We use cookies to distinguish you from other users and to provide you with a better experience on our websites. Close this message to accept cookies or find out how to manage your cookie settings.
Online ordering will be unavailable from 17:00 GMT on Friday, April 25 until 17:00 GMT on Sunday, April 27 due to maintenance. We apologise for the inconvenience.
To save content items to your account,
please confirm that you agree to abide by our usage policies.
If this is the first time you use this feature, you will be asked to authorise Cambridge Core to connect with your account.
Find out more about saving content to .
To save content items to your Kindle, first ensure [email protected]
is added to your Approved Personal Document E-mail List under your Personal Document Settings
on the Manage Your Content and Devices page of your Amazon account. Then enter the ‘name’ part
of your Kindle email address below.
Find out more about saving to your Kindle.
Note you can select to save to either the @free.kindle.com or @kindle.com variations.
‘@free.kindle.com’ emails are free but can only be saved to your device when it is connected to wi-fi.
‘@kindle.com’ emails can be delivered even when you are not connected to wi-fi, but note that service fees apply.
The role of the white blood cells, which form the peripheral immune system and are crucial in inflammatory processes, has been laid aside in the context of brain structural changes in schizophrenia.
Objectives
Determine how blood cells are associated with some brain structures volumes in first episode psychosis (FEP) and their relationship with clinical variables at baseline and 1 year follow – up.
Methods
Fifty drug-naïve FEP treated between April 2013 and July 2017 at the ETEP Program at Hospital del Mar were included. Inclusion criteria were: 1) age 18-35 years; 2) fulfillment of DSM-IV-TR criteria for brief psychotic disorder, schizophreniform disorder, schizophrenia or unspecified psychosis; 3) no previous history of severe neurological medical conditions or severe traumatic brain injury; 4) presumed IQ level > 80, and 5) no substance abuse or dependence disorders except for cannabis and/or nicotine use. All patients underwent an assessment at baseline and at one-year follow-up, including sociodemographic and clinical variables (substance use, DUP, PANSS, GAF and CDSS). Fasting blood samples were obtained before administering any medication at baseline. Structural T1 MRI was performed at baseline and brain volumes were quantified though FreeSurfer software. SPSS program was used for statistical analyzes.
Results
Lymphocytes have a positive correlation with right and left hippocampus at baseline. Moreover, lymphocytes have a negative correlation with depressive symptoms at baseline and 1 year follow – up.
Conclusions
Lymphocytes may have a protective effect in some brain structures in FEP patients at baseline, especially those implicated in depressive symptoms.
To analyse the characteristics of the main leukocyte subsets and elucidate their distributions amongst the natural population. We wanted to determine whether leukocyte subsets are potential biomarkers to evaluate the risk of common chronic diseases.
Background:
The peripheral blood leukocyte count is a routine exam performed to detect pathogen infections. Recently, subsets of white blood cells and their homeostasis have shown strong associations with some chronic diseases. Therefore, studies aiming to discover whether the distribution of leukocyte counts and its subsets are useful for predicting health conditions are worthwhile.
Methods:
This cross-sectional study analysed 10 564 residents from the basic public health service project of the Health Checkup Program performed by the BaiYun Community Health Service Center. Data on demographic information, physical measurements, medical history, and routine blood examination parameters were collected using questionnaires and health check-ups. Restricted cubic spline incorporated into logistic regression analysis was performed to evaluate the association between subsets of leukocytes and common chronic diseases.
Findings:
The counts of leukocytes and their subsets in males were higher than those in females amongst all age groups, yet the percentages of lymphocytes and neutrophils did not present sex-specific differences. A low lymphocyte count and percentage were associated with old age. The neutrophil-to-lymphocyte ratio (NLR) in patients with hypertension was higher than that in the non-hypertensive population. The risk of NLR in the top quartiles was 1.17-fold higher than that in people in the lowest quartiles.
Conclusions:
The distributions of the white blood cell count and percentage were associated with age, sex, and body mass index (BMI). In addition to the immune barrier for pathogens, the NLR or monocyte-to-lymphocyte ratio (MLR) may be potentially used to indicate the risk of some chronic non-communicable diseases. Homeostasis of subsets of leukocytes may be an important biomarker for body health conditions.
Although accumulating evidence supports the hypothesis that immune/inflammatory mechanisms are associated with the pathophysiology of bipolar disorder (BD), data about the profile of chemokines (chemotactic cytokines) and chemokine receptors are still scarce. The current study was designed to evaluate the expression of chemokine receptors on lymphocytes of patients with BD in comparison with controls.
Methods:
Thirty-three patients with type I BD (N = 21 in euthymia; N = 6 in mania/hypomania; N = 6 in depression) and 22 age- and sex-matched controls were subjected to clinical evaluation and peripheral blood draw. The expression of chemokine receptors CCR3, CCR5, CXCR4, and CXCR3 on CD4+ and CD8+ lymphocytes was assessed by flow cytometry.
Results:
Patients with BD had decreased percentage of CD4+CXCR3+ (p = 0.024), CD4+CCR3+ (p = 0.042), and CD4+CCR5+ (0.013) lymphocytes in comparison with controls. The percentage of both CD4+ and CD8+ lymphocytes expressing the chemokine receptor CXCR4 was similar in patients with BD and controls. Likewise, the percentages of CD8+CXCR3+, CD8+CCR3+, and CD8+CCR5+ lymphocytes were similar in patients with BD and controls.
Conclusion:
Our findings reinforce the hypothesis that immune pathways, especially involving CD4+ lymphocytes, are involved in the physiopathology of BD.
Humans can obtain pre-formed long-chain PUFA from the diet and are also able to convert essential fatty acids (EFA) to longer-chain PUFA. The metabolic pathway responsible for EFA interconversion involves alternating desaturation and carbon chain elongation reactions, and carbon chain shortening by peroxisomal β-oxidation. Studies using stable isotope tracers or diets supplemented with EFA show that capacity for PUFA synthesis is limited in humans, such that DHA (22 : 6n-3) synthesis in men is negligible. PUFA synthesis is higher in women of reproductive age compared with men. However, the magnitude of the contribution of hepatic PUFA synthesis to whole-body PUFA status remains unclear. A number of extra-hepatic tissues have been shown to synthesise PUFA or to express genes for enzymes involved in this pathway. The precise function of extra-hepatic PUFA synthesis is largely unknown, although in T lymphocytes PUFA synthesis is involved in the regulation of cell activation and proliferation. Local PUFA synthesis may also be important for spermatogenesis and fertility. One possible role of extra-hepatic PUFA synthesis is that it may provide PUFA in a timely manner to facilitate specific cell functions. If so, this may suggest novel insights into the effect of dietary PUFA and/or polymorphisms in genes involved in PUFA synthesis on health and tissue function.
The aim of this retrospective study was to investigate the prognostic significance of pre-treatment immunological and nutritional statuses in patients with locally advanced gastric cancer (GC), and to use the risk factors to develop a predictive score. A total of 731 patients who underwent gastrectomy for stage II/III GC from November 2010 to December 2015 were recruited into this retrospective study. On the basis of univariate and further multivariate Cox regression analyses, decreased pretreatment lymphocyte count (<1·5×109/litre) and prealbumin concentrations (<180 mg/l) were identified to be independently associated with poorer overall survival (OS) and disease-free survival (DFS). Low albumin concentrations (<33 g/l) were identified as an independent risk factor only for OS, but not for DFS. Thereafter, patients who had a decreased prealbumin concentration and lymphocyte count were given a combination of serum prealbumin concentration and lymphocyte count (Co-PaL) score of 2. Patients with only one or neither of these concentrations were given a Co-PaL score of 1 or 0, respectively. Both the OS and the DFS time were inversely related to the Co-PaL scores, and the differences among the three groups were all significant. In contrast, the prognosis did not differ significantly between patients with good nutrition and those with mild to moderate malnutrition according to the prognostic nutritional index. This study indicated that the simple scoring system could accurately predict the prognosis of patients who underwent gastrectomy for stage II/III GC. The score might be helpful in terms of clinical preoperative decision-making.
Epidemiological studies have established an association between obesity, insulin resistance, type 2 diabetes and a number of cancer types. Research has focused predominantly on altered endocrine factors, growth factors and signalling pathways, with little known in man about the immune involvement in the relevant pathophysiological processes. Moreover, in an era of exciting new breakthroughs in cancer immunotherapy, there is also a need to study the safety and efficacy of immunotherapeutics in the complex setting of inflammatory-driven obesity-associated cancer. This review addresses key immune cell subsets underpinning obesity-associated inflammation and describes how such immune compartments might be targeted to prevent and treat obesity-associated cancer. We propose that the modulation, metabolism, migration and abundance of pro- and anti-inflammatory cells and tumour-specific T cells might be therapeutically altered to both restore immune balance, alleviating pathological inflammation, and to improve anti-tumour immune responses in obesity-associated cancer.
To investigate the neutrophil-to-lymphocyte ratio and sleep apnoea severity relationship.
Methods:
Patients (n = 178) were assigned to five groups according to apnoea–hypopnea indices and continuous positive airway pressure use. White blood cell, neutrophil, lymphocyte and neutrophil-to-lymphocyte ratio values were compared for each group.
Results:
The neutrophil-to-lymphocyte ratio values of severe obstructive sleep apnoea syndrome patients (group 4) were significantly higher than those of: control patients (group 1), mild obstructive sleep apnoea syndrome patients (group 2) and patients treated with continuous positive airway pressure (group 5) (p = 0.008, p = 0.008 and p = 0.003). Minimum oxygen saturation values of group 4 were significantly lower than those of groups 1, 2 and 5 (p = 0.0005, p = 0.011 and p = 0.001). There was a positive correlation between apnoea–hypopnea index and neutrophil-to-lymphocyte ratio (r = 0.758, p = 0.034), and a negative correlation between apnoea–hypopnea index and minimum oxygen saturation (r = −0.179, p = 0.012).
Conclusion:
Neutrophil-to-lymphocyte ratio may be used to determine disease severity, complementing polysomnography.
Adenoidectomy and tonsillectomy are the oldest surgical procedures. The neutrophil-to-lymphocyte ratio is an inflammatory marker. This study aimed to investigate neutrophil-to-lymphocyte ratios in chronic tonsillitis patients and to determine whether this ratio reflects the pre- and post-operative inflammatory status in these patients.
Methods:
Patients and healthy individuals were assigned to four groups: the adenoid hypertrophy, adenotonsillar hypertrophy, chronic tonsillitis and control groups. The neutrophil-to-lymphocyte ratio was calculated for each patient before surgery and one month post-surgery. Pre- and post-operative white blood cell, neutrophil and lymphocyte counts and neutrophil-to-lymphocyte ratios were compared both within and between groups.
Results:
Pre- and post-operative neutrophil-to-lymphocyte ratios were significantly higher in the chronic tonsillitis group than in the adenoid hypertrophy and adenotonsillar hypertrophy groups (p < 0.01 and p < 0.05, respectively). In the chronic tonsillitis group, post-operative neutrophil-to-lymphocyte ratios were significantly lower than pre-operative ratios (p = 0.045). The pre-operative neutrophil-to-lymphocyte ratio was significantly higher in the chronic tonsillitis group than in the adenoid hypertrophy, adenotonsillar hypertrophy and control groups (p = 0.000). In contrast, there was no significant difference in post-operative neutrophil-to-lymphocyte ratios among all groups (p = 0.584).
Conclusion:
The neutrophil-to-lymphocyte ratio measurement can be used in chronic tonsillitis patients as an effective auxiliary method for determining the necessity and timing of tonsillectomy and post-operative follow up, thereby helping prevent complications due to delayed or inadequate treatment.
The interaction between immune cells, neurotransmitters and the neuroendocrinological systems plays a role in affective disorders, especially depression. Although panic disorder (PD) shares a lot of features with depression, it is clearly a distinct disorder. Reports on immunological parameters in PD don't provide a clear picture of the immunological status of PD patients. This can partly be attributed to methodological differences between studies and small patient groups.
Objective:
The present study aims to assemble all studies on immunological parameters in PD in order to combine all available data to gain a broader perspective on this matter.
Method:
PubMed was searched for studies describing immunological parameters in PD patients without comorbid disorders or medication use. All studies had to include a healthy control group and the outcome measures had to be shared by at least one other study.
Results:
Fourteen articles were found. Although the T-lymphocytic branch and the innate immune system were normal, the B-lymphocytic branch showed some differences between PD patients and healthy controls. B-cell counts were increased in PD patients, which was underlined by increased human leucocyte antigen (HLA)-DR counts and increased immunoglobulin A levels. However, B-cell activity following mitogen stimulation was normal.
Conclusions:
PD patients show increased B-cell numbers. The finding that B-cell activity is not increased can possibly be attributed to functional exhaustion of these cells. The meaning of this finding remains unclear, although it may be potentially important in affective disorders as the same has been found in depression.
Previously, we showed that mice fed white button mushrooms (WBM) had enhanced immune functions known to help the body's antiviral defence. In the present study, we tested whether WBM conferred protection against viral infection. Young (4-month-old) and old (22-month-old) C57BL/6 mice were fed a diet containing 0, 2 or 10 % WBM powder for 8 weeks. Mice were then infected with influenza Puerto Rico/8/34 (H1N1), and killed at day 0 (uninfected), 2, 5 or 7 post-infection. The primary outcomes of the study were viral titre and body weight. Secondary outcomes were natural killer (NK) cell activity, lymphocyte proliferation and cytokine production. The results showed that WBM did not affect viral titre, nor did it prevent infection-induced weight loss. WBM supplementation was found to enhance NK cell activity in old mice and to increase interferon (IFN)-γ production in young and old mice under naive (uninfected) conditions, but it had no such effect after infection. The lack of a mushroom supplementation effect on NK activity and concanavalin A-stimulated IFN-γ production after infection may explain the immune system's failure to reduce viral load and weight loss in mice after influenza infection. WBM supplementation, however, did induce changes in other aspects of the immune response: it significantly increased the production of T-helper type 2 cytokines IL-4 and IL-10 in uninfected mice and pro-inflammatory cytokines IL-1β and TNF-α in infected mice. These mushroom-induced systemic changes, however, were not adequate to confer a protective effect against influenza infection.
Fenugreek seed has been shown to affect the intestinal microbiota and immunological responses in animals. A feeding trial with male castrated piglets was performed over 28 d without or with the addition of 1·5 g fenugreek seeds/kg complete diet in ten and eleven piglets, weaned at 21 d. In the intestinal tract, pH, lactate and SCFA were measured as major bacterial metabolites. Immune cell phenotypes, phagocytic activity and lymphocyte proliferation after stimulation with pokeweed mitogen, concanavalin A and phytohaemagglutinin M were measured by flow cytometry. Health status and performance of the piglets were not affected by fenugreek. The pH in the caecum and colon were reduced compared with the control (P< 0·05). Higher concentrations of l-lactic acid were recorded in the small-intestinal digesta (average concentrations from the duodenum, jejunum and ileum; P< 0·05), while the concentrations of SCFA remained unchanged except an increase in n-butyric acid in colon contents (P< 0·05). The piglets fed the fenugreek diet had higher Lactobacillus and clostridium cluster I concentrations and lower Escherichia, Hafnia and Shigella concentrations in the small intestine. The addition of fenugreek increased the relative concentration of the γδ T-cell population (TCR1+CD8α−) in the blood with a simultaneous reduction of antigen-presenting cells (MHCII+CD5−) (P< 0·05). Proliferation rate and phagocytosis activity of monocytes were not affected by the additive. In conclusion, fenugreek seeds might be interesting as a feed ingredient for young piglets due to their effects on the intestinal microbiota and immunological variables. The impact on performance and animal health has to be further evaluated.
The genetic and environmental determinants of variation in blood cell size and number were investigated in 392 pairs of 12-year-old twins. The following blood cell indices were measured: haemoglobin, red blood cell count, haematocrit, mean corpuscular volume, platelet number, total white cell count, level of neutrophils, monocytes, eosinophils, total lymphocytes, CD3+ lymphocytes, CD4+ lymphocytes, CD8+ lymphocytes, CD19+ lymphocytes, CD56+ lymphocytes and CD4+ /CD8+ ratio. Genetic factors contributed significantly to all blood cell measures accounting for between 61 and 96% of variance. Heritability estimates did not differ significantly between males and females, although the sample size of the present study was not large enough to exclude the possibility of sex-limited gene expression. Common environmental factors were important in determining red blood cell count and haematocrit, but were not important in determining basal levels of any white blood cell type.
There is considerable interest in the strain specificity of immune modulation by probiotics. The present study compared the immunomodulatory properties of six probiotic strains of different species and two genera in a human peripheral blood mononuclear cell (PBMC) model in vitro. Live cells of lactobacilli (Lactobacillus casei Shirota, L. rhamnosus GG, L. plantarum NCIMB 8826 and L. reuteri NCIMB 11951) and bifidobacteria (Bifidobacterium longum SP 07/3 and B. bifidum MF 20/5) were individually incubated with PBMC from seven healthy subjects for 24 h. Probiotic strains increased the proportion of CD69+ on lymphocytes, T cells, T cell subsets and natural killer (NK) cells, and increased the proportion of CD25+, mainly on lymphocytes and NK cells. The effects on activation marker expression did not appear to be strain specific. NK cell activity was significantly increased by all six strains, without any significant difference between strains. Probiotic strains increased production of IL-1β, IL-6, IL-10, TNF-α, granulocyte-macrophage colony-stimulating factor and macrophage inflammatory protein 1α to different extents, but had no effect on the production of IL-2, IL-4, IL-5 or TNF-β. The cytokines that showed strain-specific modulation included IL-10, interferon-γ, TNF-α, IL-12p70, IL-6 and monocyte chemotactic protein-1. The Lactobacillus strains tended to promote T helper 1 cytokines, whereas bifidobacterial strains tended to produce a more anti-inflammatory profile. The results suggest that there was limited evidence of strain-specific effects of probiotics with respect to T cell and NK cell activation or NK cell activity, whereas production of some cytokines was differentially influenced by probiotic strains.
This chapter reviews the mechanisms for both inflammatory and non-inflammatory mediated neural degeneration in multiple sclerosis (MS) and discusses potential therapeutic targets for neuroprotection. The classical pathological description of the MS lesion has focused on the perivenular inflammatory infiltrate characterized predominantly by lymphocytes and monocytes. Progressive axonal loss occurs in the central nervous system (CNS) of patients with MS, and the extent of this axonal loss correlates with the degree of permanent neurological deficit. Careful consideration to the pathophysiology of MS is necessary to identify candidate drugs for therapeutic trials. Stem cells may serve to enhance the function of host tissues, to provide missing chemicals or enzymes or to halt a degenerative or neoplastic process. As the currently available immunomodulatory treatments for MS have only a modest impact on progressive axonal loss and disability, there exists a pressing need to develop strategies to prevent this axonal loss.
The objective of the present study was to compare the acute effect of meals of different composition on the expression of adhesion molecules that play a key role in leucocyte trafficking. A total of twenty apparently healthy subjects randomly consumed three isoenergetic meals 1 week apart: enriched in carbohydrates (CHO), enriched in monounsaturated fat and enriched in saturated fat. Blood samples were obtained before the meals and at 2, 4, 6, 8 and 10 h after meal ingestion. Samples were analysed for LDL resistance to Cu-mediated oxidation and for the surface expression on peripheral blood mononuclear cells (PBMC) of CD62L, CD162, CD11a, CD11b, CD49d and CD54 by flow cytometry. The present results showed that there were no changes in LDL susceptibility to oxidation within and among the meals. After the CHO-enriched meal, there was a time-dependent increased expression of CD162, CD49d, CD11a and CD54 on PBMC that returned to basal values after 8–10 h. These changes were significantly greater than the ones observed after the consumption of the monounsaturated fat- and the saturated fat-enriched meals and were more evident in lymphocytes than in monocytes. In conclusion, acute ingestion of a CHO-enriched meal induces higher increases of lymphocyte activation markers than fat-enriched meals. These results suggest that long-term consumption of CHO-enriched diets may be associated with a sustained pro-inflammatory state.
Sporozoite invasion of bovine lymphocytes by Theileria parva is a pH-dependent process that occurs without the need for de novo protein synthesis. The process was inhibited by RGD(S) peptides, fibronectin and, in the presence of serum, by antibodies reactive with fibronectin. Invasion was also blocked by a range of sulphated glycoconjugates, but treatment of lymphocytes with heparitinase did not inhibit entry. Enzymic modifications of the lymphocyte surface demonstrated that trypsin-insensitive glycoproteins containing O- and N-linked carbohydrates as well as phospholipase-sensitive molecules on the host cell surface were critical to sporozoite entry. Modification of the lymphocyte surface with NEM and DTT had only marginal effects on sporozoite binding but blocked parasite internalization. Invasion was also blocked by several antibodies which cross-reacted with sporozoite surface molecules. While only a few experimental conditions specifically blocked sporozoite binding, a wider range of reagents and treatments inhibited parasite entry. The reasons for this are discussed in terms of the nature of the zippering process that facilitates sporozoite internalization.
This chapter deals with isolated angiitis of the central nervous system (CNS), and begins with an overview of the pathology and pathogenesis of the condition. The nonspecific pathological pattern of isolated CNS angiitis is characterized by infiltrations of the vascular walls with mononuclear cells including lymphocytes, macrophages, and histiocytes. The pathogenesis of isolated CNS angiitis is unknown and progress is slow because of the rarity of tissue samples acquired from carefully documented cases. Brain imaging, angiography, and brain biopsy are the diagnostic options investigated in the chapter. In patients with a unique focal presentation such as stroke, and with isolated CNS angiitis suspected on the basis of angiography alone, a course of several-weeks of high-dose corticosteroids associated with a calcium channel blocker and no immunosuppressor can be proposed. The diagnosis of reversible cerebral angiopathy should be carefully considered in these patients.
Magnesium (Mg) is the fourth most abundant mineral in the body and the most abundant intracellular divalent cation, with essential roles in many physiological functions. Consequently, the assessment of Mg status is important for the study of diseases associated with chronic deficiency. In spite of intense research activities there is still no simple, rapid, and accurate laboratory test to determine total body Mg status in humans. However, serum Mg < 0·75 mmol/l is a useful measurement for severe deficiency, and for values between 0·75 and 0·85 mmol/l a loading test can identify deficient subjects. The loading test seems to be the gold standard for Mg status, but is unsuitable in patients with disturbed kidney and intestinal functions when administered orally. There is also a need to reach a consensus on a standardized protocol in order to compare results obtained in different clinical units. Other cellular Mg measurements, such as total or ionized Mg, frequently disagree and more research and systematic evaluations are needed. Muscle Mg appears to be a good marker, but biopsies limit its usefulness, as is the case with bone Mg, the most important but heterogeneous Mg compartment. The development of new and non invasive techniques such as nuclear magnetic resonance (NMR) may provide valuable tools for routinely analysing ionized Mg in tissues. With the development of molecular genetics techniques, the recent discovery of Transient Receptor Potential Melastatin channels offers new possibilities for the sensitive and rapid evaluation of Mg status in humans.
Analysis of global gene expression in immune cells has provided unique insights into immune system function and response to infection. Recently, we applied microarray and serial analysis of gene expression (SAGE) techniques to the study of γδ T-cell function in humans and cattle. The intent of this review is to summarize the knowledge gained since our original comprehensive studies of bovine γδ T-cell subsets. More recently, we have characterized the effects of mucosal infection or treatment with microbial products or mitogens on gene expression patterns in sorted γδ and αβ T-cells. These studies provided new insights into the function of bovine γδ T-cells and led to a model in which response to pathogen-associated molecular patterns (PAMPs) induces ‘priming’ of γδ T-cells, resulting in more robust responses to downstream cytokine and/or antigen signals. PAMP primed γδ T-cells are defined by up-regulation of a select number of cytokines, including MIP1α and MIP1β, and by antigens such as surface IL2 receptor α (IL-2Rα) and CD69, in the absence of a prototypic marker for an activated γδ T-cell, IFN-γ. Furthermore, PAMP primed γδ T-cells are more capable of proliferation in response to IL-2 or IL-15 in the absence of antigen. PAMPs such as endotoxin, peptidoglycan and β-glucan are effective γδ T-cell priming agents, but the most potent antigen-independent priming agonists defined to date are condensed oligomeric tannins produced by some plants.
To determine the effect of feeding formula containing long-chain PUFA (LCP) on immune function, healthy term infants were randomised at age 2 weeks to either a standard term formula (Formula; n 14) or the same formula supplemented with the LCP 20 : 4n-6 and 22 : 6n-3 (Formula+LCP; n 16). Peripheral blood was collected at 2 and 6 weeks to measure immune cell response (the rate of [3H]thymidine uptake and cytokine production after stimulation with phytohaemagglutinin (PHA)). Compared with cells from infants receiving only human milk (HM), the rate of [3H]thymidine uptake in response to PHA, but not IL-2 production, was lower for Formula+LCP infants (P < 0·05). Compared with HM-fed infants, Formula-fed infants (but not Formula+LCP infants) produced more TNF-α (unstimulated) and had a fewer CD3+CD44+ cells before stimulation and fewer CD11c+ cells post-stimulation (P < 0·05). However, compared with Formula-fed infants, the Formula+LCP infants had an immune cell distribution (higher percentage CD3+CD44+ and CD4+CD28+ cells) and cytokine profile (lower production of TNF-α post-stimulation) that did not differ from HM infants. Additionally, it was found that feeding infants formula during the first 10 d of life influenced immune function. These infants had a higher percentage of CD3+, CD4+CD28+, and lower percentage of CD14+ cells and produced more TNF-α and interferon-γ after PHA stimulation than HM-fed infants (P < 0·05). These results demonstrate that early diet influences both the presence of specific cell types and function of infant blood immune cells. Since many diseases have a strong immunological component, these immune changes may be of physiological importance to the developing infant.