Expression of mycobacterium tuberculosis induced SOCS3 and STAT3 and the implications on innate immunity in TB patients vs healthy contacts in high TB/HIV endemic setting: A cross-sectional analytical study

Background

Mycobacterium tuberculosis (TB) remains a disease of global health concern and a leading cause of mortality arising from an infectious agent. Protective immunity to TB remains unclear. Suppressor of cytokine signaling-3 (SOCS3) and signal transduction and activator of transcription-3 (STAT3) genes have shown potential to influence innate immunity. We, therefore, explored the expression of SOCS3 and STAT3 and their implications on the innate immunity in TB patients and their healthy close contacts.

Methods

We recruited 72 TB patients and 62 healthy contacts from a high TB and HIV endemic setting (Lusaka, Zambia). We used RT-PCRT and flow cytometry to quantify the expression of SOCS, STAT3 and cytokines respectively. Data was analysed Stata version 14.0 and figures were developed in GraphPad prism version 9.1.0 (221). Assessment for associations for categorical and continuous variables was analysed using the Chi-square test and Mann-Whitney test respectively. Spearman’s rank correlation was used to evaluate the relationship between SOCS3 and IL-6. A p-value < 0.05 was considered statistically significant.

Results

Healthy contacts markedly expressed SOCS3 in both unstimulated and stimulated whole blood in comparison to TB patients (p <0.0001). STAT3 was elevated in TB patients in TB patients in stimulated blood only. IL-6 (P = < 0.0001) and IL-10 (P = <0.0001), were significantly expressed in Healthy contacts in comparison to TB patients. TNF-α (p = 0.044) were markedly elevated in TB patients in comparison to healthy contacts. IL-6 and SOCS3 correlated significantly in healthy contacts only (r = 0.429, p = 0.02).

Conclusions

Both SOCS3 and STAT3 are genes of importance in mounting protective innate immunity against TB. We propose that SOCS3 stimulation and inhibition of STAT3 as possible approaches in gene therapy and vaccine development for TB.

Immune correlates of Mycobacterium Tuberculosis patients in Zambia stratified by HIV serostatus and level of immunity-a cross-sectional analytical laboratory based study

BACKGROUND

People living with HIV (PLHIV) co-infected with tuberculosis (TB) have a distinct clinical presentation and poorer treatment outcomes compared to HIV-seronegative TB patients. Excluding low CD4 count, innate immune factors associated with TB are not fully elucidated. We, therefore, characterised and compared the expression of IL-6, TNF-α, IFN-γ, and IL-10 in whole blood of treatment naïve TB patients stimulated with heat-killed Mycobacterium tuberculosis stratified by HIV status and the level of CD4 count.

RESULTS

We recruited 39 HIV seropositive and 31 HIV seronegative TB patients. Median (IQR) age was 35(28-42) years and 31(25-36) years respectively, and a majority had pulmonary tuberculosis i.e. 38(95%) and 30(97%), respectively. The two groups were significantly different in the distribution of CD4 count, 563 [465-702.5 cells/mm3] vs 345 [157-483 cell/mm3] in HIV negative vs HIV positive respectively p = <0.001. Post stimulation, the expression of IL-6 in HIV negative TB patients was significantly higher than in the HIV positive 16,757366 [8,827-23,686 pg/ml] vs. 9,508 [5,514-15,008 pg/ml], respectively; p = 0.0360. TNF-α and IFN-γ were highly expressed in HIV negative TB patients compared to the HIV positive though not statistically significant. We only observed higher expression of IL-6 in HIV negative patients in comparison to the HIV positive when stratified by level of CD4 counts as < 500 and ≥ 500 cell/mm3 for both cohorts. 21,953 [8,990-24,206 pg/ml] vs 9,505 [5,400-15,313 pg/ml], p value = 0.0585 in patients with CD4 count < 500 cell/mm3 and 13,168 [7,087-22,584 pg/ml] vs 10,413 [7,397-14,806 pg/ml], p value = 0.3744 for patients with CD4 count of ≥ 500 cell/mm3 respectively. We found a positive pairwise correlation between TNF-α -alpha and IL-6 in both HIV positive and HIV negative patients, r = 0.61 (95% CI 0.36-0.72; p < 0.0001) and r = 0.48 (95% CI 0.15-0.68; p = 0.005) respectively. The IFNγ/IL-10 ratio was higher in HIV negative when compared to HIV positive individuals, 0.052 [0.0-0.28] vs 0.007 [0-0.32] respectively; p = 0.05759. IL-6 independently reduced the probability of TB/HIV, Adjusted odds ratio 0.99, p value 0.007.

CONCLUSIONS

This study suggests that HIV seronegative TB patients have a higher pro-inflammatory response to MTB than HIV seropositive TB patients. Further, it also shows that the level of CD4 influences immunomodulation. The findings suggest that the difference in cytokine expression may be responsible for the distinct patterns of TB presentation between HIV positive and HIV negative patient.

A comparison of vitamin D and cathelicidin (LL-37) levels between patients with active TB and their healthy contacts in a high HIV prevalence setting: a prospective descriptive study

BACKGROUND

Studies from Asia and Europe indicate an association between vitamin D deficiency and susceptibility to TB. We performed an observational case-control study to determine vitamin D and cathelicidin (LL-37) levels and their association with active TB in newly diagnosed and microbiologically confirmed adult TB patients in Zambia, a high HIV prevalence setting.

METHODS

Both total vitamin D and LL-37 were measured using ELISA from serum and supernatant isolated from cultured whole blood that was stimulated with heat-killed Mycobacterium tuberculosis. Statistical analysis was performed using STATA statistical software version 12.

RESULTS

The median vitamin D in TB patients and healthy contacts was 28.7 (19.88-38.64) and 40.8 (31.2-49.44) ng/ml, respectively (p<0.001). The median LL-37 in TB patients compared with healthy contacts was 1.87 (2.74-8.93) and 6.73 (5.6-9.58) ng/ml, respectively (p=0.0149). Vitamin D correlation with LL-37 in healthy contacts was R2=0.7 (95% CI 0.566 to 0.944), p<0.0001. Normal vitamin D significantly predicted a healthy status (OR 4.06, p=0.002).

CONCLUSIONS

Significantly lower levels of vitamin D and LL-37 are seen in adults with newly diagnosed active TB. Longitudinal studies across various geographical regions are required to accurately define the roles of vitamin D and LL-37 in preventive and TB treatment outcomes.

Impact of mHealth on contraceptive use among women and men of reproductive age in low- and middle-income countries: a systematic review and meta-analysis

OBJECTIVE

Around the world, the use of modern contraceptives has risen significantly, but the quality and reach of sexual and reproductive health services remains weak in the poorest countries. To address the high unmet need, an opportunity arises for mobile health technology (mHealth) to empower both clients and providers. However, evidence that mHealth is effective in increasing modern contraceptive use is limited and mixed, and we set out to assess its impact.

METHODS

A systematic literature search from seven electronic databases was conducted using key search terms. Individually randomised controlled trials that compared modern contraceptive use in women and men using phone message interventions and those without the intervention were included. Stata was used to calculate pooled estimates of effect under the random-effects model, as well as produce the risk of bias using the Egger's regression method. GRADEpro GDT was used to assess the quality of individual studies.

RESULTS

A pooled estimate of all of the studies showed a positive association between phone messages and contraception use, but no clear evidence of benefit (OR 1.12; 95% CI 0.97-1.29). Notably, pooled results of studies that reported modern contraceptive use as the primary outcome showed that mobile phone messaging was associated with an increase in the use of modern contraception (OR 1.22; 95% CI 1.01-1.47).

CONCLUSIONS

The finding of this systematic review suggests that mobile phone message interventions utilising a behavioural change technique are an effective method of increasing modern contraceptive use among men and women of reproductive age in low- and middle-income countries though the effect is small.

Design and Development Process of a Youth Depression Screening m-Health Application for Primary Health Care Workers in South Africa and Zambia: An Overview of the MEGA Project

Literature indicates a high prevalence and burden of mental illness in youths world-wide, which may be even higher in low- and middle-income countries (LMIC), such as South Africa and Zambia. Additionally, there is a lack of knowledge regarding youth depression amongst many primary health care (PHC) practitioners. The principal goal of the MEGA project is to provide youth with better access to mental health services and appropriate care, by developing a mental health screening mobile application tool to be used in PHC settings in South Africa and Zambia. In this study, we will use a mixed methods multi-center study design. In phase one, we will investigate the mental health literacy of PHC practitioners to identify areas in need of development. Based on the needs identified, we will develop and test a mobile health application to screen for common youth mental health problems in phase two. In phase three, we will implement and evaluate a tiered education and training program in the use of the m-health application. In the final phase, we will evaluate the acceptability and feasibility of the m-health application in PHC centres across South Africa and Zambia. Evidence suggests that PHC practitioners should routinely consider mental illness when assessing youth. However, common psychiatric disorders remain largely undetected and untreated in PHC settings. By identifying limitations in PHC workers knowledge with regard to youth mental health, we aspire to improve the depression care provided to youth in Southern Africa and Zambia by developing and implementing a locally relevant m-health application.

Chloroquine efficacy in the treatment of uncomplicated malaria at three sentinel sites in northern Togo

In Togo, chloroquine (CQ) remains the first-line drug for the treatment of uncomplicated, Plasmodium falciparum malaria. In the absence of recent data on the level of parasite resistance to antimalarial drugs, Togo's National Malaria Control Programme (NMCP) decided to assess the current efficacy of CQ in the treatment of uncomplicated, P. falciparum malaria at three sentinel sites in the north of the country. Between the September and November of 2001, the World Health Organization's standard 14-day protocol was used to investigate 153 malarious children aged 6-59 months old (46 from Sokode, 54 from Niamtougou and 53 from Dapaong). Of the subjects from Sokode, Niamtougou and Dapaong, early treatment failure was observed in 0%, 7% and 12%, late treatment failure in 0%, 11% and 17%, and overall parasitological failure in 0%, 45% [with a 95% confidence interval (CI) of 39%-51%] and 62% (CI=54%-70%), respectively. Even within northern Togo, there is clearly considerable geographical variation in the level of resistance to CQ. Before an efficient antimalarial-drug policy can be developed, there is an urgent need to develop and use the national surveillance system further, to collect relevant data on the efficacies of CQ and other antimalarial drugs, such as amodiaquine and sulfadoxine-pyrimethamine.

Condom use and its association with HIV/sexually transmitted diseases in four urban communities of sub-Saharan Africa

OBJECTIVES

To estimate rates of condom use in four urban populations in sub-Saharan Africa and to assess their association with levels of HIV infection and other sexually transmitted diseases (STDs).

METHODS

Data were obtained from a multicentre study of factors that determine the differences in rate of spread of HIV in four African cities. Consenting participants were interviewed on sexual behaviour, and also provided blood and urine samples for testing for HIV infection and other STDs. Data on sexual behaviour included information on condom use during all reported spousal and non-spousal partnerships in the past 12 months.

RESULTS

A total of 2116 adults aged 15-49 years were interviewed in Cotonou (Benin), 2089 in Yaoundé (Cameroon), 1889 in Kisumu (Kenya) and 1730 in Ndola (Zambia). Prevalence rates of HIV infection were 3.4% in Cotonou, 5.9% in Yaoundé, 25.9% in Kisumu and 28.4% in Ndola. Reported condom use was low, with the proportions of men and women who reported frequent condom use with all non-spousal partners being 21-25%, for men and 11-24% for women. A higher level of condom use by city was not associated with lower aggregate level of HIV infection. The proportions of men reporting genital pain or discharge during the past 12 months were significantly lower among those reporting frequent condom use in all sites except Yaoundé: in Cotonou, adjusted odds ratio (OR) = 0.28, 95% confidence interval (CI) = 0.09-0.94; in Kisumu, adjusted OR = 0.34, 95% CI = 0.14-0.83; and in Ndola, adjusted OR = 0.33, 95% CI = 0.12-0.90. The same association was found for reported genital ulcers in two sites only: in Cotonou, adjusted OR = 0.14, 95% CI = 0.02-1.02; and in Kisumu, adjusted OR = 0.18, 95% CI = 0.04-0.75. There were few statistically significant associations between condom use and biological indicators of HIV infection or other STDs in any of the cities.

CONCLUSION

Similar levels of condom use were found in all four populations, and aggregate levels of condom use by city could not discriminate between cities with high and low level of HIV infection. It seems that rates of condom use may not have been high enough to have a strong impact on HIV/STD levels in the four cities. At an individual level, only a male history of reported STD symptoms was found to be consistently associated with lower rates of reported condom use.

Multicentre study on factors determining differences in rate of spread of HIV in sub-Saharan Africa: methods and prevalence of HIV infection

OBJECTIVE

The objective of this study was to explore whether the differences in rate of spread of HIV in different regions in sub-Saharan Africa could be explained by differences in sexual behaviour and/or factors influencing the probability of HIV transmission during sexual intercourse.

METHODS

A cross-sectional, population-based study was conducted in two cities with a high HIV prevalence (Kisumu in Kenya and Ndola in Zambia) and two cities with a relatively low HIV prevalence (Cotonou in Benin and Yaoundé in Cameroon). In each of these cities, approximately 1000 men and 1000 women, aged 15-49 years, were randomly selected from the general population. Consenting men and women were interviewed and were tested for HIV, syphilis, herpes simplex virus type 2 (HSV-2), gonorrhoea, chlamydial infection and trichomoniasis (the latter for women only). In addition, a survey was conducted on a random sample of 300 sex workers in each city. The research instruments, including the questionnaires and the laboratory procedures, were standardized to permit comparison of results.

RESULTS

The numbers of men interviewed were 1021 in Cotonou, 973 in Yaoundé, 829 in Kisumu, and 720 in Ndola. The corresponding figures for women were 1095, 1116, 1060 and 1130. In Yaoundé, Kisumu and Ndola, the response rates for men were lower than for women due to failure to make contact with eligible men. The proportion of eligible women who were interviewed was 86% in Yaoundé, and 89% in Kisumu and Ndola. In Yaoundé, 76% of eligible men were interviewed, along with 82% in Kisumu and 75% in Ndola. The prevalence of HIV infection in men was 3.3% in Cotonou, 4.1% in Yaoundé, 19.8% in Kisumu and 23.2% in Ndola. For women, the respective figures were 3.4, 7.8, 30.1 and 31.9%. The prevalence of HIV infection among women aged 15-19 years was 23.0% in Kisumu and 15.4% in Ndola. Among women in Kisumu who had their sexual debut 5 years before the interview, the prevalence of HIV infection was 46%; in Ndola, it was 59%. Among sex workers, the prevalence of HIV infection was 57.5% in Cotonou, 34.4% in Yaoundé, 74.7% in Kisumu and 68.7% in Ndola.

CONCLUSIONS

The HIV prevalence rates in the general population confirmed our preliminary assessment of the level of HIV infection in the four cities, which was based on estimates of HIV prevalence from sentinel surveillance among pregnant women. The very high prevalence of HIV infection among young women in Kisumu and Ndola calls for urgent intervention.

Interpreting sexual behaviour data: validity issues in the multicentre study on factors determining the differential spread of HIV in four African cities

BACKGROUND

The main conclusion of the multicentre study on factors determining the differential spread of HIV in four African cities was that differences in sexual behaviour could not, by themselves, explain the differences in HIV prevalence between the four cities. The present paper examines three potential sources of bias that could invalidate this conclusion: (1) changes in sexual behaviour since the start of the HIV epidemics; (2) bias due to the low response rates of men; and (3) bias in reported sexual behaviour.

METHODS

To assess whether there have been any changes in sexual behaviour over time, selected parameters of sexual behaviour were compared between different age groups in the four cities. The maximum likely extent of bias due to non-participation of men in Yaoundé, Kisumu and Ndola was assessed with a simulation exercise, in which records of non-participants were replaced with records of 'low activity men' in Yaoundé and 'high activity men' in Kisumu and Ndola. To assess the validity of the sexual behaviour data, internal validity checks were carried out: comparing biological data on sexually transmitted infections with reports; comparing reports of spouses; and comparing numbers of sex partners reported by men and women. A fourth method consisted of comparing the findings of the multicentre study with an external source, Demographic and Health Surveys (DHS).

RESULTS

There were differences in sexual behaviour between the younger and the older age groups in all four cities but there was no evidence of a shift towards safer sexual behaviour in the high HIV prevalence cities. After simulating results for male non-participants in Yaoundé, Kisumu and Ndola, the median lifetime number of sex partners was similar in Yaoundé, Kisumu and Ndola. By testing for various sexually transmitted infections among men and women aged 15-24 years who reported that they had never had sexual intercourse, we could establish that, in all four cities, at least 1-9% of men and 6-18% of women had misreported their sexual activity. The number of non-spousal partners in the past 12 months reported by men was two to three times higher than the number reported by women, as has been found in other studies. The most consistent differences between our survey and the DHS were found in the numbers of non-spousal partners in the past 12 months reported by never-married men and women. In all four cities, participants reported more non-spousal partners in the DHS than in our survey.

CONCLUSIONS

In all four cities, we found evidence that men as well as women misreported their sexual behaviour, but overall it seems that under-reporting of sexual activity was not more common or more serious in the two high HIV prevalence cities than in the two low HIV prevalence cities. We believe that the main conclusions of the multicentre study still hold.

Concurrent sexual partnerships and HIV prevalence in five urban communities of sub-Saharan Africa

OBJECTIVE

To estimate parameters of concurrent sexual partnerships in five urban populations in sub-Saharan Africa and to assess their association with levels of HIV infection and other sexually transmitted infections (STI).

METHODS

Data were obtained from a multicentre study of factors which determine the differences in rate of spread of HIV in five African cities. Consenting participants were interviewed on sexual behaviour and at four of the five sites also provided a blood and a urine sample for testing for HIV and other STI. Data on sexual behaviour included the number of partnerships in the 12 months preceding the interview as well as the dates of the start and end of each partnership. Summary indices of concurrent sexual partnerships -- some of which were taken from the literature, while others were newly developed -- were computed for each city and compared to HIV and STI prevalence rates.

RESULTS

A total of 1819 adults aged 15--49 years were interviewed in Dakar (Senegal), 2116 in Cotonou (Benin), 2089 in Yaoundé (Cameroon), 1889 in Kisumu (Kenya) and 1730 in Ndola (Zambia). Prevalence rates of HIV infection were 3.4% for Cotonou, 5.9% for Yaoundé, 25.9% for Kisumu and 28.4% for Ndola, and around 1% for Dakar. The estimated fraction of sexual partnerships that were concurrent at the time of interview (index k) was relatively high in Yaoundé (0.98), intermediate in Kisumu (0.44) and Cotonou (0.33) and low in Ndola (0.26) and in Dakar (0.18). An individual indicator of concurrency (iic) was developed which depends neither on the number of partners nor on the length of the partnerships and estimates the individual propensity to keep (positive values) or to dissolve (negative values) on-going partnership before engaging in another one. This measure iic did not discriminate between cities with high HIV infection levels and cities with low HIV infection levels. In addition, iic did not differ significantly between HIV-infected and uninfected people in the four cities where data on HIV status were collected.

CONCLUSION

We could not find evidence that concurrent sexual partnerships were a major determinant of the rate of spread of HIV in five cities in sub-Saharan Africa. HIV epidemics are the result of many factors, behavioural as well as biological, of which concurrent sexual partnerships are only one.

Does the availability of blood slide microscopy for malaria at health centers improve the management of persons with fever in Zambia?

Some Ministries of Health in Africa plan to make blood slide microscopy available in peripheral health centers to improve malaria diagnosis over the current practice, which relies solely on clinical findings. To assess whether microscopy improves the management of febrile persons in health centers, we prospectively reviewed medical records of all outpatients visiting six health centers with laboratories in Zambia during a 2-3-day period. Staff interviews and a blinded review of a series of blood slides from each facility by two expert microscopists were also conducted. Of 1,442 outpatients, 655 (45%) reported fevers or had a temperature > or = 37.5 degrees C. Blood slide microscopy was ordered in 28-93% of patients with fever (mean = 46%). Eighty-eight (35%) patients without parasitemia were prescribed an antimalarial drug. Antimalarial drugs were prescribed with equal frequency to those who were referred for a blood slide (56%) and those not referred (58%). The sensitivity of microscopy was 88% and the specificity was 91%. Use of malaria microscopy varied widely, indicating that clinicians are not using standard criteria for ordering this test. Although diagnosis by microscopy was generally accurate, it appeared to have had little impact on the treatment of persons with fever. Guidelines for using blood slide microscopy are needed and prescription of antimalarial drugs should be discouraged when slide results are negative.