Vitamin A levels and immunity in humans

Cryotherapy plus low-dose oral isotretinoin vs cryotherapy only for the treatment of anogenital warts: a randomized clinical trial

BACKGROUND

Anogenital warts are a common human papillomavirus infection. They cause emotional distress, especially when they are in the anogenital region. Cryotherapy is a first-line treatment. Previous clinical trials and case series have reported variable results with retinoids (isotretinoin) as adjuvant therapy.

OBJECTIVE

To determine the safety and efficacy of low-dose oral isotretinoin as adjuvant treatment of anogenital warts.

METHODS

Forty-six patients with anogenital warts were randomly assigned to isotretinoin + cryotherapy (n = 23) or only cryotherapy (n = 23). Patients were allocated via an interactive web-based randomization system. Evaluators were blinded to treatments. Isotretinoin 20 mg/daily + cryotherapy or cryotherapy were prescribed for 6 weeks. Patients were followed for 4 months. Genotyping of lesions was performed before treatment started. Dermatology Life Quality Index (DLQI) and Columbia-Suicide Severity Rating Scale (C-SSRS) were measured at the beginning and end of therapy. All patients completed the study.

RESULTS

Both Groups had 50% clearance at the end of treatment. Recurrence in the combined group was not significantly lower than in the cryotherapy group (P = 0.59). Improvement was observed in the DLQI of all patients in both groups (P = 0.001). No suicidal intention was detected with the C-SSRS. Two patients (one in each group) had liver function test abnormalities after treatment.

CONCLUSION

Combined therapy showed a slight not significant efficacy for anogenital warts in Hispanic patients. Low-dose isotretinoin seems to be safe even when it is used with cryotherapy on anogenital warts.

TRIAL REGISTRATION

On April 25, 2019 with registration number DE19-00004, CONBIOÉTICA-19-CEI-001-20160404. Prospectively registered.

Clinical Observations, Plasma Retinol Concentrations, and In Vitro Lymphocyte Functions in Children With Sickle Cell Disease

Background

Children with sickle cell disease (SCD) often have infections, growth deficits, and impaired immunity, problems that also are observed in individuals with a vitamin A deficiency (plasma retinol concentration <20 μg/dL). The goal of this study was to investigate the association between vitamin A, health status, and the in vitro immune function of children with SCD.

Methods

Fifty-nine children (40 SS, 11 SC, and 8 Sβ^thalassemia [Sβ^thal] hemoglobin genotypes) 9 months to 18 years old were investigated for plasma levels of retinol, retinol binding protein, C-reactive protein, alpha-1-acid glycoprotein, lymphocyte proliferation, and interleukin (IL)-2 activity in supernatant of phytohemagglutinin-treated lymphocytes.

Results

The plasma retinol concentrations of children with SCD (mean 57.6 μg/dL, range 4.6-116 μg/dL) were not different from those of 21 normal individuals (mean 62 μg/dL, range 28.7-162 μg/dL). Plasma retinol concentrations did not vary by hemoglobin genotype but were lower in boys than in girls (P < 0.05) and were also lower in children with inflammation (P = 0.1). Seven children (11.9%) (6 HbSS, 1 HbSβ^0thal) were vitamin A-deficient, and 9 children (15.3%) had suboptimal vitamin A status (plasma retinol concentration of 20-29 μg/dL). Children with vitamin A deficiency had slightly lower height (P = 0.09) and weight mean percentiles, lymphocyte proliferative responses, and IL-2 activity (P > 0.1), but higher means of C-reactive protein (P = 0.05), pain crisis episodes and inflammation (P = 0.1), and health scores (P > 0.1) than children who were not vitamin A-deficient. Lymphocyte proliferative responses negatively correlated with health score, pain crisis episodes, and blood units received, but positively correlated with retinol binding protein (P < 0.05 to P = 0.1).

Conclusion

Identification and correction of suboptimal vitamin A status in children with SCD may improve immunity and attenuate certain health complications associated with this disease.

Commensals Suppress Intestinal Epithelial Cell Retinoic Acid Synthesis to Regulate Interleukin-22 Activity and Prevent Microbial Dysbiosis

Retinoic acid (RA), a vitamin A metabolite, regulates transcriptional programs that drive protective or pathogenic immune responses in the intestine, in a manner dependent on RA concentration. Vitamin A is obtained from diet and is metabolized by intestinal epithelial cells (IECs), which operate in intimate association with microbes and immune cells. Here we found that commensal bacteria belonging to class Clostridia modulate RA concentration in the gut by suppressing the expression of retinol dehydrogenase 7 (Rdh7) in IECs. Rdh7 expression and associated RA amounts were lower in the intestinal tissue of conventional mice, as compared to germ-free mice. Deletion of Rdh7 in IECs diminished RA signaling in immune cells, reduced the IL-22-dependent antimicrobial response, and enhanced resistance to colonization by Salmonella Typhimurium. Our findings define a regulatory circuit wherein bacterial regulation of IEC-intrinsic RA synthesis protects microbial communities in the gut from excessive immune activity, achieving a balance that prevents colonization by enteric pathogens.

Possible Immunomodulating Effect of Retinol on Cytokines Secretion in Patients with Recurrent Furunculosis

Recurrent furunculosis is an infection of hair follicles which results in formation of abscesses. Previous studies showed that the pathogenesis of the disease may include an immune-mediated component as the proliferative response of peripheral blood lymphocytes to staphylococcal antigen is depressed. The aim of our study was to evaluate cytokines concentration in the plasma of patients with recurrent furunculosis and to determine whether retinol affects the secretion of those cytokines in patients with recurrent furunculosis and healthy subjects. Blood samples were taken from 15 patients with recurrent furunculosis and 15 age-matched healthy subjects. A quantitative determination of selected cytokines (IL-17, 13, 2, 10, 4, IFN-γ, TNF-α) was performed in the plasma at baseline and after 72-h culture of peripheral blood mononuclear cells with and without retinol in both groups. In the plasma of patients with recurrent furunculosis, concentration of IL-10, 2, and TNF-α was significantly higher, whereas IL-13 significantly lower when compared with healthy subjects. After retinol stimulation, the concentration of IL-17 and IFN-γ increased significantly in both groups. Secretion of anti-inflammatory cytokines, especially IL-10 (p < 0.002) and 13 (p < 0.01), achieved lower levels in recurrent furunculosis samples than in those of healthy controls. Network of cytokines differs in patients with recurrent furunculosis from healthy subjects. Retinol stimulation affects secretion of both pro-inflammatory and anti-inflammatory cytokines. Further studies are recommended for better understanding the pathomechanism of recurrent furunculosis and potential clinical use of retinol in patients affected by recurrent furunculosis.

Frequency of tuberculosis among diabetic patients in the People's Republic of China

The People’s Republic of China has nearly the highest incidence of both diabetes mellitus (DM) and tuberculosis (TB) worldwide. DM increases the risk of TB by two to three times and adversely affects TB treatment outcomes. The increasing epidemic of DM in the People’s Republic of China is due to decreased physical activity, unhealthy diet, and obesity. Over the last 20 years, the excellent free China National Tuberculosis Program has been set up, and the “DOTS” (directly observed treatment + short-course chemotherapy) model for TB control has successfully reduced the burden of TB, but the disease is still a considerable problem. Given the high burden of TB and DM in the People’s Republic of China and the relationship between the two diseases, it is sensible to screen DM patients for TB. A bidirectional screening of the two diseases was conducted in the People’s Republic of China from 2011 to 2012, which identified a TB incidence in patients with DM of about 958 per 100,000. Here, we report the findings of our recent study on the incidence of TB among diabetic patients in the People’s Republic of China. The data agree with those of previous reports.

Rationale and design of a randomized controlled trial of the effect of retinol and vitamin D supplementation on treatment in active pulmonary tuberculosis patients with diabetes

Background

The association between pulmonary tuberculosis (PTB) and diabetes mellitus (DM) has been previously attracted much attention. Diabetes alters immunity to tuberculosis, leading to more frequent treatment failure in TB patients with DM. Moreover, TB and DM often coincide with micronutrients deficiencies, such as retinol and vitamin D, which are especially important to immunity of the body and may influence pancreas β-cell function. However, the effects of retinol and vitamin D supplementation in active TB patients with diabetes on treatment outcomes, immune and nutrition state are still uncertain. We are conducting a randomized controlled trial of vitamin A and/or D in active PTB patients with DM in a network of 4 TB treatment clinics to determine whether the supplementation could improve the outcome in the patients.

Methods/design

This is a 2×2 factorial trial. We plan to enroll 400 active PTB patients with DM, and randomize them to VA (2000 IU daily retinol); VD (400 IU daily cholecalciferol); VAD (2000 IU daily retinol plus 400 IU cholecalciferol) or control (placebo) group. Our primary outcome measure is the efficacy of anti-tuberculosis treatment and ameliorating of glucose metabolism, and the secondary outcome measure being immune and nutrition status of the subjects. Of the first 37 subjects enrolled: 8 have been randomized to VA, 10 to VD, 9 to VAD and 10 to control. To date, the sample is 97.3% Han Chinese and 91.9% female. The average fasting plasma glucose level is 12.19 mmol/L.

Discussion

This paper describes the design and rationale of a randomized clinical trial comparing VA and/or VD supplementation to active pulmonary TB patients with DM. Our trial will allow rigorous evaluation of the efficacy of the supplementation to active TB and DM therapy for improving clinical outcomes and immunological condition. This detailed description of trial methodology can serve as a template for the development of future treatment scheme for active TB patient with DM.

Trial registration

ChiCTR-TRC-12002546

A novel retinoic acid, catechin hydrate and mustard oil-based emulsion for enhanced cytokine and antibody responses against multiple strains of HIV-1 following mucosal and systemic vaccinations

Non-replicating protein- or DNA-based antigens generally require immune-enhancing adjuvants and delivery systems. It has been particularly difficult to raise antibodies against gp120 of HIV-1, which constitutes an important approach in HIV vaccine design. While almost all effort in adjuvant research has focused on mimicking the pathogens and the danger signals they engender in the host, relatively little effort has been spent on nutritive approaches. In this study, a new nutritive immune-enhancing delivery system (NIDS) composed of vitamin A, a polyphenol-flavonoid, catechin hydrate, and mustard oil was tested for its adjuvant effect in immune responses against the gp120 protein of HIV-1(CN54). Following a combination of two mucosal and two systemic vaccinations of mice, we found significant enhancement of both local and systemic antibodies as well as cytokine responses. These data have important implications for vaccine and adjuvant design against HIV-1 and other pathogens.

Nutritional and Pharmacological Modulation of the Metabolic Response of Severely Burned Patients: Review of the Literature (Part III)*

Severe burn patients are some of the most challenging critically ill patients, with an extreme state of physiological stress and an overwhelming systemic metabolic response. Increased energy expenditure to cope with this insult necessitates mobilization of large amounts of substrate from fat stores and active muscle for repair and fuel, leading to catabolism. The hypermetabolic response can last for as long as nine months to one year after injury and is associated with impaired wound healing, increased infection risks, erosion of lean body mass, hampered rehabilitation, and delayed reintegration of burn survivors into society.Reversal of the hypermetabolic response by manipulating the patient's physiological and biochemical environment through the administration of specific nutrients, growth factors, or other agents, often in pharmacological doses, is emerging as an essential component of the state of the art in severe burn management. Early enteral nutritional support, control of hyperglycaemia, blockade of catecholamine response, and use of anabolic steroids have all been proposed to attenuate hypermetabolism or to blunt catabolism associated with severe burn injury. The present study is a literature review of the proposed nutritional and metabolic therapeutic measures in order to determine evidence-based best practice. Unfortunately, the present state of our knowledge does not allow the formulation of clear-cut guidelines. Only general trends can be outlined which will certainly have some practical applications but above all will dictate future research in the field.

Association of vitamin A deficiency with decrease in TNF-α expressing CD3-CD56+ NK cells in Ghanaians

Although low plasma vitamin A concentrations are associated with increased incidence or severity of infections such as respiratory tract infection and measles in children, there is a paucity of data on the effect of vitamin A deficiency on the distribution of, and cytokine production by, the different cellular immune subsets in humans. We conducted a cross-sectional study in a district in Ghana to characterize cellular subsets and functional capacity of peripheral blood mononuclear cells from vitamin A deficient and vitamin A sufficient (normal) individuals, and evaluated the relationships between vitamin A concentration in plasma and cellular immune status. We measured the percentages of selected cellular phenotypes and intracellular cytokine expression and describe the differential cellular subset distributions and alterations in cytokine expression in participants with normal and deficient vitamin A concentrations. The major change observed in the constitution of cellular subsets was a decrease in TNF-α expressing CD3-CD56+ NK cells in those with vitamin A deficiency compared with normal individuals. CD4+ T cell proliferation and production of IFN-γ and IL-4 were not statistically different between the two groups. These results support previous studies that demonstrated decreased NK cell activity in vitamin A deficient animals. The decrease in TNF-α expressing NK cells observed in vitamin A deficient individuals in this study could help to explain the decreased resistance to infections observed in those with vitamin A deficiency.

A comparison of the effect of vitamin A on cytokine secretion by mononuclear cells of preterm newborns and adults

BACKGROUND

For a long time vitamin A has been known to be essential for immune defense of the organism and protection against infections. Vitamin A deficiency in children is associated with morbidity and mortality from infectious diseases which could be prevented and even alleviated by vitamin A supplementation. Moreover, this vitamin is involved in the modulation of immunological and inflammatory responses by regulation of cytokine production. The aim of the study was to compare the in vitro effect of vitamin A on the production of pro-inflammatory (IL-1beta and IL-6) and anti-inflammatory (IL-1 receptor antagonist (ra) and IL-10) cytokines, as well as IL-2 and IFNgamma by cord blood mononuclear cells (CBMC) of preterm newborns to that of peripheral blood mononuclear cells (PBMC) from adults.

METHODS

Mononuclear cells (MC) from individuals of the two age groups were incubated with vitamin A (retinyl palmitate) at various concentrations in the presence of phytohemagglutinin for IL-2 and IFNgamma production or LPS for IL-1beta, IL-1ra, IL-6 and IL-10 secretion. The level of the cytokines in the supernatants was tested by ELISA.

RESULTS

Vitamin A exerted an in vitro inhibitory effect on the production of the anti-inflammatory cytokine IL-1ra by MC of preterm newborns and adults, but did not affect the secretion of the pro-inflammatory cytokines IL-1beta, IL-6 and IFNgamma. Vitamin A caused inhibition of IL-10 secretion by cells from adults, but it did not significantly affect this function in cells from newborns except when high unphysiological doses were applied. In addition vitamin A stimulated the secretion of IL-2 by cells isolated from adults but had no effect on those derived from premature neonates.

CONCLUSIONS

The results indicate that vitamin A may affect the immune function of premature infants via inhibition of IL-1ra secretion. It is suggested that the beneficial effect of vitamin A on the clinical course of bronchopulmonary dysplasia (BPD) may be due to the reduced production of anti-inflammatory cytokines by neonatal CBMC. This may indicate the importance of the pro-inflammatory cytokines in the management of severe lung diseases and BPD.

An armamentarium of wart treatments

Patients and clinicians experience the frustration of cutaneous viral warts caused by infection with the human papilloma virus (HPV).Warts appear in various forms on different sites of the body and include common warts (verruca vulgaris), plane or flat warts, myrmecia, plantar warts, coalesced mosaic warts, filiform warts, periungual warts, anogenital warts (venereal or condyloma acuminata), oral warts and respiratory papillomas. Cervical infection with HPV is now known to cause cervical cancer if untreated. A review of the medical literature reveals a huge armamentarium of wart monotherapies and combination therapies. Official evidence-based guidelines exist for the treatment of warts, but very few of the reported treatments have been tested by rigorous blinded, randomized controlled trials.Therefore, official recommendations do not often include treatments with reportedly high success rates, but they should not be ignored when considering treatment options. It is the purpose of this review to provide a comprehensive overview of the wart treatment literature to expand awareness of the options available to practitioners faced with patients presenting with problematic warts.

Effect of vitamin A on the CD44 expression in the small intestine of rats with obstructive jaundice

HYPOTHESIS

In this study, the influence of obstructive jaundice on the CD44 expression in the rat small intestine and the alterations of this CD44 expression by vitamin A given intraperitoneally (200 IU/g/day) are evaluated.

MATERIALS AND METHODS

In a prospective animal model study, 32 Sprague-Dawley rats were randomized into four groups: group A rats (n = 8) underwent sham operation and were given daily saline intraperitoneally for 2 weeks (sham + saline); group B animals (n = 8) underwent sham operation and were given daily vitamin A intraperitoneally for 2 weeks (sham + vitamin A); group C rats (n = 8) underwent common bile duct ligation and were given daily saline intraperitoneally for 2 weeks (obstructive jaundice + saline), and group D animals (n = 8) underwent common bile duct ligation and were given daily vitamin A intraperitoneally for 2 weeks (obstructive jaundice + vitamin A). After 2 weeks, standardized jejunum and ileum segments were harvested from all animals. The expression of CD44 on the cell surface was evaluated immunohistochemically. Comparisons among the four groups were done.

RESULTS

The plasma bilirubin, aspartate transaminase, alanine transaminase, alkaline phospatase, and gamma-glutamyltransferase levels in groups C and D (obstructive jaundice groups) were higher than those in groups A and B (sham groups; p < 0.05). There was no difference between groups A and B (sham groups) with regard to the number of cells expressing surface CD44 in jejunum and ileum. When groups A and B were compared with group C (obstructive jaundice + saline) animals, the number of cells expressing surface CD44 was significantly decreased in both jejunum and ileum in group C. The difference between sham groups (A and B) and group C was found to be significant (p < 0.05). When group D (obstructive jaundice + vitamin A) was compared with group C (obstructive jaundice + saline), the number of cells expressing surface CD44 was significantly increased in jejunum and ileum in group D animals (p < 0.05), higher than in the sham groups (A and B). The difference between group D and sham groups (A and B) was found to be significant (p < 0.05).

CONCLUSION

Obstructive jaundice for 2 weeks significantly decreased the CD44 expression in the rat small intestine. We found that daily intraperitoneal administration of vitamin A in rats with obstructive jaundice for 2 weeks significantly restored the impaired CD44 expression.

Vitamin A supplementation increases ratios of proinflammatory to anti-inflammatory cytokine responses in pregnancy and lactation

Vitamin A supplementation reduces child mortality in populations at risk of vitamin A deficiency and may also reduce maternal mortality. One possible explanation for this is that vitamin A deficiency is associated with altered immune function and cytokine dysregulation. Vitamin A deficiency in pregnancy may thus compound the pregnancy-associated bias of cellular immune responses towards Th-2-like responses and exacerbate susceptibility to intracellular pathogens. We assessed mitogen and antigen-induced cytokine responses during pregnancy and lactation in Ghanaian primigravidae receiving either vitamin A supplementation or placebo. This was a double-blind, randomized, placebo-controlled trial of weekly vitamin A supplementation in pregnant and lactating women. Pregnancy compared to postpartum was associated with a suppression of cytokine responses, in particular of the proinflammatory cytokines interferon (IFN)-gamma and tumour necrosis factor (TNF)-alpha. Mitogen-induced TNF-alpha responses were associated with a decreased risk of peripheral parasitaemia during pregnancy. Furthermore, vitamin A supplementation was significantly associated with an increased ratio of mitogen-induced proinflammatory cytokine (IFN-gamma) to anti-inflammatory cytokine (IL-10) during pregnancy and in the postpartum period. The results of this study indicate that suppression of proinflammatory type 1 immune responses and hence immunity to intracellular infections, resulting from the combined effects of pregnancy and vitamin A deficiency, might be ameliorated by vitamin A supplementation.

Vitamin a deficiency in patients with common variable immunodeficiency

Vitamin A, a naturally occuring antioxidant micronutrient, has immunomodulating effect in patients with immunodeficiency, including an influence on cytokine production and lymphocyte growth and functions. Vitamin A deficiency is associated with a shift from type 2 cytokines to predominantly type 1 cytokines. The aims of this study were to determine Vitamin A status in Common variable immunodeficiency (CVID) patients and the relationship between Vitamin A status and cytokines production. Serum Vitamin A, neopterin, TNF-alpha, IL-2, IL-4, and IL-10 levels were determined in 19 CVID patients and 15 healthy children. Effects of 9-cis retinal, Vitamin A derivative, on cytokines (TNF-alpha, IL-2, IL-4 and IL-10) production in lymphocytes were tested in vitro condition using lymphocyte cultures obtained from CVID patients and healthy children.Serum Vitamin A level in CVDI patients was, 21.1+/- 1.5 microg/dL, significantly (p < 0.001) lower than the value, 35.7+/- 1.8 microg/dL, observed in healthy children. Serum neopterin level in the patients was, 9.8+/- 2.9 nmol/L, higher (p < 0.05) than the value, 3.9+/- 0.7 nmol/L, observed in control group. Common variable immunodeficiency patients, serum IL-4 level was significantly (p < 0.05) lower than the value observed for healthy children. Serum TNF-alpha, IL-2 and IL-10 levels were similar in the patients and healthy children. Vitamin A derivative, 9-cis retinal, increased TNF-alpha and IL-4 production in cultured mononuclear cells obtained from control and CVID patients. Vitamin A derivative, also, increased IL-2 and Il-4 production in cultured mononuclear cells obtained from CVID patients. These results show that CVID patients have low serum Vitamin A levels and high serum neopterin levels. A supplementation with Vitamin A may have role in downregulation of inflammatory responses in CVID patients.

Effects of vitamin a supplementation on immune responses and correlation with clinical outcomes

Vitamin A supplementation to preschool children is known to decrease the risks of mortality and morbidity from some forms of diarrhea, measles, human immunodeficiency virus (HIV) infection, and malaria. These effects are likely to be the result of the actions of vitamin A on immunity. Some of the immunomodulatory mechanisms of vitamin A have been described in clinical trials and can be correlated with clinical outcomes of supplementation. The effects on morbidity from measles are related to enhanced antibody production and lymphocyte proliferation. Benefits for severe diarrhea could be attributable to the functions of vitamin A in sustaining the integrity of mucosal epithelia in the gut, whereas positive effects among HIV-infected children could also be related to increased T-cell lymphopoiesis. There is no conclusive evidence for a direct effect of vitamin A supplementation on cytokine production or lymphocyte activation. Under certain circumstances, vitamin A supplementation to infants has the potential to improve the antibody response to some vaccines, including tetanus and diphtheria toxoids and measles. There is limited research on the effects of vitamin A supplementation to adults and the elderly on their immune function; currently available data provide no consistent evidence for beneficial effects. Additional studies with these age groups are needed.

Peripheral blood cell-specific cytokines in persons with untreated HIV infection in Malawi, Africa

Human immunodeficiency virus (HIV) infection is the primary cause of morbidity and mortality in Malawi, Africa, because of its many effects on the immune system. Immune cells communicate through cytokines; therefore, we examined the relationships between HIV serostatus and cell-specific cytokine production for 40 asymptomatic, employed adults and 312 acutely ill, hospitalized patients in Malawi. We also measured the plasma HIV-1 RNA levels of 13 asymptomatic persons and 83 patients found to be HIV(+). We incubated peripheral whole blood with brefeldin-A +/- phorbol 12-myristate 13-acetate and ionomycin and then permeabilized, fixed, fluorescently stained, and examined the mononuclear cells with four-color, six-parameter flow cytometry. The percentage of lymphocytes expressing CD4 did not differ significantly between the HIV(+) and HIV(-) healthy adults (medians, 35.2 vs. 40.8%, respectively), but a wide array of cytokine parameters were lower in the HIV(+) than in the HIV(-) asymptomatic persons, for example, median percentages of T cells producing induced interleukin 2 (IL-2) (8.7 vs. 16.5%, respectively) and spontaneously producing IL-6 (0.7 vs. 11.0%, respectively). Also, four T cell parameters reflecting type 2-to-type 1 cytokine balances (T2/T1) were higher in the HIV(+), versus HIV(-), asymptomatic persons. Unlike the healthy adults, for patients with mycobacteremia/fungemia or malaria, the HIV(+) patients had higher median percentages of T cells and CD8(+) T cells producing induced interferon gamma than did the HIV(-) PATIENTS: For both asymptomatic and acutely ill persons, HIV-1 plasma levels were positively correlated with T2/T1 parameters. Cell-specific cytokine effects of HIV infection may precede measurable effects on CD4 expression. Cytokine therapies, even beyond periodic administration of IL-2, may improve the responses of HIV-infected persons to both HIV and coinfections.

Spontaneous cytokine production and its effect on induced production

Cytokines regulate cellular immune activity and are produced by a variety of cells, especially lymphocytes, monocytes, and macrophages. Multiparameter flow cytometry is often used to examine cell-specific cytokine production after in vitro phorbol 12-myristate 13-acetate and ionomycin induction, with brefeldin A or other agents added to inhibit protein secretion. Spontaneous ex vivo production reportedly rarely occurs. We examined the spontaneous production of interleukin 2 (IL-2), IL-4, IL-6, IL-8, IL-10, tumor necrosis factor alpha (TNF-alpha), and gamma interferon (IFN-gamma) by peripheral-blood B lymphocytes, T cells, CD8(-) T cells, CD8(+) T cells, CD3(-) CD16/56(+) lymphocytes (natural killer [NK] cells), CD3(+) CD16/56(+) lymphocytes (natural T [NT] cells), and/or monocytes of 316 acutely ill hospitalized persons and 62 healthy adults in Malawi, Africa. We also evaluated the relationship between spontaneous and induced cytokine production. In patients, spontaneous TNF-alpha production occurred most frequently, followed in descending order by IFN-gamma, IL-8, IL-4, IL-10, IL-6, and IL-2. Various cells of 60 patients spontaneously produced TNF-alpha; for 12 of these patients, TNF-alpha was the only cytokine produced spontaneously. Spontaneous cytokine production was most frequent in the immunoregulatory cells, NK and NT. For IL-2, IL-4, IL-6, IL-8, and IL-10, spontaneous cytokine production was associated with greater induced production. For TNF-alpha and IFN-gamma, the relationships varied by cell type. For healthy adults, IL-6 was the cytokine most often produced spontaneously. Spontaneous cytokine production was not unusual in these acutely ill and healthy persons living in an area where human immunodeficiency virus, mycobacterial, malaria, and assorted parasitic infections are endemic. In such populations, spontaneous, as well as induced, cell-specific cytokine production should be measured and evaluated in relation to various disease states.