PubMed Health⌕ Search

SEARCH · PubMed Health

Results for “Lymphocyte Count”

Explore indexed PubMed citations for clinical trials, systematic reviews and public health research. Read source abstracts and follow each citation to its original PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 667 records · Page 37Linked to original sources

Immunomodulating effects of surgical intervention in tumors of the head and neck.

The immunomodulating effect of primary surgical intervention in 33 patients with squamous cell carcinoma of the oral cavity, pharynx, and larynx was analyzed prospectively. An operation time of longer than 7 hours was significantly associated with a decrease of total lymphocyte counts, CD4(+) T lymphocytes, and CD8(+) T lymphocytes. The CD4/CD8 ratio as a marker for the downregulation of the cellular immune response was slightly decreased but still in the normal range. CD4(+) lymphocyte counts increased within 7 days, and CD8(+) lymphocytes increased 4 weeks after the operation. The in vitro stimulation of the lymphocytes was impaired for 1 to 4 weeks. Release of interleukins, interferon-gamma, and tumor necrosis factor-alpha remained low despite the surgical trauma. The decreased lymphocyte counts, especially CD4(+) and CD8(+) lymphocytes, were significantly associated with duration of operation and volume of blood loss. Extension of trauma, age, type of anesthesia, and type of intensive care intervention were not associated with specific immunomodulating effects. However, these factors might be responsible for suppression of the immune system, which is expressed by lymphocyte depletion, lymphocyte dysfunction, and impaired upregulation of cytokine secretion.

Adult↗

Brief report: effect of antiretroviral agents on T-lymphocyte subset counts in healthy HIV-negative individuals. The Italian Registry on Antiretroviral Postexposure Prophylaxis.

To study the effect of antiretroviral agents on T-lymphocyte counts in HIV-negative individuals, total counts and CD4+ and CD8+ lymphocyte counts were measured in health care workers (HCW) who had been occupationally exposed to HIV who were untreated (164 HCW, group A), or had received antiretroviral postexposure prophylaxis (PEP). PEP included zidovudine (150 HCW, group B), zidovudine plus lamivudine (48 HCW, group C), or zidovudine, lamivudine, and indinavir (85 HCW, group D), at standard dosage for a mean of 30, 27, and 27 days of treatment, respectively. Lymphocyte values were collected after a mean of 44 days following exposure in group A, 48 days in group B, and 30 days both in groups C and D. Student's t-, nonparametric Mann-Whitney, and Kruskal-Wallis tests were used for statistical analysis. A slight increase in mean CD4 (range, 4.8%-6. 7%) and CD8 (range, 1.4%-9.3%) cells/mm3 was observed in each group. Gender, PEP duration, side effects, and follow-up time did not correlate with responses. Data did not vary using CD4 and CD8 percentages. These findings seem to reject any direct effects of antiretroviral agents, independent of retroviral inhibition, on proliferation and redistribution of T lymphocytes, as well as the hypothesized braking of lymphocyte apoptosis. The observed variations could reflect biologic variability.

Anti-HIV Agents↗

Difference in effect of single immunosuppressive agents (cyclophosphamide, CCNU, 5-FU) on peripheral blood immune cell parameters and central nervous system immunoglobulin synthesis rate in patients with multiple sclerosis.

Cyclophosphamide (CY), 1-(2-chloroethyl)-3-cyclohexyl-1-nitrosourea (CCNU) and 5-fluorouracil (5-FU) were given in single course schedules to chronic progressive multiple sclerosis (MS) patients clinically stable for 6 months. The following peripheral immune cellular parameters were measured before, during and after each drug administration: white blood count (WBC), polymorphonuclear count (PMN), lymphocyte count, percentage of T cells, T cell response to phytohaemagglutinin (PHA), percentage of B cells, percentage of cells bearing receptors for the Fc portion of immunoglobulin (% FcR cells), killer (K) cell activity defined by antibody-dependent cellular cytotoxicity (ADCC), and natural killer (NK) cell activity. Central nervous system (CNS) immunoglobulin G (IgG) synthesis was also measured. The patients were followed carefully by both quantitative and qualitative methods for any change in their neurologic condition. Selective reduction in NK activity was observed with CY and 5-FU while no significant alteration was seen in %FcR cells and K activity. CY differed from 5-FU in reducing lymphocyte count and B cell percentage while 5-FU decreased the percentage of T cells. CCNU, but not the other drugs, reduced T cell proliferative response to PHA. In addition, CCNU, which is known to penetrate well into the nervous system, caused a modest reduction in CNS IgG synthesis, while 5-FU had an uncertain effect. Clinically the patients were unchanged or continued to progress in their disability. The results suggest an independence of the CNS immune from the systemic immune system in MS in response to many immunosuppressive drugs.

Adult↗

Immunological manifestations of HIV-infected children.

This cross-sectional study of stable HIV-infected children was designed to document the immunological manifestations of paediatric HIV infection and to determine whether inexpensive markers of immunosuppression could be identified. Investigations included lymphocyte count and subset analysis, levels of total protein, albumin, immunoglobulins, beta-2 microglobulin and neopterin. The median age of the 74 children studied was 16.5 months and 76% and 39% had subnormal percentage CD4+ counts and absolute CD4+ counts, respectively. According to the Centers for Disease Control (CDC) guidelines, 85% were moderately or severely immunosuppressed. The majority had elevated neopterin, beta-2 microglobulin, IgG, IgM and IgA concentrations. The IgG concentration correlated positively with total globulin, IgG1 and IgG3 concentrations. On bivariate analysis, the absolute CD4+ count correlated positively with total lymphocyte count (r = 0.28 < 0.48 < 0.64) and negatively with total IgG concentration (r = -0.47 < -0.27 < -0.04), IgG1 concentration (r = -0.51 < -0.31 < -0.08), and neopterin concentration (r = -0.49 < -0.28 < -0.04). There was no correlation between CD4+ count, total globulin or beta-2 microglobulin concentration. On multiple linear regression analysis only the total lymphocyte count correlated with CD4+ count. Furthermore, on bivariate analysis total lymphocyte count correlated positively with absolute CD8+ count (r = 0.82 < 0.88 < 0.92). In conclusion, although there was a positive correlation between absolute CD4+ count and total lymphocyte count, the clinical significance is questionable as the total lymphocyte count correlated more strongly with the absolute CD8+ count.

Analysis of Variance↗

CD4 lymphocyte enumeration in patients with human immunodeficiency virus infection using three-colour and four-colour dual-platform flow cytometry: an inter-laboratory comparative evaluation.

INTRODUCTION: This study aims to evaluate the correlation and agreement between 2 methodologies of CD4 lymphocyte enumeration. MATERIALS AND METHODS: Fifty-two blood samples from patients with human immunodeficiency virus (HIV) infection were sent for CD4 lymphocyte enumeration at 2 major hospitals using dual-platform flow cytometry where the absolute lymphocyte counts were determined on separate haematology analyzers. CD4 cell enumeration was accomplished using 3-colour flow cytometry on the FACSCalibur cytometer (Becton Dickinson) in Hospital A and 4-colour flow cytometry on the Coulter Epic XL cytometer (Beckman Coulter) in Hospital B. The percentages and absolute counts of CD4 lymphocytes obtained were analysed using both linear regression and Bland-Altman plots. RESULTS: On linear regression plots, the total white cell counts, absolute lymphocyte counts, CD4 lymphocyte percentages and absolute CD4 counts from the 2 hospitals correlated well with correlation coefficients, r > 0.95. On the Bland-Altman plots, there was a mean difference of 0.13 x 10(9)/L and 0.06 x 10(9)/L in the total white cell and absolute lymphocyte counts from the 2 hospitals respectively. The CD4 lymphocyte percentages revealed a mean difference of only 0.05% (95% limits of agreement, -3.6 to 3.7%) but there was a mean difference of 14/uL in the absolute CD4 lymphocyte counts (95% limits of agreement, -113 to 142/uL). CONCLUSIONS: The CD4 lymphocyte percentages obtained using the 3-colour and 4-colour flow cytometry correlated and agreed well. However, the absolute CD4 lymphocyte counts obtained using the dual-platform technique in both the hospitals did not agree well. Hence, absolute CD4 lymphocyte counts from the 2 hospitals cannot be used interchangeably in clinical practice due to poor inter-laboratory comparability.

CD4 Lymphocyte Count↗

Lymphocyte subsets in patients with oestrogen deficiency.

We have previously shown that in patients with idiopathic premature ovarian failure there were significant changes in lymphocyte subsets. To test our hypothesis that these changes were due to oestrogen deficiency we studied lymphocyte subsets in patients with oestrogen deficiency due to other causes. Blood was taken for serum oestradiol, lymphocyte counts and lymphocyte subset counts (CD2+, CD4+, CD8+ and B cells) before oestrogen replacement in 19 patients with gonadal dysgenesis, 22 patients with hypothalamic-pituitary failure and 24 healthy female control subjects. The CD4:CD8 ratio in both groups of patients was significantly lower than that in the normal control subjects while the percentages and counts of lymphocytes and CD8+ cells were significantly higher. There was a significant positive correlation between the serum oestradiol level and the CD4:CD8 ratio. These findings support the hypothesis that the changes in lymphocyte subsets are due to oestrogen deficiency.

Antigens, CD↗

Association between CCR5 genotype and the clinical course of HIV-1 infection.

BACKGROUND: Heterozygosity for a 32-nucleotide deletion in the C-C chemokine receptor 5 gene (CCR5 delta 32) is associated with delayed disease progression in persons infected with HIV-1. OBJECTIVE: To compare the predictive value of CCR5 genotype with that of established markers in the clinical course of HIV-1 infection. DESIGN: Retrospective longitudinal study and nested case-control study. The latter included only long-term survivors, who were individually matched with progressors. SETTING: Amsterdam, the Netherlands. PARTICIPANTS: 364 homosexual men with HIV-1 infection. MEASUREMENTS: Polymerase chain reaction was used for CCR5 genotyping. Univariate and multivariate Cox proportional hazard analyses were done for disease progression with CCR5 genotype, CD4+ T-lymphocyte counts, T-lymphocyte function, HIV-1 biological phenotype (syncytium-inducing or non-syncytium-inducing HIV-1), and viral RNA load in serum as covariates. RESULTS: In the case-control study, 48% of long-term survivors were heterozygous for CCR5 delta 32 compared with 9% of progressors (odds ratio, 6.9 [95% CI, 1.9 to 24.8]). In the total study sample, CCR5 delta 32 heterozygotes had significantly delayed disease progression (P < 0.001; relative hazard, 0.4 [CI, 0.3 to 0.6]), a 1.5-fold slower decrease in CD4+ T-lymphocyte count (P = 0.01), and a 2.6-fold lower viral RNA load (P = 0.01) at approximately 2.3 years after seroconversion compared with CCR5 wild-type homozygotes. At the end of the study, both groups showed the same prevalence of syncytium-inducing HIV-1, but CCR5 delta 32 heterozygotes had a delayed conversion rate. The protective effect of CCR5 delta 32 heterozygosity was stronger in the presence of only non-syncytium-inducing HIV-1. The CCR5 genotype predicted disease progression independent of viral RNA load, CD4+ T-lymphocyte counts, T-lymphocyte function, and HIV-1 biological phenotype. CONCLUSIONS: The addition of CCR5 genotype to currently available laboratory markers may allow better estimation of the clinical course of HIV-1 infection.

Acquired Immunodeficiency Syndrome↗

Long-term follow-up of general immune competence in breast cancer. II. Sequential pre- and post-treatment levels: a 10 year study.

Pre-treatment and sequential post-treatment (at 3 months, 6 months, 1, 2, 3, 4 and 5 years) examination of general immune competence was performed in 185 consecutive breast cancer patients. The patients were followed for 5 to 11 years to monitor the dynamic relationship between host immunity and cancer and to examine the effect of the treatment method. The tests of immune competence used were immunoglobulins IgG, IgA, IgM, leucocyte counts, percentage and total lymphocyte counts and Mantoux and DNCB skin hypersensitivity tests. Serum IgG and IgA showed no change relating to treatment method in recurrence-free patients; but IgG levels were higher when recurrent disease was imminent or established; IgM diminished (P less than 0.001) after treatment and this continued at 5 years in all patient groups. Simple lymphocyte counts showed the most interesting changes. They remained depressed for as long as 60 months following radiotherapy (P less than 0.01). After treatment by surgery, lymphocyte counts rose in patients without recurrence, but fell when systemic recurrence was imminent or established. This effect was not seen in patients with local recurrence only. There was no change in immune competence immediately before recurrence sufficient to be of clinical usefulness, but a low pre-treatment lymphocyte count with a steady rise after surgery carried a good prognosis. Similarly a high initial lymphocyte count with a fall after surgery was indicative of recurrence. Universal and prolonged depression of lymphocyte counts following radiotherapy was confirmed, and the effect was additive to that of tumour load in recurrent disease. Because of the large number of statistical calculations carried out, some of the apparently significant findings may be due to chance. However, the general trends emerging suggest that similar long-term studies, using the more sophisticated measures of lymphocyte function now available, might be rewarding.

Breast Neoplasms↗

Phase-II randomized study of pre-operative IL-2 administration in operable NSCLC.

Lymphocytopenia is a prognostic factor for shorter survival in advanced lung cancer and it is likely related to an interleukin-2 (IL-2) deficiency occurring during cancer progression. Major surgery itself for cancer is known to induce lymphocytopenia in the postoperative period. Postoperative lymphocyte decrease in colorectal cancer can be prevented by preoperative administration of recombinant human (rhIL-2), indicating that it is possible to drive appropriately important host defence agents during critical events, such as major surgery. The aim of this study is to verify if recombinant human interleukin-2 (rhIL-2) administered preoperatively is able to prevent the lymphocyte decrease occurring after radical surgery in operable lung cancer. This phase II study included 40 patients with operable NSCLC screened as stage II or IIIA, randomized to receive rhIL-2, 9000000 IU subcutaneously twice daily for 3 days before surgery (treated group, 20 patients) or not (control group, 20 patients). At baseline, there were no significant differences in total lymphocyte number and lymphocyte subsets (T-cell, T-helper, CD8+, natural killer, CD4/CD8 ratio) between groups. Postoperatively the control group showed a decrease in total lymphocyte count, T-lymphocyte count, T-helper cell number and CD4/CD8 ratio, significant at the 14th postoperative day relative to baseline values. In contrast, in the rhIL-2 treated group, at the 3rd and at the 14th postoperative days, a significant increase was observed over both baseline and control group values of total lymphocyte count, T-cells and T-helper cells. NK cell number increased significantly only over the control group. CD4/CD8 ratio was increased at the 14th postoperative day significantly over both baseline and control values. At pathological staging after surgery, four patients in the rhIL-2 group and four in the control group resulted in stage pIIIB; one patient in the rhIL-2 group resulted in stage IV (contralateral metastasis). Indeed, 15/20 rhIL-2 treated patients and 16/20 control patients were radically operated. After a 24-month follow-up, 12/20 rhIL-2 treated patients were alive and 8/15 radically operated were disease-free; 8/20 control patients were alive and 4/16 radically operated were disease-free. Toxicity was mild to moderate and easy manageable; treatment was suspended in one patient due to skin rash with hypotension grade II. The preoperative administration of rhIL-2 is feasible and prevents lymphocyte decrease occurring postoperatively after surgery for lung cancer. Further studies are required to assess the impact on survival.

Adult↗

Hematologic differences in heterophile-positive and heterophile-negative infectious mononucleosis.

Infectious mononucleosis (IM) due to all causes is characterized by atypical lymphocytosis. We sought to compare hematologic parameters of infectious mononucleosis due to Epstein-Barr virus (EBV) infection (heterophile antibody (HA) positive) with mononucleosis due to other causes. Mono-Latex Slide Agglutination Test results and complete blood counts (CBC) of 147 patients with mononucleosis were retrospectively analyzed. Leukocyte count, absolute lymphocyte count, and presence of atypical lymphocytes in EBV-positive and EBV-negative groups were statistically compared. We analyzed 68 EBV-positive and 79 EBV-negative cases. EBV-positive patients were significantly younger than EBV-negative patients were. Mean total WBC count and mean absolute lymphocyte count were significantly higher in EBV-positive patients. Absolute lymphocytosis, absolute leukocytosis, and atypical lymphocytosis were also significantly more frequent in EBV-positive patients. Leukopenia was more frequently seen in EBV-negative patients.

Adolescent↗

Lymphocyte homeostasis in HIV-infected northern Thais.

Cross-sectional laboratory data were used to model the patterns of total lymphocyte count and lymphocyte subpopulation counts among persons with chronic HIV-1 subtype E (CRF01_AE) infection during the 6.5 years preceding death. The data cover 331 HIV-infected decedents from a heterosexual HIV transmission study of 590 northern Thai couples enrolled in 1992-1998. From blood collected at enrollment, the lymphocyte phenotypes (CD3, CD8, CD4, natural killer, and B cells) were stained using two-color monoclonal antibody combinations and quantified by flow cytometry. Piecewise linear splines modeled the associations between lymphocyte levels and time before death. Mean CD3, CD8, and B cell levels showed no temporal associations from 6.5 to 2 years before death, but each declined significantly during the 2 years before death. CD3 levels declined 31.0% [95% confidence interval (-40.3%, -19.8%)] and CD8 levels declined 24.6% (-35.4%, -13.5%) annually in the 2 years prior to death. In contrast, CD4 and NK cell levels declined little from 6.5 to 4.5 years before death but declined significantly over the 4.5 years prior to death. CD4 levels declined 22.1% (-29.2%, -12.0%) annually from 4.5 to 2 years prior to death and 63.7% (-72.3%, -53.6%) annually over the remaining 2 years. Similar lymphocyte patterns have been reported in U. S. and European populations with HIV-1 subtype B infection.

Adolescent↗

Lymphocyte subsets in cord blood of preterm infants: effect of antenatal steroids.

The objective of this study was to evaluate prospectively the influence of gestational age (GA) and short-term antenatal steroids on total lymphocyte count and lymphocyte subsets in cord blood from preterm infants. Two-color flow cytometric analyses of lymphocyte subsets were performed on cord blood collected from 67 infants. These infants were grouped according to GA: group I (term, n = 19); group II (GA 33-37 weeks, n = 25); group III (GA <33 weeks, n = 23). The mean absolute lymphocyte counts (ALC) in groups I, II and III were 5.6 +/- 2.5 x 10(3)/ microl, 4.3 +/- 1.5 x 10(3)/ microl and 3. 5 +/- 1.8 x 10(3)/ microl respectively. The mean values for CD4+ lymphocytes in groups I, II and III were 2.7 +/- 0.8 x 10(3)/ microl, 2.0 +/- 0.8 x 10(3)/ microl and 1.6 +/- 0.9 x 10(3)/ microl respectively. Mean values for CD8+ lymphocytes were 0.9 +/- 0.3 x 10(3)/ microl, 0.6 +/- 0.3 x 10(3)/ microl and 0.5 +/- 0.3 x 10(3)/ microl respectively. With decreasing GA, there was a statistically significant decrease in ALC (p = 0.0035), CD4+ lymphocytes (p = 0. 0013) and CD8+ lymphocytes (p = 0.0064). We then evaluated the effect of antenatal steroids, now routinely administered to women with preterm onset of labor to facilitate fetal lung maturation, and found that after adjusting for GA, infants of women on antenatal steroids had significantly fewer ALC (p = 0.0001), CD4+ lymphocytes (p = 0.02) and CD25+ lymphocytes (p = 0.03). In this population of infants, the decreased number of lymphocytes seen at younger GAs is associated with antenatal steroid use.

Betamethasone↗

Hematological recovery in male ultramarathon runners: the effect of variations in training load and running time.

AIM: Haematological response to the 2001 downhill Comrades Marathon was compared in high (>120 km/w in training; 3 weeks of pre-race taper) and low (<80 km/w in training; 2 weeks of pre-race taper) training status groups. METHODS: Full blood counts, differential lymphocyte counts (CD3, CD4, CD8, CD19, CD56), serum cortisol, C-reactive protein (CRP) and creatine kinase (CK) were measured in blood samples donated 21 hours before and 16 hours after a 90 km ultramarathon. RESULTS: Despite significantly faster mean race finishing time (8.03 h vs 10.53 h; p<0.001) and greater percentage incidence (55.6% vs 40%) of post-race upper respiratory tract infection (URTI) in the highly trained group, these faster runners did not show evidence of a slower post-race recovery in terms of total leukocyte, neutrophil, total or differential lymphocyte counts (p>0.05). CRP concentrations were, however, markedly higher in the slower, less trained group (65.3+/-10.7 vs 38.3+/-5.9; p<0.01). CONCLUSIONS: Despite greater systemic evidence of post-race muscle inflammation and an acute phase response in the slower runners in a downhill ultramarathon race, the haematological recovery of well trained runners who undergo a 3-week taper period prior to the ultramarathon is not different to that in less trained runners who spend almost 3 hours longer on the road. The higher prevalence of post-race URTI symptoms in the fast, well trained group does not appear to be related to lymphocyte recovery in peripheral blood.

Adult↗

Immunological profile of endemic and epidemic Kaposi's sarcoma patients in Dar-es-Salaam, Tanzania.

Kaposi's sarcoma (KS) presents in four clinicopathological types namely classical/sporadic (CKS), endemic African (EKS), iatrogenic (IKS) and that associated with AIDS (AKS). Recently a putative herpes virus (HHV-8) was described and shown to be present in all four types of KS. The immunological status of patients with EKS has been conflicting. In this study total leucocyte counts, total lymphocyte counts and lymphocyte subsets of patients with EKS and AKS were determined by flow cytometry and compared to those of healthy HIV-1 seronegative controls. Results show that 50% of EKS lesions were of nodular type. Patients with EKS had significantly lower levels of CD4+ T- lymphocytes and CD4:CD8 ratio but significantly higher CD8+ T-lymphocytes compared to controls. Patients with AKS had significantly lower levels of CD4+ T-lymphocytes and also CD4:CD8 ratios but significantly higher percentage of CD8+ T-lymphocytes when compared with EKS patients. These findings indicate that in both forms of KS there is a certain degree of immunological disturbance which is more conspicuous in AKS because of HIV infection and suggests that HIV-1 acts synergistically with the aetiological agent (HHV-8) to cause a more aggressive type of KS.

AIDS-Related Opportunistic Infections↗

An in vitro and in vivo study of cytokines in the acute-phase response associated with bisphosphonates.

We studied the acute phase response, including specific cytokine production, [interleukin-1 (IL-1), interleukin-6 (IL-6), tumor necrosis factor alpha(TNF alpha)] following a single dose of Aredia (disodium pamidronate) in patients with increased bone turnover and, in vitro, the role played by specific cytokines in the acute-phase reaction which may follow the administration of aminobisphosphonates. An in vivo exploratory study was done on 24 in- and outpatients with increased bone turnover given a single intravenous dose of pamidronate 60 mg. Measurements were taken at baseline and at 24, 48, and 72 hours. The main outcome measures were changes from baseline in serum IL-1, IL-6, and TNF alpha. In addition, C-reactive protein (CRP), white blood cell count (WCC), lymphocyte count, and elastase concentration were measured. Symptomatic evaluation was made of fever, bone pain, and rigors. In vitro, whole blood from eight healthy volunteers was exposed to various concentrations of the three bisphosphonates--pamidronate, clodronate, and zoledronate. Measurements were taken immediately before and at 3, 6, and 10 hours after exposure to drugs. The main outcome measures were changes in serum IL-1, IL-6, and TNF alpha. In vivo, there was a statistically significant (P < 0.001) increase in median values of TNF alpha in all post-baseline measurements. Median values for IL-6 also showed a significant (P < 0.001) increase at 24 hours after dosing. There were no statistically significant changes in median IL-1 values. Few patients showed any change from baseline in total WCC or in lymphocyte count, but 62.5% of patients with normal range baseline values for CRP increased to above normal levels after treatment. Fourteen patients experienced fever; 2 reported rigors. There was no correlation between fever and changes in cytokines. There were no serious adverse experiences or premature discontinuations due to poor tolerability, and 91% of the patients expressed willingness to receive pamidronate again. In vitro, an increase in TNF alpha and a mild increase in IL-6 was seen with all bisphosphonates, with the greatest effects seen with the highest concentration of both pamidronate and zoledronate. No changes were observed in IL-1 with any agent. Significant changes in both TNF alpha and IL-6 were observed within 3 days of a single dose of pamidronate in patients treated for the first time confirming previous findings. However, the lack of change in IL-1 in vivo and in vitro does not support the hypothesis that this cytokine plays a major role in the acute phase reaction. The cellular mechanism of the interaction among aminobisphosphonates, IL-6, and TNF alpha requires further investigations. The results of the in vitro study are consistent with the in vivo findings.

Acute-Phase Reaction↗

Defining the optimal spacing between repeat radioantibody doses in experimental models: is there an accurate measurement for hematopoietic recovery?

BACKGROUND: Single doses of radioantibody are effective at treating single cells or small clusters of cancer cells. However, large tumor masses require either multiple doses of radioantibody or a multimodal approach to therapy using two or more therapeutic agents. Timing of the second dose in a multiple cycle scheme or the second treatment in a multimodal protocol will depend on recovery from toxicity associated with the first treatment. METHODS: BALB/c mice were dosed with a maximal tolerated dose (MTD) of I-131-MN-14 anti-carcinoembryonic antigen immunoglobulin G (IgG) (250 microCi) or F(ab')2 (1.2 mCi). Mice were redosed with the MTD at one of four time points, either Day 28, 35, 42, or 49 after IgG or Day 14, 21, 28, or 35 after F(ab')2. Survival was monitored to determine the earliest time to redose without lethality. Several studies were then performed to identify an accurate measure of true myelorecovery. Mice were bled retroorbitally on the day of the first dose and at weekly intervals thereafter. Total peripheral white blood cell counts, granulocyte counts, and lymphocyte counts were determined for each animal. GR-1hi expression (percentage of positive cells) and mean channel florescence were determined by FACScan analysis of a blood sample incubated with fluorescein isothiocyanate-anti-mouse Ly-6G (GR-1). In other studies, two mice were killed weekly from a group treated with a single MTD of radioantibody. The weights of their spleens and thymus glands were determined. At that time, femoral marrow was collected from these animals and plated in Methocult M3430 methylcellulose medium (Stemcell Technologies, Vancouver, Canada), and total colony-forming cells in culture were determined. Another population of mice was used to assess normal tissue metabolic activity following radioantibody therapy by quantitating the 4-hour utilization of I-125-dUrd. RESULTS: The ability to redose mice with a second MTD of 1-131-IgG or F(ab')2 required 49 days and 35 days, respectively. Granulocyte and lymphocyte counts did not accurately predict myelorecovery from the first dose. Hematopoietic tissue weight, tissue metabolic activity, and marrow colony forming cells all suggested that redosing was possible 1-2 weeks before it could actually be done without lethality. Percent of cells expressing GR-1hi (>60%) and absolute numbers of GR-1hi cells (>1400 cells/mm3) suggested myelorecovery in most animals. A greater degree of accuracy was achieved when trends in GR-1hi expression were noted over 2 or more weeks (i.e., the absolute amount of GR-1hi had to exceed levels in untreated mice, as evidence that the hyperproliferative phase of recovery was complete). CONCLUSIONS: The only approach that accurately predicted the ability to retreat with myelosuppressive therapy without risk of lethality was an increase in GR-1hi-positive cells above untreated levels. Other approaches are currently being investigated, including the expression of proliferation antigens (e.g., proliferating cell nuclear antigen and Ki-67) in both murine and human samples and differentiation antigens (CD33 and CD34) in humans.

Animals↗

Long-term follow-up of 120 patients with AIDS-related Kaposi's sarcoma treated with interferon alpha-2a.

One hundred and twenty patients suffering from an AIDS-related Kaposi's sarcoma treated by 18 million units of recombinant alpha-2A-interferon daily were followed prospectively for a period of between one and six years. An overall complete response was observed in 35% of these patients; the figure was significantly higher in those who did not have a visceral localization or opportunistic infections. Total lymphocyte count, CD4 lymphocyte count, and CD4/CD8 ratio were significantly higher, and beta-2-microglobuline significantly lower, in the responders than in the non-responders. A multivariate analysis showed that localization of KS and CD4 count had independent predictive value, with an odds ratio of 35 for patients who had more than 300 CD4 cells at the onset of treatment versus those with less than 150. Patients whose initially negative p24 antigenemia remained negative during treatment had the highest frequency of complete response. Among patients with initially positive p24 antigenemia, those whose percentage decrease in antigenemia levels was greatest had a higher frequency of complete response. The cumulative probability of survival in responders was 62% at four years. These results demonstrate an anti-tumoral and anti-viral effect and prolonged survival in a group of patients whose initial immune parameters were relatively well preserved. However, these results do not permit us to conclude whether these well-responding patients were treated at the onset of illness, or whether their illness was naturally less evolutive.

Acquired Immunodeficiency Syndrome↗

Orthopaedic procedures and prognosis in hemophilic patients who are seropositive for human immunodeficiency virus.

Thirty patients who had hemophilia and were seropositive for the human immunodeficiency virus were evaluated. The preoperative CD4 lymphocyte count was decreased to an average of 336 x 10(9) per liter (range, 27 to 708 x 10(9) per liter). After twenty-six orthopaedic operations in patients who had no previous bacterial infection, a nosocomial infection (cellulitis in the forearm, at the site of an intravenous catheter) developed in only one patient, but five patients had an abnormal postoperative fever that was not accompanied by the expected increase in the white blood-cell count. The preoperative CD4 lymphocyte count was significantly reduced in the patients who had an abnormal elevation in body temperature (p less than 0.004). The functional result or outcome after operation was similar to that in hemophilic patients treated before 1982. Subsequent progression of infection with the human immunodeficiency virus, as determined by the CD4 lymphocyte count and the Walter Reed classification system, occurred in most patients. Acquired immunodeficiency syndrome was diagnosed in six patients. A more rapid progression to acquired immunodeficiency syndrome was seen in the patients who had a lower CD4 lymphocyte count preoperatively. Preoperative evaluation of the CD4 lymphocyte count and the response to intradermal skin-test antigens in patients who are at risk for infection postoperatively provides additional information concerning immunological competence. With these data, the possible risk of infection in patients who are seropositive for the human immunodeficiency virus can be estimated more accurately.

Acquired Immunodeficiency Syndrome↗