC had at least one low immunoglobulin level (p=0.1). 4/6 patients had abnormal lymphocyte subset numbers; all 4 had decreased CD4+, CD19+ cells and an abnormal CD4+/CD8+ ratio (<1) and 2 had low NK cells. 2/4 with abnormal lymphocyte subset numbers had neoplasms (1 head and neck squamous cell carcinoma [HNSCC], 1 liver adenoma). Taken together, 1/5 with normal CBC (this patient had HNSCC) had abnormal immune parameters (decreased CD4+, CD19+ cells and an abnormal CD4+/CD8+ ratio), compared with 7/12 with abnormal CBC (p=0.15). 2/9 FA patients with normal and 3/8 with abnormal immune parameters had neoplasms (1 lymphoma and vulvar SCC in the former; 1 liver adenoma, 1 HNSCC + MDS, 1 HNSCC in the latter) (p=0.6).Dyskeratosis congenita: 5/18 patients had low immunoglobulin levels (2 IgA, 2 IgG, 1 IgM), and 7 had high levels (2 IgG and IgA, 5 IgA; 1 patient had low IgM and high IgA). 4/10 also had reduced lymphocyte subset numbers (3 low NK cells; 1 low CD19+, CD3+, CD4+ and abnormal CD4+/CD8+ ratio). 9/16 patients with abnormal CBC had abnormal immune studies versus 0/2 with normal CBC (p=1). 1/2 DC patients with SCC had low IgM.Our preliminary screening identified decreased immunoglobulins and/or lymphocytes in ~50% of the FA and DC patients. The decreases were associated with hematological and/or neoplastic complications in all cases. Since CD4+ cells participate in regulation of myeloid hematopoiesis, abnormal numbers of CD4+ cells may contribute to bone marrow failure. Defects in T-helper and NK cell differentiation may increase the risk of neoplasms. Further and larger studies are required to determine the functional importance of these preliminary observations and their correlation with bone marrow failure, MDS, leukemia, or solid tumors.

Pre-Transplant T-Cell Lymphopenia Accelerates Early Donor T-Cell and Myeloid Chimerism but Is Not Required for Full Donor Lymphohematopoietic Engraftment or To Prevent Graft Rejection Following Nonmyeloablative Hematopoietic Cell Transplantation (NST).

To facilitate donor engraftment and prevent graft rejection, some NST regimens incorporate chemotherapy prior to transplant conditioning to induce profound lymphopenia. To characterize the impact of the recipients immune status on donor myeloid and T cell engraftment after NST, we performed a detailed analysis of patient (pt) lymphocyte subsets prior to transplant conditioning. The % and absolute numbers of NK cells, B cells and CD3+/CD4+ or CD3+/CD8+ T-cells expressing HLA-DR, CD25, CD45RO, and CD45RA were quantified by FACS. Factors impacting donor myeloid and T-cell engraftment considered in a multivariate regression analysis included pt age, sex, graft CD34 and CD3 doses, pt pre-transplant lymphocyte subset numbers, absolute lymphocyte counts (ALC), and donor-pt sex mismatch. Forty one pts with a variety of malignancies (n=31) and non malignant hematological disorders (n=10) undergoing a T-cell replete, G-CSF mobilized NST from an HLA-matched donor following cyclophosphamide (Cy )(120mg/kg) and fludarabine (Flu) (125 mg/m2) based NST were analyzed. GVHD prophylaxis consisted of CSA +/− MTX (n=35) or MMF (n=6). Blood was collected on post-transplant days 15,30,45,60 and 100 and sorted into CD14+/CD15+ myeloid and CD3+ T-cell lineages for assessment of chimerism using a short tandem repeat PCR-based chimerism analysis. All pts achieved sustained engraftment of donor myeloid and T-cells with no cases of graft rejection. The median % of donor T-cell chimerism was 94, 100, 100, 98, and 100, at 15, 30, 45, 60 and 100 days post-transplant respectively. In contrast, myeloid engraftment was delayed with the median % of donor myeloid chimerism being 45, 54, 43, 48, and 81 at 15, 30, 45, 60, and 100 days post-transplant respectively. Full donor T-cell chimerism was achieved in all pts at a median 30 (range 15–263) days. Full donor myeloid chimerism was achieved in 33 pts (80%) at a median 100 (range 15–405) days; eight pts died before full donor myeloid chimerism was achieved. Median survival was 499 days (95% C.I. 356–736 days). Univariate analysis showed lower baseline absolute CD3+ cell numbers (p=0.033), older pt age (p=0.046) and lower pt ALC before transplantation (p=0.024) were significantly associated with more rapid donor T-cell engraftment by day 15. Prior chemotherapy exposure (p=0.005), lower baseline numbers of either CD3+cells (p=0.03), CD4+ cells (p=0.03), or CD4+ and CD25+ cells (p=0.01) were all significantly associated with more rapid donor myeloid engraftment by day 15. By multiple regression analysis, lower baseline absolute CD3+ cell numbers (p=0.01) and older pt age (p=0.0002) were significantly associated with more rapid donor T-cell engraftment on day 15 while only prior chemotherapy (p=0.008) exposure facilitated day 15 donor myeloid engraftment. The median time to achieving full donor T-cell chimerism was similar regardless of baseline CD3+ cell numbers.Conclusion: CD3+ lymphopenia facilitates early donor myeloid and T-cell engraftment but does not shorten the time to achieve full donor T-cell chimerism. Induction of CD3+ lymphopenia with chemotherapy before transplant conditioning is not required to achieve full donor chimerism or prevent graft rejection with Cy/Flu-based conditioning used in this regimen.

Modification of lymphocyte subsets in patients with rhinoscleroma

Purpose Rhinoscleroma is a rare, chronic, granulomatous disorder of the upper airways. This disease presents some etiopathogenetic aspects that are not yet clear. Infection by Klebsiella rhinoscleromatis is fundamental for the onset of the disease, but it is impossible to reproduce rhinoscleroma experimentally only via infection with the bacteria both in man and in animals. Furthermore, this disease mainly affects blood-related people and occurs in certain geographic areas. In this context, we present a study that brings to light some of the quantitative abnormalities of the lymphocyte subsets. Materials and methods The study group consisted of 5 patients with rhinoscleroma. The following parameters were studied for each patient: clinical manifestations, histologic examinations, number of leukocytes, lymphocytes, and lymphocyte subsets. Results In all patients, we noted the following: There was a relative reduction of the CD4+ cells, an absolute increase of the CD8+ cells, and an inversion of the CD4+/CD8+ ratio. There was an absolute increase of the CD56+ cells and cytotoxic cells that coexpress CD8+CD56+ antigens. There was a relative reduction of the CD3+ cells, and the CD19+ cells tended to show an ambiguous behavioral pattern. Conclusion We believe that K. rhinoscleromatis does not play a major role in the etiopathogenesis of rhinoscleroma. However, we do believe that the anomalous behavior of the immune system can favor rhinoscleroma.

Augmentation of innate immunity by low-dose irradiation

The effect of low-dose irradiation on the immune system was investigated in mice. When a 0.2 Gy dose of X-ray irradiation was administered every other day for a total of four times, the number of lymphocytes yielded by the liver, spleen and thymus decreased at the initial stage (around day 10). At this stage, NK cells, extrathymic T cells and NKT cells were found to be radioresistant. In other words, conventional lymphocytes were radiosensitive, even in the case of low-dose irradiation. However, the number of lymphocytes in all tested immune organs increased beyond the control level at the recovery stage (around day 28). Enumeration of the absolute number of lymphocyte subsets showed that the most prominently expanding populations were NK cells, extrathymic T cells and NKT cells, especially in the liver where primordial lymphocytes are primarily present. Functional and phenotypic activation of these populations also occurred at the recovery stage. It raised a possibility that an initial activation of macrophages by low-dose irradiation then mediated the present phenomenon. These results suggest that low-dose irradiation eventually has the potential to induce a hormesis effect on the immune system.

The effect of dietary control and carbohydrate supplementation on the immune and hormonal responses to rowing exercise

To determine the effect of carbohydrate supplementation on the immune and stress hormone responses to 1 h of strenuous rowing exercise, 22 male subjects were randomly assigned to a placebo (PLA, n = 11) or carbohydrate (CHO, n = 11) group. Subjects completed 3 d of modified dietary intake, a standardized pre-exercise meal, and consumed either a carbohydrate beverage (1 g.kg body mass(-1)) or a non-caloric placebo drink before, during, and after a 1 h rowing trial. Increases were observed in adrenocorticotrophic hormone, cortisol, blood leukocytes, neutrophils, and natural killer cell concentrations and activity, whereas the ability of peripheral blood monouclear cells (PBMCs) to respond (interleukin-2 (IL-2) production) to stimulation was reduced 5 min after exercise in both groups (p < 0.05). Lymphocytes were also elevated, but in the PLA group only (p < 0.05). One hour after exercise, blood leukocytes remained elevated owing to increased neutrophil concentrations, whereas a number of lymphocyte subsets (CD3+, CD3+/4+, CD3+/8+, CD20+, CD25+, CD4+/25+, CD8+/25+) and the ability of PBMCs to respond to stimulation (IL-2, interferon-gamma (IFN-gamma) production) were lower than resting values in both groups (p < 0.05). Carbohydrate supplementation to athletes in the post-prandial state undergoing a 1 h rowing trial resulted in attenuation of the post-exercise increase in peripheral blood lymphocyte concentration, but had little effect on the ability of PBMCs to produce cytokines following stimulation, natural killer cell activity, stress hormone concentrations, exercise performance, or self-reported incidence of illness during the 14 d period following the experimental trial.

The Influence of an Arduous Military Training Program on Immune Function and Upper Respiratory Tract Infection Incidence

The effects of the first 19 weeks of U.K. Parachute Regiment (PARA) training on upper respiratory tract infection (URTI) incidence and immune function (circulating leukocyte counts, lymphocyte subsets, lipopolysaccharide-stimulated neutrophil degranulation, and salivary immunoglobulin A concentrations) were investigated for 14 PARA recruits and 12 control subjects. No significant differences were reported between groups for the number or duration of URTIs, lymphocyte subsets, or salivary immunoglobulin A concentrations during training. URTI incidence was greater in the PARA group at weeks 2 and 3 (p < 0.05), coinciding with a decrease in circulating leukocyte and lymphocyte counts (p < 0.05). Neutrophil degranulation was similar in the PARA and control groups at weeks 0 and 19. Decreases in saliva flow rate occurred in the PARA group at week 15 and weeks 18 to 20 (p < 0.05). These results show a limited effect of PARA training on URTI incidence and immune function. The progressive decrease in saliva flow rate during PARA training may indicate an ensuing state of hypohydration.

Rapid T-cell Receptor CD4+ Repertoire Reconstitution and Immune Recovery in Unrelated Umbilical Cord Blood Transplanted Pediatric Leukemia Patients

Umbilical cord blood transplantation has been successfully employed for treatment of many immune and hematologic disorders. The aim of this study was to evaluate the quality of immune reconstitution after umbilical cord blood transplantation in 6 leukemia children. T-cell receptor Vbeta third complementary region spectratyping was used for monitoring the contribution of the thymic pathway in patients' immune reconstitution. Absolute numbers of lymphocyte subsets (T, B, and natural killer), and lymphoproliferative in vitro response to mitogens, recovered within 12 months after transplantation. Furthermore, an overall diversification of T-cell receptor complexity in the repopulating T cells, with a polyclonal Gaussian profiles in most (74%) of total families was observed. Noteworthy, we showed a wider and more rapid reconstitution of T-cell receptor CD4+ T cell families compared with T-cell receptor CD8+ T ones still exhibiting some perturbations at 24 months. These data show that umbilical cord blood transplantation allows immune reconstitution already within 12 months with generation of newly diversified CD4+ T lymphocyte subsets.

Tumor Burden Related Immunodeficiency in Lymphoma Patients and Clinical Course.

The association of lymphoma with a plethora of secondary immune defects is well established. However, most investigations were performed many years ago and little is known about disease specific alterations of the immune system. From January 2003 to August 2004 50 patients with newly diagnosed malignant lymphoma were analyzed and compared with 50 healthy volunteers Corresponding in age and gender. Parameters of cellular and humoral immunity, including CBC, FACS analysis of lymphocyte subpopulations, cytokines (sIL2-R, IL-6, IL-10, TNF-a), serum complement components C3c, C4, CH50 and total concentrations of serum immunoglobulin IgG, IgM, IgA were measured. The median number of CD3+ and CD4+ lymphocyte subsets (p≤0.01) were significantly lower in lymphoma patients compared with matched healthy volunteers. The number of CD8+ T-cells was decreased in patients with bulky disease (p≤0.01). High-intermediate/high risk lymphoma (IPI 3-4 or aaIPI 2-3) had significantly higher CH50 (p=0,02), C3c (p≤0,01), sIL2-R (p≤0,01) and TNF-a levels (p=0,05) than patients with low/low-intermediate risk lymphoma. Infectious complications after chemotherapy (n=14) occurred frequently in patients with high initial LDH (p=0,04), low number of CD4+ (p=0,02) or CD8+ T-cells (p=0,04) and high levels of sIL2-R (p=0,02) or TNF-a (p=0,03). Relapse (n=6) was also observed in patients with decreased CD8+ T-cells (p=0,04) and in patients with high C4 levels (p=0,02). These results indicate that tumor burden in lymphoma patients significantly influenced the number of lymphocyte subsets, serum cytokine levels (sIL2R, TNF- a) and complement components (CH50, C3c). IPI-score and clinical course (infections and relapse) were related to the immunodeficiency. We conclude that measurement of peripheral blood lymphocyte subsets, cytokines and complement factors can be expected to improve existing methods of risk assignment in lymphoma.

Low serum transferrin levels in HFE C282Y homozygous subjects are associated with low CD8 + T lymphocyte numbers

Hereditary hemochromatosis (HH) is a genetic iron overload disease, in the majority of cases associated with homozygosity for the C282Y mutation of the HFE gene. In spite of this genetic homogeneity, there is a great clinical heterogeneity among HH patients. Low CD8 + lymphocyte numbers have been associated with a more severe expression of iron overload in HH patients, and in experimental models of iron overload. HH patients present low serum transferrin levels. Transferrin is an indispensable resource for lymphopoiesis. Lymphocyte homeostasis follows general ecology rules of population dynamics that involve competition for limiting resources. In the present study, we questioned whether transferrin levels could be associated with the anomalies seen previously in lymphocyte subset numbers in HH patients. Transferrin levels, total and subset T lymphocyte counts were done in 426 apparently healthy subjects genotyped for HFE. All HFE C282Y carriers presented significantly lower serum transferrin levels than the wild type group, a difference that could not be explained solely by the degree of iron overload. Significant differences were also seen in transferrin levels between males and females, with females presenting higher average serum Transferrin levels. In the population of subjects with Transferrin levels lower than 248 mg/dl, a positive correlation was seen between the peripheral CD8 + lymphocyte numbers and serum transferrin levels ( R 2 = 2.41; r = 0.16; P = 0.018). To test the possible limiting resource effect of transferrin, the correlation between transferrin levels and CD8 + lymphocyte numbers was scrutinized in 34 HH patients, homozygous for the C282Y mutation. In the homozygous males, where the lowest average transferrin levels were seen, another highly significant correlation was observed between Transferrin levels and CD8 + numbers. This correlation points to a possible role of transferrin as a limiting resource for MHC class I dependent lymphocyte proliferation, an effect that was not observed in C282Y homozygous female patients.

Targeting interleukin‐15 in patients with rheumatoid arthritis: A proof‐of‐concept study

Interleukin-15 (IL-15) is a proinflammatory, innate response cytokine that mediates pleiotropic effector function in rheumatoid arthritis (RA) inflammatory synovitis. Our objective was to study the ability of HuMax-IL15, a human IgG1 anti-IL-15 monoclonal antibody, to neutralize exogenous and endogenous IL-15 activity in vitro and to perform a phase I-II dose-escalation trial with HuMax-IL15 in patients with active RA. Mononuclear cells from blood and synovial fluid (SF) of RA patients were isolated and cultured in vitro under experimental conditions involving the addition of HuMax-IL15. HuMax-IL15 was administered to 30 RA patients who received no other disease-modifying antirheumatic drugs in a 12-week, dose-ascending, placebo-controlled, double-blind, phase I-II proof-of-concept study. In vitro studies showed that HuMax-IL15 suppressed proliferation and induced apoptosis in an IL-15-dependent cell line, BDB2, and was capable of suppressing the release of interferon-gamma by synovial fluid mononuclear cell (SFMC) cultures induced by exogenous IL-15. Furthermore, HuMax-IL15 F(ab')2 fragments suppressed exogenous IL-15-induced CD69 expression in RA peripheral blood mononuclear cells and SFMCs, which indicates that HuMax-IL15 can specifically neutralize several biologic effects of IL-15 in synovial tissue in vitro. In a phase I-II clinical trial, HuMax-IL15 was well tolerated clinically, with no significant effects on T lymphocyte subset and natural killer cell numbers. Substantial improvements in disease activity were observed according to the American College of Rheumatology criteria for 20% improvement (63% of patients), 50% improvement (38%), and 70% improvement (25%). These clinical data suggest for the first time that IL-15 could represent a novel therapeutic target in RA.

Polyethylene Glycol-Conjugated Adenosine Deaminase (ADA) Therapy Provides Temporary Immune Reconstitution to a Child with Delayed-Onset ADA Deficiency

We describe the effects of polyethylene glycol-conjugated adenosine deaminase (ADA) replacement therapy on lymphocyte counts, activation, apoptosis, proliferation, and cytokine secretion in a 14-month-old girl with "delayed-onset" ADA deficiency and marked immunodysregulation. Pretreatment lymphopenia affected T cells (CD4, 150/microl; CD8, 459/microl), B cells (16/microl), and NK cells (55/microl). T cells were uniformly activated and largely apoptotic (CD4, 59%; CD8, 82%); and T-cell-dependent cytokine levels in plasma were elevated, including the levels of interleukin 2 (IL-2; 26 pg/ml), IL-4 (81 pg/ml), IL-5 (46 pg/ml), gamma interferon (1,430 pg/ml), tumor necrosis factor alpha (210 pg/ml), and IL-10 (168 pg/ml). Mitogen-stimulated peripheral blood mononuclear cells show reduced IL-2 secretion and proliferation. During the first 5 months of therapy there was clinical improvement and partial immune reconstitution, with nearly normal lymphocyte subset numbers, reduced T-cell activation and CD4-cell apoptosis, and decreased plasma cytokine levels. In parallel, IL-2 secretion and the lymphocyte mitogenic response improved. Between 4 and 7 months, immunoglobulin G antibodies to bovine ADA developed and resulted in the complete reversal of immune recovery.

Assessing donor chimerism level among CD3 T, CD4 T, CD8 T, and NK cells predicts subsequent graft rejection, GVHD, and relapse after allogeneic HCT with nonmyeloablative conditioning

We previously showed that low levels of day-14 CD3 T and NK (CD56) cells donor chimerism predicted graft rejection, whereas high levels of day-28 CD3 T-cell donor chimerism predicted acute graft-versus-host disease (GVHD) after HCT with nonmyeloablative conditioning. Here we investigate whether assessing chimerism levels among CD4 T cells and CD8 T cells, and also the absolute number of lymphocyte subsets of donor and host origins, would lend greater precision to our initial observations. We analyzed data from 157 patients receiving HCT after conditioning with 2 Gy TBI +/− fludarabine as treatment for AML (n= 22), ALL (n= 4), CML (n= 13), CLL (n= 19), MDS (n= 26), MM (n= 24), NHL (n= 30), HD (n= 14), RCC (n= 4), and WASP deficiency (n= 1).

Lateralized neocortical control of T export from rat thymus: Increased export after left Temporo-Parieto-Occipito (TPO) cortical stimulation medicated by sympathetic pathways in upper spinal cord

RATIONALE: Lateralization of cerebral cortical function for language, spatial problem solving and affect is well established. A similar relationship to immune function has been suggested, but remains controversial. In a new rat model, we determined if TPO stimulation modulates blood lymphocyte subset numbers.

Acute stress reduces intraparenchymal lung natural killer cells via beta-adrenergic stimulation

There are lines of evidence that natural killer (NK) cells are sensitive to physical and psychological stress. Alterations in the immune system including NK cells are known to differ among tissues and organs. The effect of stress on the lung immune system, however, has not been well documented in spite of the fact that the lungs always confront viral or bacterial attacks as well as tumour cell metastasis. In this study, we intended to investigate the effect of restraint stress on lung lymphocytes including NK cells. C57BL/6 mice were exposed to 2 h restraint stress. The concentration of plasma epinephrine significantly rose immediately after the release from restraint as compared to home-cage control mice. Flow cytometric analysis revealed that the numbers of most lymphocyte subsets including NK cells were decreased in the lungs and blood but not in the spleen, immediately after restraint stress. Immunohistochemical examination revealed that the number of NK cells was decreased in the intraparenchymal region of the lungs, while the number of alveolar macrophages did not change. The decrease in the number of NK cells in the lungs and blood was reversed by the administration of propranolol, a nonselective beta adrenergic antagonist. Taken together, our findings suggest that acute stress reduces the number of intraparenchymal lung NK cells via activation of beta adrenergic receptors.